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Evidence for Osmotic Regulation of Hydrolytic Enzyme Production in Germinating Barley Seeds 1
PubMed Central
?-Amylase levels in intact seeds of barley (Hordeum vulgare L. cv. Himalaya) reach a maximum at 3 to 4 days of germination while gibberellin levels continue to increase beyond 6 days of germination. In contrast to its effect on half seeds, gibberellic acid does not increase the total amount of ?-amylase produced in germinating seeds. The inability of gibberellic acid to stimulate ?-amylase production is not related to its availability; rather, evidence suggests that a factor(s) in whole seeds prevents further enhancement of ?-amylase formation and accumulation. Hydrolysis products accumulate in the subaleurone space of the endosperm of germinating seeds up to concentrations of 570 milliosmolar. Chromatography of these hydrolysis products indicate the presence of maltose and glucose. Calculations based on reducing sugar determinations show that glucose accounts for as much as 57% of the solutes present in the endosperm fluid. Both maltose and glucose in the range of 0.2 to 0.4 M effectively inhibit the production of ?-amylase by isolated barley aleurone layers. This inhibition is quantitatively similar to that brought about by solutions of polyethylene glycol and mannitol. On the basis of these data we propose that hydrolysis products which accumulate in the starchy endosperm of germinating seeds function to regulate the production of hydrolytic enzymes by the aleurone layer. Images
Jones, R. L.; Armstrong, J. E.
Response to temperature stress of reactive oxygen species scavenging enzymes in the cross-tolerance of barley seed germination*
A number of studies have shown the existence of cross-tolerance in plants, but the physiological mechanism is poorly understood. In this study, we used the germination of barley seeds as a system to investigate the cross-tolerance of low-temperature pretreatment to high-temperature stress and the possible involvement of reactive oxygen species (ROS) scavenging enzymes in the cross-tolerance. After pretreatment at 0 °C for different periods of time, barley seeds were germinated at 35 °C, and the content of malondialdehyde (MDA) and the activities of ROS scavenging enzymes were measured by a spectrophotometer analysis. The results showed that barley seed germinated very poorly at 35 °C, and this inhibitive effect could be overcome by pretreatment at 0 °C. The MDA content varied, depending on the temperature at which seeds germinated, while barley seeds pretreated at 0 °C did not change the MDA content. Compared with seeds germinated directly at 35 °C, the seeds pretreated first at 0 °C and then germinated at 35 °C had markedly increased activities of superoxide dismutase (SOD), ascorbate peroxidase (APX), catalase (CAT), and glutathione reductase (GR). The SOD and APX activities of seeds germinated at 35 °C after 0 °C-pretreatment were even substantially higher than those at 25 °C, and GR activity was similar to that at 25 °C, at which the highest germination performance of barley seeds was achieved. These results indicate that low-temperature pretreatment can markedly increase the tolerance of barley seed to high temperature during germination, this being related to the increase in ROS scavenging enzyme activity. This may provide a new method for increasing seed germination under stress environments, and may be an excellent model system for the study of cross-tolerance.
Mei, Yu-qin; Song, Song-quan
Microsoft Academic Search
The effects of gibberellic acid, kinetin, benzyladenine, ethylene, 24- epibrassinolide and polyamines (spermine, spermidine, putrescine, cadaverine) on jasmonic acid inhibition of seed germination and seedling growth of barley were studied. All of the plant growth regulators studied were determined to have a succesful performance in reversing of the inhibitory effects of jasmonic acid on the seed germination and seedling growth.
Kudret KABAR; Semra KILIÇ
Effects of late-terminal drought stress on seed germination and vigor of barley (Hordeum vulgare L.)
Late-terminal drought stress during grain filling has recently become more common in the semi-arid Mediterranean region, where barley (Hordeum vulgare L.) is grown as an important winter cereal crop. Little information is available in the literature about the effect of late-terminal drought stress on seed germination and vigor of barley. The objective of this experiment was to study the effect
Nezar Samarah; Ahmad Alqudah
Technology Transfer Automated Retrieval System (TEKTRAN)
Seed germination and early seedling growth is a complex biological process requiring closely coordinated expression of numerous genes and pathways. Gibberellin and abscisic acid play central roles in regulating seed germination. To gain insight into the global transcriptional control of seed germina...
Response to temperature stress of reactive oxygen species scavenging enzymes in the cross-tolerance of barley seed germination
A number of studies have shown the existence of cross-tolerance in plants, but the physiological mechanism is poorly understood.\\u000a In this study, we used the germination of barley seeds as a system to investigate the cross-tolerance of low-temperature pretreatment\\u000a to high-temperature stress and the possible involvement of reactive oxygen species (ROS) scavenging enzymes in the cross-tolerance.\\u000a After pretreatment at 0
Yu-qin Mei; Song-quan Song
Characterization of the entire cystatin gene family in barley and their target cathepsin L-like cysteine-proteases, partners in the hordein mobilization during seed germination.
Plant cystatins are inhibitors of cysteine-proteases of the papain C1A and legumain C13 families. Cystatin data from multiple plant species have suggested that these inhibitors act as defense proteins against pests and pathogens and as regulators of protein turnover. In this study, we characterize the entire cystatin gene family from barley (Hordeum vulgare), which contain 13 nonredundant genes, and identify and characterize their target enzymes, the barley cathepsin L-like proteases. Cystatins and proteases were expressed and purified from Escherichia coli cultures. Each cystatin was found to have different inhibitory capability against barley cysteine-proteases in in vitro inhibitory assays using specific substrates. Real-time reverse transcription-polymerase chain reaction revealed that inhibitors and enzymes present a wide variation in their messenger RNA expression patterns. Their transcripts were mainly detected in developing and germinating seeds, and some of them were also expressed in leaves and roots. Subcellular localization of cystatins and cathepsin L-like proteases fused to green fluorescent protein demonstrated the presence of both protein families throughout the endoplasmic reticulum and the Golgi complex. Proteases and cystatins not only colocalized but also interacted in vivo in the plant cell, as revealed by bimolecular fluorescence complementation. The functional relationship between cystatins and cathepsin L-like proteases was inferred from their common implication as counterparts of mobilization of storage proteins upon barley seed germination. The opposite pattern of transcription expression in gibberellin-treated aleurones presented by inhibitors and enzymes allowed proteases to specifically degrade B, C, and D hordeins stored in the endosperm of barley seeds. PMID:19759340
Martinez, Manuel; Cambra, Ines; Carrillo, Laura; Diaz-Mendoza, Mercedes; Diaz, Isabel
Of the four starch degrading enzymes in plants, only alpha-amylase and alpha-glucosidase have been extensively studied. Both alpha-amylase and alpha-glucosidase are important in germinating seeds in direct initiation of attack on starch grains. Five different alpha-glucosidases have been found in ...
Seed dormancy and germination
Seed dormancy and germination are complex adaptive traits of higher plants that are influenced by a large number of genes and environmental factors. Studies of genetics and physiology have shown the important roles of the plant hormones abscisic acid and gibberellin in the regulation of dormancy and germination. More recently, the use of quantitative genetics and mutant approaches has allowed
Maarten Koornneef; Leónie Bentsink; Henk Hilhorst
Barley seed proteomics from spots to structures.
Barley is a major cereal crop grown mainly for feed and malting. Two-dimensional gel electrophoresis has been used to analyse barley proteins for over 20 years and more recently, mass spectrometry was applied. In the absence of a genome sequence, barley gene and EST sequences combined with information from rice and other cereals facilitate identification of barley proteins. Several hundred barley seed proteins are identified and lower abundance proteins including membrane proteins are now being analysed. In the present review we focus on variation in protein profiles of seed tissues during grain filling, maturation, germination and radicle elongation. Cultivar comparisons and genetic mapping of polymorphic protein spots in doubled haploid populations provide a means to link the genome to the proteome and identify proteins that can influence grain quality. Many proteins appear in multiple forms on 2D-gels. Specific protein families, including peroxidases and alpha-amylases have been subjected to in-depth analysis resulting in characterisation of different isozymes, post-translational modifications and processing. A functional proteomics study focusing on the seed thioredoxin system has led to identification of thioredoxin target proteins, quantitative analysis of reduction of individual target disulphides and structural studies to gain insight into determinants for target protein recognition by thioredoxin. PMID:19118654
Finnie, Christine; Svensson, Birte
Transcriptional regulatory programs underlying barley germination and regulatory functions of Gibberellin and abscisic acid
Background Seed germination is a complex multi-stage developmental process, and mainly accomplished through concerted activities of many gene products and biological pathways that are often subjected to strict developmental regulation. Gibberellins (GA) and abscisic acid (ABA) are two key phytohormones regulating seed germination and seedling growth. However, transcriptional regulatory networks underlying seed germination and its associated biological pathways are largely unknown. Results The studies examined transcriptomes of barley representing six distinct and well characterized germination stages and revealed that the transcriptional regulatory program underlying barley germination was composed of early, late, and post-germination phases. Each phase was accompanied with transcriptional up-regulation of distinct biological pathways. Cell wall synthesis and regulatory components including transcription factors, signaling and post-translational modification components were specifically and transiently up-regulated in early germination phase while histone families and many metabolic pathways were up-regulated in late germination phase. Photosynthesis and seed reserve mobilization pathways were up-regulated in post-germination phase. However, stress related pathways and seed storage proteins were suppressed through the entire course of germination. A set of genes were transiently up-regulated within three hours of imbibition, and might play roles in initiating biological pathways involved in seed germination. However, highly abundant transcripts in dry barley and Arabidopsis seeds were significantly conserved. Comparison with transcriptomes of barley aleurone in response to GA and ABA identified three sets of germination responsive genes that were regulated coordinately by GA, antagonistically by ABA, and coordinately by GA but antagonistically by ABA. Major CHO metabolism, cell wall degradation and protein degradation pathways were up-regulated by both GA and seed germination. Those genes and metabolic pathways are likely to be important parts of transcriptional regulatory networks underlying GA and ABA regulation of seed germination and seedling growth. Conclusions The studies developed a model depicting transcriptional regulatory programs underlying barley germination and GA and ABA regulation of germination at gene, pathway and systems levels, and established a standard transcriptome reference for further integration with various -omics and biological data to illustrate biological networks underlying seed germination. The studies also generated a great amount of systems biological evidence for previously proposed hypotheses, and developed a number of new hypotheses on transcriptional regulation of seed germination for further experimental validation.
Characterization of the Entire Cystatin Gene Family in Barley and Their Target Cathepsin L-Like Cysteine-Proteases, Partners in the Hordein Mobilization during Seed Germination1[W
Plant cystatins are inhibitors of cysteine-proteases of the papain C1A and legumain C13 families. Cystatin data from multiple plant species have suggested that these inhibitors act as defense proteins against pests and pathogens and as regulators of protein turnover. In this study, we characterize the entire cystatin gene family from barley (Hordeum vulgare), which contain 13 nonredundant genes, and identify and characterize their target enzymes, the barley cathepsin L-like proteases. Cystatins and proteases were expressed and purified from Escherichia coli cultures. Each cystatin was found to have different inhibitory capability against barley cysteine-proteases in in vitro inhibitory assays using specific substrates. Real-time reverse transcription-polymerase chain reaction revealed that inhibitors and enzymes present a wide variation in their messenger RNA expression patterns. Their transcripts were mainly detected in developing and germinating seeds, and some of them were also expressed in leaves and roots. Subcellular localization of cystatins and cathepsin L-like proteases fused to green fluorescent protein demonstrated the presence of both protein families throughout the endoplasmic reticulum and the Golgi complex. Proteases and cystatins not only colocalized but also interacted in vivo in the plant cell, as revealed by bimolecular fluorescence complementation. The functional relationship between cystatins and cathepsin L-like proteases was inferred from their common implication as counterparts of mobilization of storage proteins upon barley seed germination. The opposite pattern of transcription expression in gibberellin-treated aleurones presented by inhibitors and enzymes allowed proteases to specifically degrade B, C, and D hordeins stored in the endosperm of barley seeds.
The effects of salinity and osmotic stress on barley germination rate: sodium as an osmotic regulator
Background and Aims Seed germination is negatively affected by salinity, which is thought to be due to both osmotic and ion-toxicity effects. We hypothesize that salt is absorbed by seeds, allowing them to generate additional osmotic potential, and to germinate in conditions under which they would otherwise not be able to germinate. Methods Seeds of barley, Hordeum vulgare, were germinated in the presence of either pure water or one of five iso-osmotic solutions of polyethylene-glycol (PEG) or NaCl at 5, 12, 20 or 27 °C. Germination time courses were recorded and germination indices were calculated. Dry mass, water content and sodium concentration of germinating and non-germinating seeds in the NaCl treatments at 12 °C were measured. Fifty supplemental seeds were used to evaluate the changes in seed properties with time. Key Results Seeds incubated in saline conditions were able to germinate at lower osmotic potentials than those incubated in iso-osmotic PEG solutions and generally germinated faster. A positive correlation existed between external salinity and seed salt content in the saline-incubated seeds. Water content and sodium concentration increased with time for seeds incubated in NaCl. At higher temperatures, germination percentage and dry mass decreased whereas germination index and sodium concentration increased. Conclusions The results suggest that barley seeds can take up sodium, allowing them to generate additional osmotic potential, absorb more water and germinate more rapidly in environments of lower water potential. This may have ecological implications, allowing halophytic species and varieties to out-compete glycophytes in saline soils.
Zhang, Hongxiang; Irving, Louis J.; McGill, Craig; Matthew, Cory; Zhou, Daowei; Kemp, Peter
Purification and partial characterization of a 31-kDa cysteine endopeptidase from germinated barley
Proteolytic enzymes hydrolyze cereal seed storage proteins into small peptides and amino acids, which are very important for seed germination and the malting process. A cysteine-class endopeptidase was purified from 4-d-germinated barley (Hordeum vulgare L. cv. Morex). Four purification steps were used, carboxymethyl cellulose cation-exchange chromatography, chromatofocusing, size-exclusion chromatography, and electroelution from a polyacrylamide gel. The endopeptidase was most active
Ningyan Zhang; Berne I. Jones
Physiological Basis of Seed Germination.
National Technical Information Service (NTIS)
This is the first collection of studies on the various aspects of seed germination to be published in Soviet literature. Works of practical significance have been given primary consideration: the presowing treatment of seeds to improve their quality and t...
K. E. Ovcharov
Saatgutvitalität von elektronenbehandeltem Getreidesaatgut im Kalttest Seed vitality of electron treated grain in cold-test germination
behandlung Abstract: To examine the use of low energy electrons as a method of seed dressing in ecologi- cal agriculture, especially concerning its influence on seed vitality, samples of wheat, rye and barley were investigated by testing germination vigour under cold stress and by Bio crystallisation methods. Lowered germination speed indicated a decrease of seed vitality. Alterations of growth, like
C. Matthes; U. Geier
QTLs in barley controlling seedling elongation of deep-sown seeds
In drought areas, in which topsoil moisture is low, barley seeds are generally sown in the subsoil (deep-seeding). In order\\u000a for the shoots of germinating seeds to emerge from the deep soil cover, the coleoptile and the first internode of the seedlings\\u000a must elongate as an adaptive response to deep-seeding. Here, we have mapped quantitative trait loci (QTLs) for these
H. Takahashi; M. Noda; K. Sakurai; A. Watanabe; H. Akagi; K. Sato; K. Takeda
Winery wastewater inhibits seed germination and vegetative growth of common crop species.
The ability to reuse winery wastewater would be of significant benefit to the wine industry, as it could potentially be a cost-effective method of wastewater management, whilst at the same time providing a valuable water resource. This study investigated the effects of different dilutions of a semi-synthetic winery wastewater on the growth and germination of four common crop species in a glasshouse study; barley (Hordeum vulgare), millet (Pennisetum glaucum), lucerne (Medicago sativa) and phalaris (Phalaris aquatica). The wastewater caused a significant delay in the germination of lucerne, millet and phalaris, although overall germination percentage of all species was not affected. Vegetative growth was significantly reduced in all species, with millet being the most severely affected. The germination index of barley correlated very highly (r(2)=0.99) with barley biomass, indicating that barley seed germination bioassays are highly relevant to plant growth, and therefore may be of use as a bioassay for winery wastewater toxicity. PMID:20452120
Mosse, Kim P M; Patti, Antonio F; Christen, Evan W; Cavagnaro, Timothy R
7 CFR 201.54 - Number of seeds for germination.
Code of Federal Regulations, 2010 CFR
... false Number of seeds for germination. 201.54 Section 201.54...FEDERAL SEED ACT REGULATIONS Germination Tests in the Administration of...201.54 Number of seeds for germination. At least 400 seeds shall...
Proteomics of rice seed germination.
Seed is a condensed form of plant. Under suitable environmental conditions, it can resume the metabolic activity from physiological quiescent status, and mobilize the reserves, biosynthesize new proteins, regenerate organelles, and cell membrane, eventually protrude the radicle and enter into seedling establishment. So far, how these activities are regulated in a coordinated and sequential manner is largely unknown. With the availability of more and more genome sequence information and the development of mass spectrometry (MS) technology, proteomics has been widely applied in analyzing the mechanisms of different biological processes, and proved to be very powerful. Regulation of rice seed germination is critical for rice cultivation. In recent years, a lot of proteomic studies have been conducted in exploring the gene expression regulation, reserves mobilization and metabolisms reactivation, which brings us new insights on the mechanisms of metabolism regulation during this process. Nevertheless, it also invokes a lot of questions. In this mini-review, we summarized the progress in the proteomic studies of rice seed germination. The current challenges and future perspectives were also discussed, which might be helpful for the following studies. PMID:23847647
He, Dongli; Yang, Pingfang
Seed germination as a thermobiological problem.
Thermal effects on seed germination are considered through the changes brought about by temperature in the germination capacity, in the germination rate, and in the distribution of the relative frequency of germination along the incubation times. A number of questions of general thermobiological interest are thus raised, entailing the need of an analysis of the temperature dependence of the seed germination rate. A treatment of these rates by the activation-energy approach cannot be general, for their Arrhenius plots are not always linear. Moreover, it is shown that any process displaying a temperature optimum (as happens in the germination of most seed species) cannot follow one of the fundamental tenets of the collision rate theory. The need of a theoretical treatment stressing the essential role of the partition of energy within the seed system has led to an anlysis using the absolute reaction rate theory. New experimental prospects for the physiology of seed germination are thus raised, concerning the meaning of the temperature cardinal points, the growth pattern of the embryo in germinating seeds, the dual effect of protein thermodenaturation, the effects of high hydrostatic pressures, and a whole pharmacological line of work. The cybernetic counterpart of the thermodynamic view of seed germination appears in the study of the distribution of the relative frequency of germination along the isothermal incubation time. In some species of seeds the thermal communication between the environment and the seed growth effector can be shown to proceed by molecular collisions at all germination isotherms. In the seeds of Dolichos biflorus this communication through random thermal noise prevails only at temperatures close to both extreme limits of germination. Both in this species and in Calotropis procera there is a temperature range (encompassing the optimum) within which a temperature signal is superimposed upon the gaussian noise. An interpretation is proposed according to which the temperature signal is transduced in a protein-conformation code. PMID:756055
Labouriau, L G
Stimulation of Lettuce Seed Germination by Ethylene.
Ethylene increased the germination of freshly imbibed lettuce (Lactuca sativa L. var. Grand Rapids) seeds. Seeds receiving either red or far-red light or darkness all responded positively to the gas. However, ethylene was apparently without effect on dorm...
F. B. Abeles J. Lonski
7 CFR 201.53 - Source of seeds for germination.
... false Source of seeds for germination. 201.53 Section 201.53...FEDERAL SEED ACT REGULATIONS Germination Tests in the Administration of...201.53 Source of seeds for germination. (a) When both purity...
Physicochemical changes of oat seeds during germination
The physicochemical properties of native and germinated oat seeds cultivated in China and their correlations were investigated. The growth curve during germination of oat seeds was described. The malt yield was 84% at the end of malting. The losses by removing of shoots and rootlets were the major cause of the total dry matter losses in the last 24h of
Binqiang Tian; Bijun Xie; John Shi; Jia Wu; Yan Cai; Tuoming Xu; Sophia Xue; Qianchun Deng
Seed germination characteristics of Halogeton glomeratus
Halogeton glomeratus (Bieb.) C.A. Mey, an annual forb in the family Chenopodiaceae, is widely distributed in the inland salt deserts of western North America. Experiments were conducted to determine the effects of NaCl and temperature on seed germination and the recovery of germination responses after transfer to distilled water. Seeds of H. glomeratus were germinated at various temperature regimes (5-15°C,
M. Ajmal Khan; Bilquees Gul; Darrell J. Weber
First off the mark: early seed germination.
Most plant seeds are dispersed in a dry, mature state. If these seeds are non-dormant and the environmental conditions are favourable, they will pass through the complex process of germination. In this review, recent progress made with state-of-the-art techniques including genome-wide gene expression analyses that provided deeper insight into the early phase of seed germination, which includes imbibition and the subsequent plateau phase of water uptake in which metabolism is reactivated, is summarized. The physiological state of a seed is determined, at least in part, by the stored mRNAs that are translated upon imbibition. Very early upon imbibition massive transcriptome changes occur, which are regulated by ambient temperature, light conditions, and plant hormones. The hormones abscisic acid and gibberellins play a major role in regulating early seed germination. The early germination phase of Arabidopsis thaliana culminates in testa rupture, which is followed by the late germination phase and endosperm rupture. An integrated view on the early phase of seed germination is provided and it is shown that it is characterized by dynamic biomechanical changes together with very early alterations in transcript, protein, and hormone levels that set the stage for the later events. Early seed germination thereby contributes to seed and seedling performance important for plant establishment in the natural and agricultural ecosystem. PMID:21430292
Weitbrecht, Karin; Müller, Kerstin; Leubner-Metzger, Gerhard
Corn Seed Germination and Vigor Following Freezing during Seed Development
The potential for an early autumn frost to reduce corn (Zea mays L.) seed quality is a concern for seed producers. This study evaluated the effect of freezing rate, freezing temperature (26, 211C) and duration (4, 6 h), ear attachment, and endosperm composition on seed germination and vigor (accelerated aging (AA) and cold test) during seed development and maturation of
James Woltz; Dennis M. TeKrony; Dennis B. Egli
Soluble sugar availability of aerobically germinated barley, oat and rice coleoptiles in anoxia
Physiological and metabolic responses to anoxia were compared for aerobically germinated seedlings of barley (Hordeum vulgare), oat (Avena sativa) and rice (Oryza sativa). Coleoptile growth of barley, oat and rice seedlings was suppressed by a 24h-anoxic stress, but the growth of the rice coleoptiles was much greater than that of the barley and oat coleoptiles. ATP concentration in the anoxic
Hisashi Kato-Noguchi; Yukihiro Yasuda; Ryosuke Sasaki
Alkaloid Changes in Tobacco Seeds during Germination.
Nicotine, nornicotine, anabasine, and anatabine, normally found in growing and mature tobacco (Nicotiana tabacum L.) plants, were extracted and quantified from mature tobacco seeds and young tobacco seedlings. The rate of net alkaloid disappearance and accumulation in tobacco seedlings was related to phases of germination.In general, the increased rate of germination associated with higher temperatures also increased the rate of initial loss of alkaloids and the subsequent rate of accumulation of alkaloids. Maximum alkaloid accumulation in 144-hour-old seedlings cultured with 10-hour day occurred at 27 C. Following an 8-hour photoinduction period, seeds germinated in darkness accumulated greater amounts of alkaloids than seeds exposed to light each day. Seeds germinated in darkness for 96 hours, following the 8-hour photoinduction period, and then exposed to light each day accumulated the greatest amounts of alkaloids. PMID:16658655
Weeks, W W; Bush, L P
Allelopathic effects of weeds extracts against seed germination of some plants.
This study investigated the allelopathic effects of various weeds extracts on seed germination of 11 crop species. Most of the weed extracts tested had inhibitory effects on seed germination of common bean, tomato, pepper, squash, onion, barley, wheat, and corn at different application rates as compared with the 10% acetone control. Chickpea seed germination was inhibited by extracts of Solanum nigrum L., Chenopodium album L., and Matricaria chamomilla L. (10%, 20% and 22.5%, respectively) at the end of 21 day incubation period. However, Glycyrrhiza glabra L., Sorghum halepense (L.) Pers., and Reseda lutea L. extracts stimulated chickpea seed germination at the rates of 95%, 94%, and 93%, respectively, compared to control. It was concluded that some of the weed extracts tested in this study could be used as inhibitor while others could be used as stimulator for the crops. PMID:16161968
Kadioglu, Izzet; Yanar, Yusuf; Asav, Unal
Effects of bird ingestion on seed germination of Sorbus commixta
To determine the effects of ingestion by birds on seed germination, we performed germination experiments in the field and\\u000a laboratory with Sorbus commixta. The germination of four groups of seeds was compared: ingested seeds, seeds defecated in feces after feeding of fruits to\\u000a birds; extracted seeds, seeds deliberately extracted from the fruit pulp; juiced seeds, seeds plus the juice of
Tsutomu Yagihashi; Mitsuhiro Hayashida; Toshizumi Miyamoto
Interaction of microwaves and germinating seeds
SciTech Connect
The preliminary investigation measured the internal metabolic process by ATP production. Leakage of ions and organic material from germinating seeds indicated that membranes are a target of microwaves and heat. Electron photo-micrographs showed an increase in damage to membranes as heat and microwave treatments were increased. The second phase of this investigation was concerned with determining some of the biological activity at the initiation of germination of wheat seed, Triticum aestivum L., using a resonating microwave cavity oscillating at 9.3 GHz as a probe. Direct current conductivity measurements were also made on the seeds as a means of confirming the observations made with the microwave cavity.
Shafer, F.L.
Exudation of an allelopathic substance lepidimoide from seeds during germination
Lepidimoide promotes growth of the cockscomb hypocotyl. It is exuded from germinating seeds of various plant species into their culture environment. The mode of exudation of lepidimoide from seeds into the culture solution, using sunflower and buckwheat seeds, was studied in relation to seed germination. In the dry seeds, about 75% of the lepidimoide was found in the seed coat
Kosumi Yamada; Seiji Kosemura; Shosuke Yamamura; Koji Hasegawa
Amino Acid Composition of Germinating Cotton Seeds
Total and free amino acid composition of germinating cotton seeds (Gossypium hirsutum L.) was determined. The germinating seeds were separated into cotyledon and developing axis fractions daily and the composition of each tissue was summed to get the whole seed composition. By separating the developing seeds into these two tissue fractions, and determining total and free amino acids, a balance sheet was developed for each amino acid. This technique allowed changes in distribution with time of each amino acid to be followed in each tissue. Data for total content and amount in protein of each amino acid are presented. Asparagine increased in the whole seed, and most of this increase was found in the free pool of the developing axis. Other amino acids (e.g. arginine, glutamic acid) increased in the free pool but showed an over-all decrease, indicating that they were being metabolized. Amino acid contents of storage and nonstorage protein isolates were determined.
Elmore, C. Dennis; King, Earl E.
Seed Germination and Seedling Survival of Spartina alterniflora Loisel
Spartina alterniflora (smooth cordgrass) is a widespread intertidal salt marsh plant that is frequently used in coastal restoration projects. Seeds collected in 2004 were tested for seed germination and seedling survival after 6 months of cold seed storage to determine differences among collection locations (experiment 1). Seeds collected in 2005, after Hurricane Katrina, were tested for seed germination and seedling
Patrick D. Biber; John D. Caldwell
Seed germination ecology in southwestern Western Australia
Germination responses of species from the native plant communities of southwestern Western Australia can be related to syndromes\\u000a of life history, fire response, and seed storage, and also to factors related to environmental stress. The Mediterranean-type\\u000a climate of the region with periodic drought and recurrent fires affects the production of viable seeds in plants of limited\\u000a stature and rooting depth.
David T. Bell; Julie A. Plummer; Susan K. Taylor
We assessed the global regulation of gene expression from seed to seed during barley (Hordeum vulgare L.) development by quantifying transcript abundance in key tissues and developmental stages of two diverse genotypes using the Barley1 GeneChip. Differential abundance was observed both between tis...
The role of alpha-glucosidase in germinating barley grains.
The importance of ?-glucosidase in the endosperm starch metabolism of barley (Hordeum vulgare) seedlings is poorly understood. The enzyme converts maltose to glucose (Glc), but in vitro studies indicate that it can also attack starch granules. To discover its role in vivo, we took complementary chemical-genetic and reverse-genetic approaches. We identified iminosugar inhibitors of a recombinant form of an ?-glucosidase previously discovered in barley endosperm (ALPHA-GLUCOSIDASE97 [HvAGL97]), and applied four of them to germinating grains. All four decreased the Glc-to-maltose ratio in the endosperm 10 d after imbibition, implying inhibition of maltase activity. Three of the four inhibitors also reduced starch degradation and seedling growth, but the fourth did not affect these parameters. Inhibition of starch degradation was apparently not due to inhibition of amylases. Inhibition of seedling growth was primarily a direct effect of the inhibitors on roots and coleoptiles rather than an indirect effect of the inhibition of endosperm metabolism. It may reflect inhibition of glycoprotein-processing glucosidases in these organs. In transgenic seedlings carrying an RNA interference silencing cassette for HvAgl97, ?-glucosidase activity was reduced by up to 50%. There was a large decrease in the Glc-to-maltose ratio in these lines but no effect on starch degradation or seedling growth. Our results suggest that the ?-glucosidase HvAGL97 is the major endosperm enzyme catalyzing the conversion of maltose to Glc but is not required for starch degradation. However, the effects of three glucosidase inhibitors on starch degradation in the endosperm indicate the existence of unidentified glucosidase(s) required for this process. PMID:21098673
Stanley, Duncan; Rejzek, Martin; Naested, Henrik; Smedley, Mark; Otero, Sofía; Fahy, Brendan; Thorpe, Frazer; Nash, Robert J; Harwood, Wendy; Svensson, Birte; Denyer, Kay; Field, Robert A; Smith, Alison M
Interaction of light and hormone signals in germinating seeds
Seed germination is regulated by several environmental factors, such as moisture, oxygen, temperature, light, and nutrients.\\u000a Light is a critical regulator of seed germination in small-seeded plants, including Arabidopsis and lettuce. Phytochromes,\\u000a a class of photoreceptors, play a major role in perceiving light to induce seed germination. Classical physiological studies\\u000a have long suggested the involvement of gibberellin (GA) and abscisic
Mitsunori Seo; Eiji Nambara; Giltsu Choi; Shinjiro Yamaguchi
7 CFR 201.31 - Germination standards for vegetable seeds in interstate commerce.
...2010-01-01 false Germination standards for vegetable seeds in interstate commerce...Seeds § 201.31 Germination standards for vegetable seeds in interstate commerce. The following germination standards for vegetable seeds in interstate...
...2009-01-01 false Germination standards for vegetable seeds in interstate commerce...Seeds § 201.31 Germination standards for vegetable seeds in interstate commerce. The following germination standards for vegetable seeds in interstate...
Protein repair L-isoaspartyl methyltransferase in plants. Phylogenetic distribution and the accumulation of substrate proteins in aged barley seeds.
Protein L-isoaspartate (D-aspartate) O-methyltransferases (MTs; EC 18.104.22.168) can initiate the conversion of detrimental L-isoaspartyl residues in spontaneously damaged proteins to normal L-aspartyl residues. We detected this enzyme in 45 species from 23 families representing most of the divisions of the plant kingdom. MT activity is often localized in seeds, suggesting that it has a role in their maturation, quiescence, and germination. The relationship among MT activity, the accumulation of abnormal protein L-isoaspartyl residues, and seed viability was explored in barley (Hordeum vulgare cultivar Himalaya) seeds, which contain high levels of MT. Natural aging of barley seeds for 17 years resulted in a significant reduction in MT activity and in seed viability, coupled with increased levels of "unrepaired" L-isoaspartyl residues. In seeds heated to accelerate aging, we found no reduction of MT activity, but we did observe decreased seed viability and the accumulation of isoaspartyl residues. Among populations of accelerated aged seed, those possessing the highest levels of L-isoaspartyl-containing proteins had the lowest germination percentages. These results suggest that the MT present in seeds cannot efficiently repair all spontaneously damaged proteins containing altered aspartyl residues, and their accumulation during aging may contribute to the loss of seed viability.
Mudgett, M B; Lowenson, J D; Clarke, S
Effect of salicylic acid and salt on wheat seed germination
The effects of pretreatment with salicylic acid on wheat seed germination (Triticum aestivum L. cv. Roshan), lipid peroxidation, and superoxide dismutase, catalase, polyphenol oxidase, and peroxidase activity were studied under conditions of salt stress. Seeds treated with different concentrations of salicylic acid were used for measuring germination traits. Salt stress was induced by sodium chloride solution. Seeds were soaked in
Aria Dolatabadian; Seyed Ali Mohammad Modarres Sanavy; Mozafar Sharifi
Autotoxic inhibition of seed germination by Typha latifolia : an evaluation
Seeds of Typha latifolia were exposed to leaf extracts, leaf pieces, and soil water from adult plants of T. latifolia. In liquid culture, only extracts of concentration greater than or equal to 3% (dry weight to volume) inhibited seed germination. Adding soil to the liquid cultures increased the inhibition of seed germination by extracts. The inhibitory effects of extracts were
James B. Grace
Evidence that the Adverse Effect of Urea Fertilizer on Seed Germination in Soil is Due to Ammonia Formed through Hydrolysis of Urea by Soil Urease
Studies using seeds of wheat (Triticum aestivum L.), rye (Secale cereale L.), barley (Hordeum vulgare L.), and corn (Zea mays L.) indicated that the adverse effect of urea fertilizer on seed germination in soil is due to ammonia formed through hydrolysis of urea by soil urease and is not due to urea itself, to urea fertilizer impurities such as biuret,
John M. Bremner; Michael J. Krogmeier
Hydrogen sulfide promotes wheat seed germination under osmotic stress
Effects of NaHS, H2S donor, on germination and antioxidant metabolism in wheat (Triticum aestivum L.) seeds under osmotic stress were investigated. With the enhancement of osmotic stress, which was mimicked by PEG-6000,\\u000a the seed germination dropped gradually. NaHS treatment could promote wheat seed germination against osmotic stress in a dose-dependent\\u000a manner; while Na+ and other sulfur-containing components, such as S2?,
H. Zhang; M. J. Wang; L. Y. Hu; S. H. Wang; K. D. Hu; L. J. Bao; J. P. Luo
Seed germination in temperate rain forest species of southern Chile: chilling and gap-dependency germination
Canopy gap and chilling requirements for seed germination were assessed in 61 and 44 species, respectively, in the temperate\\u000a rain forest of southern Chile. Germination assays within canopy gap and understorey were carried out under natural conditions.\\u000a Germination tests in cold stratified and non-stratified seeds were performed under laboratory conditions. Seeds were collected\\u000a of common trees, shrubs, vines and perennial
Javier A. Figueroa
Seed germination characteristics of Chrysothamnus nauseosus ssp. viridulus (Astereae, Asteraceae)
Rubber rabbitbrush (Chrysothamnus nauseosus (Pallas) Britt. ssp. viridulus) may prove to be a source of high-quality cis-isoprene rubber, but its establishment is limited by a lack of information on seed germination. Consequently, seeds were germinated at alternating temperatures (5-15, 5-25, 15-25, and 20-30 C) in light and dark as well as constant temperatures (15-40 C with 5-C increments) to determine temperature response. Seeds were also germinated in solutions of polyethylene glycol 6000, salinity regimes at all the above-mentioned temperatures to determine salinity and temperature interaction. The hormones GA/sub 3/ and kinetin were used to study their effect on overcoming salt- and temperature-induced germination inhibition. Seeds of C. nauseosus ssp. viridulus were very sensitive to low temperature. Best germination was achieved at 25 and 30 C, but these seeds also germinated at a higher temperature (35 C). The seeds of rabbit brush germinated at both constant and alternating temperatures. Light appears to play little or no role in controlling germination of the seeds of rubber rabbitbrush. However, seeds of rabbitbrush were sensitive to salinity, and seed germination was progressively inhibited by increase in salt concentration, although a few seeds still germinated at the highest saline level. Progressively higher concentrations of polyethylene glycol also progressively inhibited germination. Suppression of seed germination induced by high salt concentrations and high temperatures can be partially alleviated by the application of either GA/sub 3/ or kinetin. 34 references, 5 figures, 3 tables.
Khan, M.A.; Sankhla, N.; Weber, D.J.; McArthur, E.D.
Immunological screening for specific protein content in barley seeds
A screening method employing immunofluorescence has been developed to judge the amount of specific polypeptides, such as the\\u000a high lysine protein chymotrypsin inhibitor 2 (CI-2) in the endosperm of barley.\\u000a \\u000a Thin sections or sanded seeds were prepared fixed in 4% paraformaldehyde and labelled with antibody against CI-2 conjugated\\u000a with fluorescein isothiocyanate. With this technique single seeds can be evaluated without
Ulla Rasmussen
Dual regulation of seed germination by smoke solutions
The stimulation of seed germination by smoke and aqueous smoke extractshas received much attention in recent years. However, the mode of action andtheidentity of the active compound(s) in smoke which promote seed germinationremain unknown. Consequently, experiments were conducted to gain furtherinsightinto the nature of smoke-stimulated seed germination, using Grand Rapidslettuceseeds. Imbibition of seeds prior to incubation with diluted smoke extract,resulted
M. E. Light; M. J. Gardner; A. K. Jäger; J. van Staden
Underdeveloped embryos and germination in Aristolochia galeata seeds.
Aristolochiaceae have been described as having seeds with underdeveloped embryos and morphological or morphophysiological dormancy. Aristolochia galeata is a native climber found in the Cerrado biome, associated with road and gallery forest edges. The aims of this study were to investigate: embryo growth rate, morphology and seed germination parameters under different treatments. Embryos were excised to obtain embryo length at four stages: initial, seeds after coat rupture, radicle tip protrusion and cotyledon emergence from the seed coat. Germination tests were conducted at 30 °C under three nitrate concentrations (1, 10 and 20 mM), fluctuating temperature (27/20 °C) and light and dark conditions. We found that seeds have underdeveloped embryos, which take about 301 ± 178 h (±SD) to achieve seed coat rupture, another 205 ± 126 h to reach radicle protrusion and 176 ± 76 h more to the final stage of cotyledon emergence. Germinability was above 52% in all treatments, except in the dark (15%). For all treatments, average germination time was above 290 ± 123 h. Potassium nitrate increased germinability to >87%. No particular treatment was required for embryo development, but seeds in the population that continued to germinate after 1 month were probably in various states of non-deep, simple morphophysiological dormancy. Increased germinability in nitrate treatments and light requirement for germination could prevent germination under unsuitable environmental conditions and be a strategy to increase seedling establishment in the cerrado. PMID:21134093
Alves-Da-Silva, D; Borghetti, F; Thompson, K; Pritchard, H; Grime, J P
Investigating the Influence of Karrikins on Seed Germination
ERIC Educational Resources Information Center
|Recent research has identified a karrikin (a butenolide derative) known as 3-methyl-2H-furo[2,3-c]pyran-2-one, formed from burning cellulose, that stimulates seed germination. Here, I present ideas on how to investigate the influence of karrikins on seed germination in the laboratory.|
de Beer, Josef
Salinity and Temperature Effects on Seed Germination of Milk Thistle
Milk thistle [Silybum marianum (L.) Gaertn] is an annual plant belonging to the Asteraceae family whose ripe seeds contain flavonoid substances, which are important in the modern pharmaceutical industry. Seed germination is a major factor limiting the establishment of plants under saline conditions. The effect of salinity and temperatures on germination and seedling establishment was studied in two genotypes of
N. Ghavami; A. A. Ramin
Salinity can affect germination of seeds either by creating osmotic potentials that prevent water uptake or by toxic effects of specific ions. This work was carried out to evaluate the germination of sunflower (Helianthus annuus L.) seeds under increasing salinity by using the most abundant salts in China. Potassium (K), sodium (Na), and calcium (Ca) contents in hypocotyls were determined
Daowei Zhou; Moxin Xiao
An Overview of Enhancement of Triploid Watermelon Seed Germination
The weight of the tetraploid coat of the dry triploid watermelon seed is not reduced by tumbling, but cryptic changes increase the ability of the embryo to germinate more quickly. Germination, as measured by radicle emergence, was evaluated after a number of treatments designed to mechanically scarify the seed coat were used. In addition, hydrochloric acid, which can eliminate serious
B. B. Rhodes; C. O. Huey Jr; A. Abramovich; T. B. Platt
Germination of Redberry Juniper (Juniperus pinchotii) Seed in Western Texas
ABSTRACT , Weinvestigated germination\\/seedling emergencecharacteristics of redberry juniper (Juniperus pinchotii Sudw.) seeds harvested in December 1993 from 20 trees in the central Edwards Plateau and in December 1996 from 21 trees. Germination of seeds collected from raccoon (Procyon lotor) and ,bird (American robin [Turdus migratorius] and cedar waxwing [Bombycilla cedrorum]) feces in the northwestern Edwards Plateau in December 1996 were
Joseph L. Petersen; Darrell N. Ueckert; Charles A. Taylor; Keith R. Shaffer
Phytotoxicity of nanoparticles: Inhibition of seed germination and root growth
Plants need to be included to develop a comprehensive toxicity profile for nanoparticles. Effects of five types of nanoparticles (multi-walled carbon nanotube, aluminum, alumina, zinc, and zinc oxide) on seed germination and root growth of six higher plant species (radish, rape, ryegrass, lettuce, corn, and cucumber) were investigated. Seed germination was not affected except for the inhibition of nanoscale zinc
Daohui Lin; Baoshan Xing
Characteristics of the active transport of peptides and amino acids by germinating barley embryos
Use of two different assays involving either radioactively labelled substrates or a fluorescent-labelling procedure, gave good agreement for the rates of transport of peptides and amino acids into the scutellum of germinating grains of barley (Hordeum vulgare cv. Maris Otter, Winter). However, evidence was obtained for the enzymic decarboxylation of transpored substrate, which can cause underestimates of transport rates when
D. J. Walker-Smith; J. W. Payne
Protein mobilization and malting-specific proteinase expression during barley germination
Robust barley was germinated under three different conditions: 1) a production run in a commercial malting facility, 2) a micromalting protocol developed to generate malt with malting quality metrics similar to that from the commercial malting, and 3) a simple laboratory setting using a humidified ...
Apoptosis in barley aleurone during germination and its inhibition by abscisic acid
During germination of barley grains, DNA fragmentation was observed in the aleurone. The appearance of DNA fragmentation in the aleurone layer, observed by TUNEL staining in aleurone sections, started near the embryo and extended to the aleurone cells far from the embryo in a time dependent manner. The same spatial temporal activities of hydrolytic enzymes such as a-amylase were observed
Mei Wang; Berry J. Oppedijk; Xin Lu; Bert Van Duijn; Rob A. Schilperoort
Inhibitive effects of barley (Hordeum vulgare) on germination and growth of seedling quack grass (Agropyrum repens)
Allelopathy is defined as the direct or indirect harmful or beneficial effects of one plant on another through the release of chemical compounds into the environment. Barley (Hordeum vulgare) contains water soluble allelochemicals that inhibit the germination and growth of other species. This characteristic could be used in weed management programmes. Greenhouse and laboratory experiments were conducted to determine (i)
Study of allelopathical effects of barley on inhibition of germination and growth of seedling green foxtail
Allelopathy is defined as the direct or indirect harmful or beneficial effects of one plant on another through the release of chemical compounds into the environment. Barley (Hordeum vulgare) contains watersoluble allelochemicals that inhibit the germination and growth of other species. This characteristic could be used in weed management programs. Greenhouse and laboratory experiments were conducted to determine the effects
Zoheir Y Ashrafi; Sedigheh Sadeghi; Hamid R Mashhadi; Hassa M Alizade
Seed germination of the halophyte Suaeda japonica under salt stress
Suaeda japonica Makino belonging to the family Chenopodiaceae, is a halophyte and grows at the shore of Ariake sea in Japan. This plant presumably\\u000a possesses high salt resistant nature, thus, we examined the mechanisms of seed germination under salt stress. The seeds maintained\\u000a 80% germination rates on the medium containing 0.7 M NaCl. Germination rates varied depending on salt type;
Takaharu Yokoishi; Shizufumi Tanimoto
Allelopathy due to purine alkaloids in tea seeds during germination
Summary During imbibition of whole tea seeds (6 days) two purine alkaloids, caffeine and theobromine, did not decrease in the seed\\u000a coats and there was no increase in the seeds. In parallel with and after the breaking of seed coats there was a gradual release\\u000a of caffeine from coats of germinating seeds. By contrast, when the seed was freed from the
T. Suzuki; G. R. Waller
Soluble sugar availability of aerobically germinated barley, oat and rice coleoptiles in anoxia.
Physiological and metabolic responses to anoxia were compared for aerobically germinated seedlings of barley (Hordeum vulgare), oat (Avena sativa) and rice (Oryza sativa). Coleoptile growth of barley, oat and rice seedlings was suppressed by a 24 h-anoxic stress, but the growth of the rice coleoptiles was much greater than that of the barley and oat coleoptiles. ATP concentration in the anoxic rice coleoptiles was greater than that in the anoxic barley and oat coleoptiles. Concentrations of ethanol and activity of alcohol dehydrogenase (ADH) in the anoxic rice coleoptiles were also greater than those of the anoxic barley and oat coleoptiles, suggesting that ethanolic fermentation may be more active in the rice coleoptiles than in the barley and oat coleoptiles, where glycolysis and ethanolic fermentation are the main source of ATP production. Soluble sugar concentration in the anoxic rice coleoptiles was greater than that of the anoxic barley and oat coleoptiles. However, ?-amylase, which catabolizes reserve starch to soluble sugars, was active in anoxic barley, oat and rice endosperms, and soluble sugar concentration in the anoxic barley, oat and rice endosperms was not significantly different. Therefore, anoxia stress may inhibit soluble sugar transport from the endosperms to the coleoptiles in barley and oat more than in rice. Since the availability of soluble sugar is essential for operation of glycolysis and fermentation in plant cells, ability for sugar transport from the endosperms to the coleoptiles may be one means to distinguish the coleoptile growth of these plant species in anoxia and anoxia tolerance of these plants. PMID:20727618
Kato-Noguchi, Hisashi; Yasuda, Yukihiro; Sasaki, Ryosuke
Precocious Germination during In Vitro Growth of Soybean Seeds 1
Immature Glycine max (L.) Merrill seeds were grown and matured in liquid medium at 25°C under fluorescent light. In standard medium containing minerals, 146 millimolar sucrose and 62.5 millimolar glutamine (osmolality 0.24), precocious germination seldom occurred with a starting seed size of less than 300 milligrams fresh weight. Frequency of precocious germination increased with increased starting seed size. Sucrose concentration strongly affected precocious germination while glutamine concentration had no effect. Starting with 300 to 350 milligrams fresh weight seeds, treatments which reduced the sucrose concentration or lowered the osmolality of the culture medium stimulated precocious germination, and increased the fresh weight growth but not the dry weight growth of seeds. Increasing the osmolality to 0.38 with sucrose or mannitol prevented precocious germination without reducing dry weight accumulation in seeds. In medium with initially low osmolality, precocious germination was inhibited by addition of 1 to 100 micromolar abscisic acid to the medium without a reduction in seed growth. During growth and maturation of large soybean seeds in vitro, precocious germination and other abnormal tissue growth can be prevented by high sucrose or mannitol concentrations in the medium or by addition of abscisic acid.
Obendorf, Ralph L.; Wettlaufer, Scott H.
Volatile Metabolites Controlling Germination in Buried Weed Seeds
Velvetleaf (Abutilon theophrasti Medic), morning glory (Ipomoea purpurea [L.] Roth), and wild mustard (Brassica kaber [D.C.] L. C. Wheeler) seeds exhibited decreased germination with increased planting depth in soil. Flushing the soil for 2 minutes each day with air overcame the inhibition. A sealed in vitro system was used to sample the volatile components produced by weed seeds. Inhibition of seed germination was accompanied by decreased O2 levels and production of volatile metabolites identified as acetaldehyde, ethanol, and acetone. The effectiveness of these compounds in reducing germination was dependent on O2 levels.
Holm, Robert E.
Effects of UV-irradiation on seed germination.
The advent of depletion of the ozone layer with the reported subsequent increase of UV-irradiation has led to heightened interest in the effects of UV light on cellular organisms. In this study, the effects of UV-irradiation was studied on the germination of kale, cabbage, radish and agave seeds. In all cases, UV light sped the germination of these seeds but the subsequent growth of the seedlings was markedly retarded. Pictures, taken at day 15, are presented to show this latter effect and the possible effects of UV-irradiation on seed germination are discussed. PMID:12462583
Noble, Rudolf E
Plant hormone interactions during seed dormancy release and germination
This review focuses mainly on eudicot seeds, and on the interactions between abscisic acid (ABA), gibber- ellins (GA), ethylene, brassinosteroids (BR), auxin and cytokinins in regulating the interconnected molecular processes that control dormancy release and germi- nation. Signal transduction pathways, mediated by environmental and hormonal signals, regulate gene expression in seeds. Seed dormancy release and germination of species with coat
Birgit Kucera; Marc Alan Cohn; Gerhard Leubner-Metzger
Trace gas emissions and smoke-induced seed germination
Dormant seeds of a California chaparral annual were induced to germinate by smoke or paper. Nitrogen oxides induced 100 percent vapors emitted from smoke-treated sand or treated water samples inducing. Smoke germination in a manner similar to smoke germination were comparable in acidity and concentration of nitrate and nitrite to nitrogen dioxide (NOâ)-treated samples. Vapors from smoke-treated and NOâ-treated filter
Jon E. Keeley; C. J. Fotheringham
Quaking Aspen--Seed Germination and Early Seedling Growth.
Although freshly dispersed aspen seeds germinate quickly and nearly completely over a broad range of temperatures, early growth of seedlings is highly sensitive to availability of water, temperature, and physical and chemical conditions of the seedbed.
W. T. McDonough
Improving Seed Germination of Saltgrass under Saline Conditions
Saltgrass (Distichlis spicata var. stricta (Greene)) has a great potential for use as a turfgrass and as a revegetation species of saline sites. Experi- ments were conducted to test the effect of the application of different concentrations of ethep- hon, fusicoccin, kinetin, thiourea, and Proxy on saltgrass seed germination under three salinity levels. Saltgrass germination percentage was 56% under nonsaline
M. A. Shahba; Y. L. Qian; K. D. Lair
Salinity and seed germination patterns in coastal plants
The seed germination behaviour of a number of coastal species suggests that they can be separated into three categories, whose response to salinity shows some correlation with habitat. All but two germinated well in fresh water. After immersion for several days in 1\\/2, full, and 1 1\\/2 strength seawater all recover at least partly. Dune species are more adversely affected
S. R. J. Woodell
Phytochromes differentially regulate seed germination responses to light quality and temperature cues during seed maturation.
The ratio of red to far-red light (R : FR) experienced by seeds during maturation affects germination, but the genetic regulation of this effect is poorly understood. In Arabidopsis thaliana, responses to R : FR are governed by five phytochrome photoreceptors, PHYA-PHYE. PHYA, PHYB and PHYE mediate germination, but their roles in germination response to the seed maturation environment are largely unknown. Seeds of A. thaliana phytochrome mutants and natural accessions were matured in a factorial combination of cold (16 degrees C) and warm (24 degrees C) temperatures and high (R : FR = 1) and low (R : FR = 0.6) R : FR environments, resembling sunlight and foliar shade, respectively. Germination was observed in resulting seeds. All five phytochromes mediated germination responses to seed maturation temperature and/or R : FR environment. PHYA suppressed germination in seeds matured under cold temperature, and PHYB promoted germination under the same conditions. PHYD and PHYE promoted germination of seeds matured under warm temperature, but this effect diminished when seeds matured under reduced R : FR. The A. thaliana natural accessions exhibited interesting variation in germination responses to the experimental conditions. Our results suggest that the role of individual PHY loci in regulating plant responses to R : FR varies depending on temperature and provide novel insights into the genetic basis of maternal effects. PMID:19453482
Dechaine, Jennifer M; Gardner, Gary; Weinig, Cynthia
Diallel cross analysis of seed germination traits in sugar beet
A diallel cross design, involving six diploid O-type lines and their cytoplasmic male sterile (CMS) equivalents was used to\\u000a examine the genetic control of characters determining seed viability and vigor of seed and seedling in sugar beet. Six characters\\u000a including percentage of germination, seedling establishment, weight of 1000 germs, seedling vigor, speed of germination, and\\u000a monogermity were analyzed. Additive genetic
S. Y. Sadeghian; H. Khodaii
Proteomic analysis of Arabidopsis seed germination and priming
To better understand seed germination, a complex developmental process, we developed a proteome analysis of the model plant Arabidopsis for which complete genome sequence is now available. Among about 1,300 total seed proteins resolved in two-dimensional gels, changes in the abundance (up- and down-regulation) of 74 proteins were observed during germination sensu stricto (i.e. prior to radicle emergence) and the
Karine Gallardo; Claudette Job; Steven P. C. Groot; Magda Puype; Hans Demol; Joel Vandekerckhove; Dominique Job
Gibberellin Biosynthesis and Response during Arabidopsis Seed Germination
The hormone-mediated control of plant growth and development involves both synthesis and response. Previous studies have shown that gibberellin (GA) plays an essential role in Arabidopsis seed germination. To learn how GA stimulates seed germination, we performed comprehensive analyses of GA biosynthesis and response using gas chromatography-mass spectrometry and oligonucleotide-based DNA microarray analysis. In addition, spatial correlations between GA biosynthe-
Mikihiro Ogawa; Atsushi Hanada; Yukika Yamauchi; Ayuko Kuwahara; Yuji Kamiya; Shinjiro Yamaguchi
Limit dextrinase from germinating barley has endotransglycosylase activity, which explains its activation by maltodextrins
Limit dextrinase (EC 188.8.131.52) from germinating barley ( Hordeum vulgare L) can be activated by millimolar concentrations of linear maltodextrins with a degree of polymerisation = 2. The activation was assay-dependent; it was detected using assays based on the solubilisation of cross-linked dyed pullulan but not in assays that directly measured cleavage events such as the formation of new reducing
Gordon J. McDougall; Heather A. Ross; J. Stuart Swanston; Howard V. Davies
Changes in RNA and Protein Metabolism Associated with Alterations in the Germination Efficiency of Sunflower Seeds
Precise knowledge of seed quality after harvest and during storage is of particular importance for seed producers. We analysed different sunflower seed lots (Helianthus annuusL.) characterized by extremes of germination ability. We used RNA analysis to study possible changes in gene expression in seeds unable to germinate. Total RNA content was very small in dry seeds showing a low germination
The role of the GA signaling SLY1 in Arabidopsis seed germination
Seed dormancy, afterripening, and germination are complex developmental process regulated by phytohormones. The phytohormone abscisic acid (ABA) is needed to set up seed dormancy during embryo maturation whereas gibberellin (GA) stimulates seed germination. In tomato and Arabidopsis, GA is clearly ...
Studies on palms: Fruits, seeds and seed germination in the genus Phoenix L
The paper gives an account of the morphology and anatomy of fruits, seeds and their germination in the genusPhoenix. The fruit is an oblong, 1-seeded berry, yellowish-black to dark purple in colour. The seed is hard and stony, grooved on\\u000a ventral side. Embryo lies dorsally opposite the groove. Germination is hypogeal, eligulate and remotive.\\u000a \\u000a Many palm fruits and seeds are
N. V. Biradar; T. S. Mahabale
A RING finger E3 ligase gene, Oryza sativa Delayed Seed Germination 1 (OsDSG1), controls seed germination and stress responses in rice
Seed germination is an important character for plant growth and seed quality. We identified a rice mutant that was delayed\\u000a in its germination. There, T-DNA was inserted into Oryza sativa Delayed Seed Germination 1 (OsDSG1), causing a recessive null mutation. Overexpression of the gene enhanced seed germination. OsDSG1 is most similar to Arabidopsis AIP2, an E3 ligase targeting ABI3.Yeast two-hybrid
Gi-Gyeong Park; Jong-Jin Park; Jinmi Yoon; Sun-Nam Yu; Gynheung An
Effect of seed stimulation on germination and sugar beet yield
NASA Astrophysics Data System (ADS)
Germination and sugar beet yield after seed stimulation were investigated. The seeds came from the energ'hill technology and were subject to laser irradiation. The experiments were conducted in the laboratory and field conditions. Lengthening of germinal roots and hypocotyls was observed. A positive effect of the stimulation on the morphological features was observed for the Eh seeds and laser irradiation applied in a three-fold dose. The energ'hill seeds exhibited a significantly higher content of carotenoids in seedlings and an increase in the content of chlorophylls. Laser light irradiation favourably modified the ratio of chlorophyll a to b. The leaves and roots of plants developed from the energ'hill and irradiated seeds were characterized by higher dry matter content thanin non-stimulated seeds. Seed stimulation had a positive influence on yielding and the saccharose content.
Prooeba-Bia?czyk, U.; Szajsner, H.; Grzyoe, E.; Demczuk, A.; Saca?a, E.; B?k, K.
Proteins induced by salt stress in tomato germinating seeds
Salt effects on protein synthesis in tomato germinating seeds were investigated by two-dimensional polyacrilamide gel electrophoresis of proteins labeled in vivo with ({sup 35}S)-Methionine. Seeds germinating in NaCl were analyzed at three germination stages (4mm long radicals, 15mm long radicles and expanding cotyledons) and compared to those germinating in water. At the first germination stage several basic proteins of M.W. 13Kd, 16Kd, 17Kd and 18Kd were detected in only salt germinating seeds. Other basic proteins of M.W. 12Kd, 50Kd and 54Kd were salt-induced at the second and third stage of germination. One 14Kd acid protein is observed in every assayed stage and shows several phosphorylated forms. The levels of expression of these proteins are directly correlated to assayed NaCl concentrations. All of these proteins, except 17Kd, are also induced by abscisic acid (ABA) in the same germination stages. A cooperative effect on the synthesis of these proteins is observed when both ABA and NaCl are present.
Torres-Shumann, S.; Godoy, J.A.; del Pozo, O.; Pintor-Toro, J.A. (Instituto Recursos Naturales y Agrobiologia, Sevilla (Spain))
Dormant seeds of a California chaparral annual were induced to germinate by smoke or paper. Nitrogen oxides induced 100 percent vapors emitted from smoke-treated sand or treated water samples inducing. Smoke germination in a manner similar to smoke germination were comparable in acidity and concentration of nitrate and nitrite to nitrogen dioxide (NO{sub 2})-treated samples. Vapors from smoke-treated and NO{sub 2}-treated filter paper had comparable NO{sub 2} flux rates. Chaparral wildfires generate sufficient nitrogen oxides from combustion of organic matter or from postfire biogenic nitrification to trigger germination of Emmerianthe penduliflora. Nitrogen oxide-triggered germination is not the result of changes in imbibition, as is the case with heat stimulated seeds.
Keeley, J.E.; Fotheringham, C.J. [Occidental College, Los Angeles, CA (United States)
Amylolytic activity in germinated Agrostemma githago L. seeds
The perisperm of seeds of Agrostemma githago contains starch reserves which constitute 40% of the dry weight of the mature seed. These starch reserves were mostly broken down between 48 and 96 h after initiation of imbibition. (Germination occurred after 24 h.) The mode of starch degradation showed close parallels with the breakdown of the starchy endosperm in cereals. Thus,
G. J. Klerk; P. Willekens; H. Kok; J. V. Jacobsen
Action of plant growth regulators and salinity on seed germination of Ceratoides lanata
Ceratoides lanata (Pursh) J.T. Howell is a shrub with numerous annual branchlets from the family Chenopodiaceae and is widely distributed in brackish water playas of northern Utah. Seeds had no dormancy, and about 90% of the seeds germinated in nonsaline control. Seed germination decreased with the increase in salinity, and more than 10% of the seeds germinated at 900 mmol\\/L
Inhibition of seed germination by quinolizidine alkaloids
Germination of Lactuca sativa L. was inhibited by mixtures of quinolizidine alkaloids. The alkaloid esters resulted in the strongest inhibition: 6 mM 13-tigloyloxylupanine inhibited germination by 100%, whereas the other lupin alkaloids, such as lupanine and sparteine, gave a 45 and 20% inhibition, respectively. Seedlings of Lupinus albus L., which are not affected by quinolizidine alkaloids, excrete lupanine and 13-tigloyloxylupanine
Michael Wink
Temperature and seed weight affect the germination of peach rootstock seeds and the growth of rootstock seedlings
Seeds of five cultivars of peach rootstocks were assessed to determine the effect of seed quality and temperature on germination and seedling growth. The weight of each seed and its surrounding endocarp was determined. Based on weight, the seeds were divided into four quartiles, stratified, and grown at 23°C with a 16h photoperiod. The percentage of seeds germinating over an
P. J Malcolm; P Holford; W. B McGlasson; S Newman
Effect of pre-germination treatments on seed physiology and germination of central Himalayan oaks?
The continuous decline in regeneration of two important species of central Himalayan oak, namely Quercus glauca and Q. leucotrichophora, is of great concern. A study was therefore, carried out to improve germination ability of these species using various presoaking treatments. Seeds of both the species lost viability following storage; tetrazolium staining pattern and germination capacity of seeds following different period of storage at 4 °C and 20 °C indicated retainment of viability for a period of 12 months at 4 °C. Of the various physical, chemical and plant growth regulator treatments examined to improve seed germination, only KNO3 1.0 % was found to be effective. Seeds scarified at the chalazal end exhibited significant improvement in germination in both the species (94.4 % compared to 56.7 % in control in Q. glauca and 82.7 % compared to 64.0 % in control in Q. leucotrichophora). The results of this study impart simple methods to improve seed germination for developing nurseries for commercial purposes. PMID:23572942
Purohit, Vijay K; Palni, L M S; Nandi, Shyamal K
Triacylglycerol and polar lipid metabolism in germinating sea buckthorn seeds
Dark germination of sea buckthorn (Hippophal rhamnoides L.) seeds was characterized by an initial 3-day-long lag-period, when the contents of triacylglycerols (TAGs) and polar lipids\\u000a (PLs) remained nearly the same due to a retardation in lipid metabolization. Subsequently, TAG content declined rapidly, and\\u000a by the 10th day of germination, it did not exceed 5% of total lipids. In this case,
A. G. Vereshchagin; N. N. Sidorova; V. P. Pchelkin; V. D. Tsydendambaev
Seed germination of roundleaf buffaloberry (Shepherdia rotundifolia ...
US Forest Service ... It was hypothesized that traditional growing substrates high in organic matter may impede their germination; ... (Shepherdia argentea) were sown in three substrates differing in organic matter and drainage properties.
Intrapopulation variation in Abutilon theophrasti seed mass and its relationship to seed germinability
The relationship between seed mass variation and germinability in ten Abutilon theophrasti Medic. plants from a single agricultural population was examined under controlled environmental conditions. Seeds were collected in the autumn of 1995 and dry-stored in paper bags at 4°C until the start of trials in the spring of 1998. For each plant, between 549 and 1000 randomly selected seeds
Hameed A. Baloch; Antonio DiTommaso; Alan K. Watson
Isolation and characterization of the gene encoding the starch debranching enzyme limit dextrinase from germinating barley.
The gene encoding the starch debranching enzyme limit dextrinase, LD, from barley (Hordeum vulgare), was isolated from a genomic phage library using a barley cDNA clone as probe. The gene encodes a protein of 904 amino acid residues with a calculated molecular mass of 98.6 kDa. This is in agreement with a value of 105 kDa estimated by SDS-PAGE. The coding sequence is interrupted by 26 introns varying in length from 93 bp to 825 bp. The 27 exons vary in length from 53 bp to 197 bp. Southern blot analysis shows that the limit dextrinase gene is present as a single copy in the barley genome. Gene expression is high during germination and the steady state transcription level reaches a maximum at day 5 of germination. The deduced amino acid sequence corresponds to the protein sequence of limit dextrinase purified from germinating malt, as determined by automated N-terminal sequencing of tryptic fragments coupled with matrix assisted laser desorption mass spectrometry. The sequenced peptide fragments cover 70% of the entire protein sequence, which shows 62% and 77% identity to that of starch debranching enzymes from spinach and rice and 37% identity to Klebsiella pullulanase. Sequence alignment supports the multidomain architecture and identifies both secondary structure elements of the catalytic (beta/alpha)8-barrel substrate, catalytic residues, and specificity associated motifs characteristic of members of the glycoside hydrolase family 13 which cleave alpha-1,6-glucosidic bonds. A remarkable distribution of the secondary structure elements to individual exons is observed. PMID:10350630
Kristensen, M; Lok, F; Planchot, V; Svendsen, I; Leah, R; Svensson, B
Gibberellic acid-mediated salt signaling in seed germination.
Seed germination initiates the postembryonic development of plants, which determines successful seedling establishment and plant propagation. It is therefore tightly regulated by diverse environmental conditions, including high salinity and drought, as well as by intrinsic developmental programs, among which gibberellic acid (GA) is best understood. Regulatory roles of GA in seed germination have been extensively studied. It is also known that high salinity inhibits germination by repressing genes encoding GA biosynthetic enzymes. However, it is still unclear how salt signals are coordinately incorporated into the GA signaling pathway at the molecular level. We recently demonstrated that a membrane-bound NAC transcription factor, NTL8, mediates salt signaling, primarily through a RGL2-independent GA pathway, in regulating seed germination. High salinity promotes NTL8 transcription and proteolytic activation of NTL8. Notably, the NTL8-mediated salt signaling is independent of abscisic acid (ABA). These observations indicate that membrane-mediated transcription control is an important component of salt signaling during seed germination. PMID:19704528
Kim, Sang-Gyu; Park, Chung-Mo
Gibberellic acid-mediated salt signaling in seed germination
Seed germination initiates the postembryonic development of plants, which determines successful seedling establishment and plant propagation. It is therefore tightly regulated by diverse environmental conditions, including high salinity and drought, as well as by intrinsic developmental programs, among which gibberellic acid (GA) is best understood. Regulatory roles of GA in seed germination have been extensively studied. It is also known that high salinity inhibits germination by repressing genes encoding GA biosynthetic enzymes. However, it is still unclear how salt signals are coordinately incorporated into the GA signaling pathway at the molecular level. We recently demonstrated that a membrane-bound NAC transcription factor, NTL8, mediates salt signaling, primarily through a RGL2-independent GA pathway, in regulating seed germination. High salinity promotes NTL8 transcription and proteolytic activation of NTL8. Notably, the NTL8-mediated salt signaling is independent of abscisic acid (ABA). These observations indicate that membrane-mediated transcription control is an important component of salt signaling during seed germination.
Kim, Sang-Gyu
Assessment of germination and vigour status of 24?year?old seeds of a Sophora hybrid
Germination and vigour of 24?year?old seeds collected from a single individual of a hybrid Sophora and stored at room temperature are compared with seeds from the 2001 season from the same tree. Germination of machine?cleaned seed showed the hard seed character was still evident after 24 yr. Hand?chipped seeds of the 2001 harvest gave 93% germination; 1977 seeds were 8%.
D. W. Fountain; C. R. McGill; R. C. Southward; R. V. Sproul; A. C. Mackay; H. A. Outred
Sycamore Seed Germination: The Effects of Provenance, Stratification, Temperature, and Parent Tree.
Various stratification periods and germination temperatures were applied0 sycamore seed collected along the Chattahoochee River from north Georgia to west Florida. Results showed that percent and speed of germination were greater for seed from southern th...
Effects of bird ingestion on seed germination of two Prunus species with different fruit-ripening seasons
To evaluate the effects of ingestion by birds on seed germination under natural conditions, we carried out germination experiments in the field using seeds of two Prunus species that have different fruit-ripening seasons. Germination of seeds with the following three treatments was compared: 'ingested seeds', seeds excreted after feeding of fruits to birds; 'extracted seeds', seeds deliberately extracted from the
????????????????????????????? ????? ???? ??? ??????????????????????? Genetic Control of Seed Weight, Size and Germination in Amoora polystachya
The study on seed morphology and genetic control of seed weight seed size and seed germination in Amoora polystachya was conducted using seeds collected from 10 seed trees each in natural forest in Kamphangphet and Tak provinces. The results showed that in one fruit contained 1-3 seeds whereas 1-2 seeds per 1 fruis was highest (77%) and in 100 fruits,
Suksan Saiwa; Prapai Kannark; Bundit Ponoy
Effect of seed passage through vertebrate frugivores' guts on germination: a review
The capacity of seeds to germinate after ingestion by frugivores is important for the population dynamics of some plant species and significant for the evolution of plant-frugivore interactions. In this paper the effects of different vertebrates on seed germination of nearly 200 plant species are reviewed, searching for patterns that predict the circumstances in which germination of seeds is enhanced,
Anna Traveset
Apomictic embryo development and survival in Uapaca kirkiana under in vitro and in vivo seed germination
In vitro and in vivo studies on seed germination of Uapaca kirkiana were conducted at Bunda College of Agriculture. In vitro germination treatments included two fruit sources (market and direct from trees); seed coat (outer and inner layers) removal and two seed germination media (Murashige and Skoog (MS) and woody plant medium (WPM)). Incubation of in vitro cultures was under
M. F. A Maliro; M. B Kwapata
7 CFR 201.29 - Germination of vegetable seed in containers of 1 pound or less.
...2009-01-01 2009-01-01 false Germination of vegetable seed in containers of 1...Labeling Vegetable Seeds § 201.29 Germination of vegetable seed in containers of 1...containers of 1 pound or less which have a germination equal to or better than the...
...2010-01-01 2010-01-01 false Germination of vegetable seed in containers of 1...Labeling Vegetable Seeds § 201.29 Germination of vegetable seed in containers of 1...containers of 1 pound or less which have a germination equal to or better than the...
Passage through bird guts causes interspecific differences in seed germination characteristics
Summary 1. Seed germination characteristics are often modified after seeds are ingested by frugivores. Factors that are intrinsic either to the plant or to the frugivore's digestive tract are responsible for the great variation observed in germination response. 2. Our objectives were to determine whether and how the seed germination patterns of five common western Mediterranean plant species are affected
A. Traveset; N. Riera; R. E. Mas
Seed longevity: survival and maintenance of high germination ability of dry seeds.
The seed constitutes the main vector of plant propagation and it is a critical development stage with many specificities. Seed longevity is a major challenge for the conservation of plant biodiversity and for crop success. Seeds possess a wide range of systems (protection, detoxification, repair) allowing them to survive in the dry state and to preserve a high germination ability. Therefore, the seed system provides an appropriate model to study longevity and aging. PMID:18926494
Rajjou, Loďc; Debeaujon, Isabelle
Ecophysiology of seed germination in Mediterranean geophytes. 1. Muscari spp
Ecophysiological aspects of seed germination were investigated in four Mediterranean geophytes of the genus Muscari (Liliaceae): M. comosum (tassel hyacinth), M. neglectum (common grape hyacinth), M. commutatum and M. weissii. Experiments were performed at constant temperatures in the dark and under temperature and light conditions simulating those prevailing in nature during November-January, i.e. well into the rainy season of the
Maria A. Doussi
Modeling the effect of density-dependent chemical interference upon seed germination.
A mathematical model is presented to estimate the effects of phytochemicals on seed germination. According to the model, phytochemicals tend to prevent germination at low seed densities. The model predicts that at high seed densities they may increase the probability of seed germination and the number of germinating seeds. Hence, the effects are reminiscent of the density-dependent effects of allelochemicals on plant growth, but the involved variables are germination probability and seedling number. The results imply that it should be possible to bypass inhibitory effects of allelopathy in certain agricultural practices and to increase the efficiency of nature conservation in several plant communities. PMID:18648596
Sinkkonen, Aki
A mathematical model is presented to estimate the effects of phytochemicals on seed germination. According to the model, phytochemicals tend to prevent germination at low seed densities. The model predicts that at high seed densities they may increase the probability of seed germination and the number of germinating seeds. Hence, the effects are reminiscent of the density-dependent effects of allelochemicals on plant growth, but the involved variables are germination probability and seedling number. The results imply that it should be possible to bypass inhibitory effects of allelopathy in certain agricultural practices and to increase the efficiency of nature conservation in several plant communities. PMID:19330163
Effects of Cadmium Stress on Seed Germination, Seedling Growth and Seed Amylase Activities in Rice ( Oryza sativa)
Two rice varieties, Xiushui 110 with high cadmium (Cd) tolerance and Xiushui 11 with low Cd tolerance were used to study the effects of Cd stress on seed germination, seedling growth and amylase activities. The low cadmium concentration had little effect on seed germination rate. However, cadmium stress could significantly inhibit plumule and radicle growth, especially for radicle growth. Germination
Jun-yu HE; Yan-fang REN; Cheng ZHU; De-an JIANG
Barley embryos in varying stages of development were subjected in situ ; to single doses of x radiation of 50 to 800 r. At intervals following ; irradiation, part of the developing grains were sampled for histologic ; examination; those remaining were allowed to mature so that effects of ; irradiation could be followed on their subsequent germination and seedling
Leo W. Mericle; Rae Phelps Mericle
Regulation of Avena Fatua Seed Germination by Smoke Solutions, Gibberellin A 3 and Ethylene
Dormant, intact Avena fatua L. (wild oat) seeds germinate poorly at 20 °C. Removing the hulls slightly increased germination. Treatment with smoke solutions\\u000a increased the germination of both intact seeds and caryopses. Exogenous GA3, alone or in the presence of smoke solution, increased the germination of caryopses, while ACC shows a tendency to increase\\u000a germination of caryopses only when applied in
J. K?pczy?ski; B. Bia?ecka; M. E. Light; J. van Staden
Effects of nitric oxide scavengers on thermoinhibition of seed germination in Arabidopsis thaliana
Plant seeds sometimes do not germinate at elevated temperature. The thermoinhibition mechanisms of seed germination have yet\\u000a not revealed. Here we describe a chemical approach to improve seed germination at high temperature. We compared the temperature\\u000a response of germination between wild-type Arabidopsis thaliana and its T-DNA insertion mutant ?AtGLB3 that lacks a functional gene encoding GLB3, a homologue of bacterial
K. K. Hossain; R. D. Itoh; G. Yoshimura; G. Tokuda; H. Oku; M. F. Cohen; H. Yamasaki
Effects of gut passage on seed germination: do experiments answer the questions they ask?
Summary 1. Frugivorous vertebrates may affect plant fitness by dispersing seeds to sites favour- able for establishment and by passing seeds through their gut, thereby altering germi- nation patterns. Although gut passage can inhibit germination, most studies have found that it improves germination rate and\\/or success. 2. However, studies that compare seeds passed through a gut to seeds directly removed
Factors affecting seed germination, seedling emergence, and survival of texasweed (Caperonia palustris)
Field, laboratory, and greenhouse experiments were conducted to determine the seed production potential and effect of environmental factors on germination, emergence, and survival of texasweed. Texasweed produced an average of 893 seed per plant, and 90% were viable. Seed exhibited dormancy, and prechilling did not release dormancy. Percent germination ranged from 56% for seed subjected to no prechilling to 1%
Clifford H. Koger; Krishna N. Reddy; Daniel H. Poston
Seed germination and life history syndromes in the California chaparral
USGS Publications Warehouse
Syndromes are life history responses that are correlated to environmental regimes and are shared by a group of species (Stebbins, 1974). In the California chaparral there are two syndromes contrasted by the timing of seedling recruitment relative to wildfires. One syndrome, here called the fire-recruiter or refractory seed syndrome, includes species (both resprouting and non-resprouting) which share the feature that the timing of seedling establishment is specialized to the first rainy season after fire. Included are woody, suffrutescent and annual life forms but no geophytes have this syndrome. These species are linked by the characteristic that their seeds have a dormancy which is readily broken by environmental stimuli such as intense heat shock or chemicals leached from charred wood. Such seeds are referred to as "refractory" and dormancy, in some cases, is due to seed coat impermeability (such seeds are commonly called hardseeded), but in other cases the mechanism is unknown. Seeds of some may require cold stratification and/or light in addition to fire related stimuli. In the absence of fire related cues, a portion or all of a species' seed pool remains dormant. Most have locally dispersed seeds that persist in the soil seed bank until the site burns. Dispersal of propagules is largely during spring and summer which facilitates the avoidance of flowering and fruiting during the summer and fall drought. Within a life form (e.g., shrub, suffrutescent, etc.), the seeds of these species have less mass than those of species with non-refractory seeds and this possibly reflects the environmental favorableness of the postfire environment for seedling establishment. Regardless of when fire occurs, germination is normally delayed until late winter or early spring. In the absence of fire, or other disturbance, opportunities for population expansion are largely lacking for species with this syndrome. The other syndrome, here called the fire-resister or non-refractory seed syndrome, includes species that are resilient to frequent fires (mostly by vegetative resprouting), but require fire-free periods for recruiting new seedlings. Included are shrubs, subshrubs, suffrutescents, lianas, geophytes and annuals. All are linked by the characteristic that their seeds germinate in the absence of cues related to wildfires. In many cases no form of seed dormancy is present and the seeds germinate soon after dispersal; consequently these species do not accumulate a persistent seed bank. Germination and seedling establishment is independent of fire and thus opportunities for population expansion are also independent of fire. The demographic pattern of seedling recruitment varies with the life form. For shrubs, seedling recruitment may be restricted to sites free of fire for periods of a hundred years or more. Recruitment appears to require relatively mesic conditions and this may account for the patchy distribution of these species within the matrix of relatively arid sites. Finding such sites has selected for propagules specialized for wind or animal dispersal; the majority are bird dispersed. These shrub species all disperse fruits in fall and winter and this may have been selected to take advantage of migratory birds as well as to time dispersal to the winter rains typical of the mediterranean-climate. Germination typically occurs within several weeks of the first fall or winter rains. Maturation of flowers and fruits during the summer and fall drought may account for the distribution of these species on more mesic sites. Seed mass of these species is large and this may have been selected to provide an advantage to seedlings establishing under the canopy of this dense shrub community.
Keeley, J. E.
12-oxo-phytodienoic acid accumulation during seed development represses seed germination in Arabidopsis.
Arabidopsis thaliana COMATOSE (CTS) encodes an ABC transporter involved in peroxisomal import of substrates for ?-oxidation. Various cts alleles and mutants disrupted in steps of peroxisomal ?-oxidation have previously been reported to exhibit a severe block on seed germination. Oxylipin analysis on cts, acyl CoA oxidase1 acyl CoA oxidase2 (acx1 acx2), and keto acyl thiolase2 dry seeds revealed that they contain elevated levels of 12-oxo-phytodienoic acid (OPDA), jasmonic acid (JA), and JA-Ile. Oxylipin and transcriptomic analysis showed that accumulation of these oxylipins occurs during late seed maturation in cts. Analysis of double mutants generated by crossing cts with mutants in the JA biosynthesis pathway indicate that OPDA, rather than JA or JA-Ile, contributes to the block on germination in cts seeds. We found that OPDA was more effective at inhibiting wild-type germination than was JA and that this effect was independent of CORONATINE INSENSITIVE1 but was synergistic with abscisic acid (ABA). Consistent with this, OPDA treatment increased ABA INSENSITIVE5 protein abundance in a manner that parallels the inhibitory effect of OPDA and OPDA+ABA on seed germination. These results demonstrate that OPDA acts along with ABA to regulate seed germination in Arabidopsis. PMID:21335376
Dave, Anuja; Hernández, M Luisa; He, Zhesi; Andriotis, Vasilios M E; Vaistij, Fabián E; Larson, Tony R; Graham, Ian A
Effect of salt stress on seed germination and seedling growth of three salinity plants.
Seeds of three halophyte species included Limonium sinense Kuntze, Glycine soja sieb. and Sorghum sudanense Stapf. were used to investigate the effects of different salinity concentrations on their germination percentage, germination energy, germination index, relative germination rate, relative salt-injury rate, radicle length and hypocotyl length. Results showed that seeds of G. soja can germinate well and rapidly at lower level of salt (< 200 mmol L(-1)), 50 mmol L(-1) salt concentrations is better to S. sudanense, suitable salt concentrations was beneficial to germinate of S. sudanense seeds. Seeds of L. sinense and S. sudanense can germinate at higher level of salt (400 mmol L(-1)). Three plant seeds had different physiological mechanism for germination under salt stress, radicle hypocotyl ratio of L. sinense and S. sudanense increased with increasing salt suggested that they had the higher tolerance in shoot growth under NaCl stress, which is perhaps the reason for their wide utilisation for saline soil rehabilitation. PMID:18819537
Li, Yan
Transcriptional dynamics of two seed compartments with opposing roles in Arabidopsis seed germination.
Seed germination is a critical stage in the plant life cycle and the first step toward successful plant establishment. Therefore, understanding germination is of important ecological and agronomical relevance. Previous research revealed that different seed compartments (testa, endosperm, and embryo) control germination, but little is known about the underlying spatial and temporal transcriptome changes that lead to seed germination. We analyzed genome-wide expression in germinating Arabidopsis (Arabidopsis thaliana) seeds with both temporal and spatial detail and provide Web-accessible visualizations of the data reported (vseed.nottingham.ac.uk). We show the potential of this high-resolution data set for the construction of meaningful coexpression networks, which provide insight into the genetic control of germination. The data set reveals two transcriptional phases during germination that are separated by testa rupture. The first phase is marked by large transcriptome changes as the seed switches from a dry, quiescent state to a hydrated and active state. At the end of this first transcriptional phase, the number of differentially expressed genes between consecutive time points drops. This increases again at testa rupture, the start of the second transcriptional phase. Transcriptome data indicate a role for mechano-induced signaling at this stage and subsequently highlight the fates of the endosperm and radicle: senescence and growth, respectively. Finally, using a phylotranscriptomic approach, we show that expression levels of evolutionarily young genes drop during the first transcriptional phase and increase during the second phase. Evolutionarily old genes show an opposite pattern, suggesting a more conserved transcriptome prior to the completion of germination. PMID:23858430
Dekkers, Bas J W; Pearce, Simon; van Bolderen-Veldkamp, R P; Marshall, Alex; Widera, Pawel; Gilbert, James; Drost, Hajk-Georg; Bassel, George W; Müller, Kerstin; King, John R; Wood, Andrew T A; Grosse, Ivo; Quint, Marcel; Krasnogor, Natalio; Leubner-Metzger, Gerhard; Holdsworth, Michael J; Bentsink, Leónie
Protein mobilization in germinating mung bean seeds involves vacuolar sorting receptors and multivesicular bodies.
Plants accumulate and store proteins in protein storage vacuoles (PSVs) during seed development and maturation. Upon seed germination, these storage proteins are mobilized to provide nutrients for seedling growth. However, little is known about the molecular mechanisms of protein degradation during seed germination. Here we test the hypothesis that vacuolar sorting receptor (VSR) proteins play a role in mediating protein degradation in germinating seeds. We demonstrate that both VSR proteins and hydrolytic enzymes are synthesized de novo during mung bean (Vigna radiata) seed germination. Immunogold electron microscopy with VSR antibodies demonstrate that VSRs mainly locate to the peripheral membrane of multivesicular bodies (MVBs), presumably as recycling receptors in day 1 germinating seeds, but become internalized to the MVB lumen, presumably for degradation at day 3 germination. Chemical cross-linking and immunoprecipitation with VSR antibodies have identified the cysteine protease aleurain as a specific VSR-interacting protein in germinating seeds. Further confocal immunofluorescence and immunogold electron microscopy studies demonstrate that VSR and aleurain colocalize to MVBs as well as PSVs in germinating seeds. Thus, MVBs in germinating seeds exercise dual functions: as a storage compartment for proteases that are physically separated from PSVs in the mature seed and as an intermediate compartment for VSR-mediated delivery of proteases from the Golgi apparatus to the PSV for protein degradation during seed germination. PMID:17322331
Wang, Junqi; Li, Yubing; Lo, Sze Wan; Hillmer, Stefan; Sun, Samuel S M; Robinson, David G; Jiang, Liwen
Effects of livestock on seed germination of guava ( Psidium guajava L.)
This paper reports on the effects that livestock have on seed germination of guava (Psidium guajava L.). Experiments here reported were intended to simulate gastric scarification using different soaking periods in a 0.01 N HCl solution alone or combined with rumen treatments. Additional experiments evaluated germination of defecated and nondefecated seeds germinated in petri dishes and in cow dung.
Eduardo Somarriba
Factors influencing seed germination of Cyperus capitatus, inhabiting the moving sand dunes in southern Europe
Cyperus capitatus Vandelli (Cyperaceae) is distributed in coastal sandy habitats and mobile dunes of south Europe. Its seed germination ecology is not known, despite its potential to be used in re-vegetation projects. Laboratory experiments were conduced to assess the effects of salinity, light regime, cold stratification and burial on seed germination of this species. Overall, increasing salinity delayed germination, increased
S. Redondo-Gómez; L. Andrades-Moreno; R. Parra; E. Mateos-Naranjo; A. M. Sánchez-Lafuente
Production of a recombinant full-length collagen type I alpha-1 and of a 45-kDa collagen type I alpha-1 fragment in barley seeds.
Recombinant DNA technology can be used to design and express collagen and gelatin-related proteins with predetermined composition and structure. Barley seed was chosen as a production host for a recombinant full-length collagen type I alpha1 (rCIa1) and a related 45-kDa rCIa1 fragment. The transgenic barley seeds were shown to accumulate both the rCIa1 and the 45-kDa rCIa1 fragment. Even when the amount of the rCIa1 was just above the detection threshold, this work using rCIa1 as a model demonstrated for the first time that barley seed can be used as a production system for collagen-related structural proteins. The 45-kDa rCI1a fragment expression, targeted to the endoplasmic reticulum, was controlled by three different promoters (a constitutive maize ubiquitin, seed endosperm-specific rice glutelin and germination-specific barley alpha-amylase fusion) to compare their effects on rCIa1 accumulation. Highest accumulation of the 45-kDa rCIa1 was obtained with the glutelin promoter (140 mg/kg seed), whereas the lowest accumulation was obtained with the alpha-amylase promoter. To induce homozygosity for stable 45-kDa rCIa1 production in the transgenic lines, doubled haploid (DH) progeny was generated through microspore culture. The 45-kDa rCIa1 expression levels achieved from the best DH lines were 13 mg/kg dry seeds under the ubiquitin promoter and 45 mg/kg dry seeds under the glutelin promoter. Mass spectroscopy and amino acid composition analysis of the purified 45-kDa rCIa1 fragment revealed that a small percent of prolines were hydroxylated with no additional detectable post-translational modifications. PMID:19656332
Eskelin, Katri; Ritala, Anneli; Suntio, Taina; Blumer, Susan; Holkeri, Heidi; Wahlström, Eva H; Baez, Julio; Mäkinen, Kristiina; Maria, Nuutila Anna
Azospirillum sp . inoculation in wheat, barley and oats seeds greenhouse experiments
The aim of the present work was to evaluate the inoculation effects of Azospirillum sp. RAM-7 strain, in seeds of wheat, barley and oats cultures on yield and total nitrogen content of the grains in greenhouse experiments. Seeds inoculation with Azospirillum sp. RAM-7 strain enhanced grain yields, even so, the responses vary among the evaluated cultures. For wheat, significant increases
Osmar R. Dalla Santa; Ramona Fernández Hernández; Gergina L. Michelena Alvarez; Pedro Ronzelli Junior; Carlos Ricardo Soccol
Seed treatment with Trichoderma harzianum alleviates biotic, abiotic, and physiological stresses in germinating seeds and seedlings.
Trichoderma spp. are endophytic plant symbionts that are widely used as seed treatments to control diseases and to enhance plant growth and yield. Although some recent work has been published on their abilities to alleviate abiotic stresses, specific knowledge of mechanisms, abilities to control multiple plant stress factors, their effects on seed and seedlings is lacking. We examined the effects of seed treatment with T. harzianum strain T22 on germination of seed exposed to biotic stress (seed and seedling disease caused by Pythium ultimum) and abiotic stresses (osmotic, salinity, chilling, or heat stress). We also evaluated the ability of the beneficial fungus to overcome physiological stress (poor seed quality induced by seed aging). If seed were not under any of the stresses noted above, T22 generally had little effect upon seedling performance. However, under stress, treated seed germinated consistently faster and more uniformly than untreated seeds whether the stress was osmotic, salt, or suboptimal temperatures. The consistent response to varying stresses suggests a common mechanism through which the plant-fungus association enhances tolerance to a wide range of abiotic stresses as well as biotic stress. A common factor that negatively affects plants under these stress conditions is accumulation of toxic reactive oxygen species (ROS), and we tested the hypothesis that T22 reduced damages resulting from accumulation of ROS in stressed plants. Treatment of seeds reduced accumulation of lipid peroxides in seedlings under osmotic stress or in aged seeds. In addition, we showed that the effect of exogenous application of an antioxidant, glutathione, or application of T22, resulted in a similar positive effect on seed germination under osmotic stress or in aged seed. This evidence supports the model that T. harzianum strain T22 increases seedling vigor and ameliorates stress by inducing physiological protection in plants against oxidative damage. PMID:20649416
Mastouri, Fatemeh; Björkman, Thomas; Harman, Gary E
The experiment was performed to study the germination of Vicia faba L. under the influence of cadmium (Cd) stress. Seeds were germinated for ten days by soaking in distilled water or cadmium nitrate solution. Germination rate, embryo radicle growth and water, Cd, and amino acid and sugar contents in cotyledons were investigated. Nutrient concentrations were also determined in the germination
S. Rahoui; A. Chaoui; E. El Ferjani
Germination of synthetic seeds of pineapple ( Ananas comosus L. Merr.)
. Tufts of multiple shoots were produced from dormant, axillary buds of pineapple in vitro. Tiny shoots (2-5 mm) isolated from the tuft of multiple shoots were encapsulated in 3% sodium alginate prepared using hormone-free Murashige and Skoog's basal medium, Murashige and Skoog's vitamins, 0.56 mM myo-inositol and 0.06 M sucrose. The encapsulated shoots represented synthetic seeds that germinated and
J. R. Soneji; P. S. Rao; M. Mhatre
Presoaking with hemin improves salinity tolerance during wheat seed germination
The aim of this study was to investigate whether presoaking with hemin, an inducer of heme oxygenase-1 (HO-1), could alleviate\\u000a salinity damage during wheat seed germination in comparison with the pretreatment of a well-known nitric oxide (NO) donor\\u000a sodium nitroprusside (SNP). The results showed that, compared with the samples upon 150 mM NaCl salt stress alone, both 10 ?M\\u000a hemin and 200 ?M
Sheng XuTianling; Tianling Lou; Nan Zhao; Yin Gao; Linghan Dong; Danjun Jiang; Wenbiao Shen; Liqin Huang; Ren Wang
Improvement of caper ( Capparis spinosa L.) seed germination by breaking seed coat-induced dormancy
Different dormancy-breaking pretreatments were assessed in order to improve germination of caper (Capparis spinosa L.) seeds. High germination percentages were obtained using concentrated sulfuric acid, followed by either a 90-min soaking procedure in a 100 ppm gibberellin (GA4 + 7) solution, or adding 0.2% potassium nitrate to the test substrate. Results obtained by means of a surgical treatment clearly suggest
Gabriel O. Sozzi; Angel Chiesa
Effects of different temperatures and duration on germination of caper (Capparis ovata) seeds.
Caperseed has poor germination because of the seed coat dormancy Germination of caperseeds are complex traits affected by a wide range of intemal and environmental influences. The effects of temperature preconditioning and period on germination of Capparis ovata were examined. Experiments were conducted in order to investigate germination behaviour of caperseeds subjected to different temperature and duration. The experiment revealed that the different temperature treatments were effective on mean germination percentage. The highest mean germination were obtained at 0 degree C 29.52% and 10 degrees C with 27.17% and the lowest mean germination were obtained at control seeds with 8.39%. Dry heat treatments effected germination rate, but it was not enough for removing germination obstacle of caper seed completely. PMID:20120507
Basbag, Mehmet; Toncer, Ozlem; Basbag, Sema
Transgenic barley expressing a protein-engineered, thermostable (1,3-1,4)-beta-glucanase during germination.
The codon usage of a hybrid bacterial gene encoding a thermostable (1,3-1,4)-beta-glucanase was modified to match that of the barley (1,3-1,4)-beta-glucanase isoenzyme EII gene. Both the modified and unmodified bacterial genes were fused to a DNA segment encoding the barley high-pI alpha-amylase signal peptide downstream of the barley (1,3-1,4)-beta-glucanase isoenzyme EII gene promoter. When introduced into barley aleurone protoplasts, the bacterial gene with adapted codon usage directed synthesis of heat stable (1,3-1,4)-beta-glucanase, whereas activity of the heterologous enzyme was not detectable when protoplasts were transfected with the unmodified gene. In a different expression plasmid, the codon modified bacterial gene was cloned downstream of the barley high-pI alpha-amylase gene promoter and signal peptide coding region. This expression cassette was introduced into immature barley embryos together with plasmids carrying the bar and the uidA genes. Green, fertile plants were regenerated and approximately 75% of grains harvested from primary transformants synthesized thermostable (1,3-1,4)-beta-glucanase during germination. All three trans genes were detected in 17 progenies from a homozygous T1 plant. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5
Jensen, L G; Olsen, O; Kops, O; Wolf, N; Thomsen, K K; von Wettstein, D
Proteomic analysis of seed germination under salt stress in soybeans.
Soybean (Glycine max (L.) Merrill) is a salt-sensitive crop, and its production is severely affected by saline soils. Therefore, the response of soybean seeds to salt stress during germination was investigated at both physiological and proteomic levels. The salt-tolerant cultivar Lee68 and salt-sensitive cultivar N2899 were exposed to 100 mmol/L NaCl until radicle protrusion from the seed coat. In both cultivars, the final germination percentage was not affected by salt, but the mean germination times of Lee68 and N2899 were delayed by 0.3 and 1.0 d, respectively, compared with controls. In response to salt stress, the abscisic acid content increased, and gibberellic acid (GA?+?) and isopentenyladenosine decreased. Indole-3-acetic acid increased in Lee68, but remained unchanged in N2899. The proteins extracted from germinated seeds were separated using two-dimensional gel electrophoresis (2-DE), followed by Coomassie brilliant blue G-250 staining. About 350 protein spots from 2-DE gels of pH range 3 to 10 and 650 spots from gels of pH range 4 to 7 were reproducibly resolved, of which 18 protein spots showed changes in abundance as a result of salt stress in both cultivars. After matrix-assisted laser desorption ionization-time of flight-mass spectroscopy (MALDI-TOF-MS) analysis of the differentially expressed proteins, the peptide mass fingerprint was searched against the soybean UniGene database and nine proteins were successfully identified. Ferritin and 20S proteasome subunit ?-6 were up-regulated in both cultivars. Glyceraldehyde 3-phosphate dehydrogenase, glutathione S-transferase (GST) 9, GST 10, and seed maturation protein PM36 were down-regulated in Lee68 by salt, but still remained at a certain level. However, these proteins were present in lower levels in control N2899 and were up-regulated under salt stress. The results indicate that these proteins might have important roles in defense mechanisms against salt stress during soybean seed germination. PMID:21726057
Xu, Xiao-yan; Fan, Rui; Zheng, Rui; Li, Chun-mei; Yu, De-yue
Interaction of accelerated aging and p-coumaric acid on crimson clover seed germination
Several phenolic acids, including p-coumaric acid, have been described as allelochemicals that may inhibit seed germination or seedling growth. Accelerated seed aging (high temperature (41 C) and high humidity (100%)) reduces germination and seedling vigor, and provides some indication as to seed g...
Seed Development and Germination in an Arabidopsis thaliana Line Antisense to Glutathione Reductase 2
Desiccating and germinating seeds are particularly prone to oxidative stress. Glutathione (GSH) is one of the most abundant and ubiquitous antioxidants in plants. To better understand GSH's role in developing and germinating seeds, wildtype (WT) and a line of seed antisense for glutathione reductase 2 (anGR2), one of two glutathione reductase (GR) genes characterized in the genetic model plant Arabidopsis
M. R. Sumugat; J. L. Donahue; D. F. Cortes; V. K. Stromberg; R. Grene; V. Shulaev; G. E. Welbaum
Effects of Seed Priming on Germination and Seedling Growth Under Water Stress in Rice
For disclosing the effects of seed priming with water and polyethylene glycol (PEG) on physiological characteristics in rice (Oryza sativa L.), the seeds of 4 rice cultivars were treated with H2O and different concentrations of PEG before germination. Primed or nonprimed (control) seeds were then germinated under drought stress conditions simulated with PEG in a serious of concentrations. The contents
Yuan-Yuan SUN; Yong-Jian SUN; Ming-Tian WANG; Xu-Yi LI; Xiang GUO; Rong HU; Jun MA
Effect of Salt Stress, Proline, and Polyamines on Seed Germination of Opuntia streptacantha
In this study we conducted experiments in order to determine whether polyamines (putrescine, spermidine, and spermine) and proline treatments help to break seed dormancy of Opuntia streptacantha and also if they facilitate seed germination under salt stress. The results showed that 1mM proline stimulated a better germination percentage as compared to untreated seeds, although the difference was not statistically significant.
Ana E. Ochoa-Alfaro; Claudia O. Silva-Ortega; Alicia Becerra-Flora; Joel Flores-Rivas; Juan F. Jiménez-Bremont
Effect of seed collection times and pretreatment methods on germination of Terminalia sericea Burch. ex DC
A nursery experiment was conducted to study the effects of seed collection times and pretreatment methods on the germination of Terminalia sericea Burch. ex DC. (Combretaceae). T. sericea is a multipurpose tree species occurring in the miombo woodlands whose seedling production is hampered by very low seed germination rate. Seeds were subjected to four treatment methods each at four different
Michael G. Likoswe; Joyce P. Njoloma; Weston F. Mwase; Clement Z. Chilima
Interactive effects of salt and alkali stresses on seed germination, germination recovery, and seedling growth of a halophyte Spartina alterniflora (Poaceae)
Soil salinization and alkalinization frequently co-occur in nature, but there is little information on the interactive effects of salt and alkali stresses on plants. Seed germination and early seedling growth are crucial stages for plant establishment. We investigated the interactive effects of salt and alkali stresses on seed germination, germination recovery and seedling growth of a halophyte Spartina alterniflora. Seed
R. Li; F. Shi; K. Fukuda
Internal dispersal of seeds by waterfowl: effect of seed size on gut passage time and germination patterns
Long distance dispersal may have important consequences for gene flow and community structure. The dispersal of many plants depends on transport by vertebrate seed dispersers. The shapes of seed shadows produced by vertebrates depend both on movement patterns of the dispersers and on the dynamics and effects of passage through the disperser's gut (i.e. the retention time, survival and germination of ingested seeds). A combination of experiments with captive waterbirds and aquatic plant seeds was used to analyse the following: (a) the effects of inter- and intra-specific variation in seed size and duck species on seed retention time in the gut and (b) the relationship between retention time and the percent germination and germination rates of seeds. Among the three Scirpus species used, those with smaller seeds showed higher survival after ingestion by birds and longer retention times inside their guts than those with larger seeds. For Potamogeton pectinatus, only seeds from the smaller size class (<8 mg) survived ingestion. Retention time affected the percent germination and germination rate of Scirpus seeds but in a manner that varied for the different plant and bird species studied. We recorded both linear and non-linear effects of retention time on percent germination. In addition, germination rate was positively correlated with retention time in Scirpus litoralis but negatively correlated in Scirpus lacustris. Small seed size can favour dispersal over larger distances. However, the effects of retention time on percent germination can modify the seed shadows produced by birds due to higher percent germination of seeds retained for short or intermediate periods. The changes in dispersal quality associated with dispersal distance (which is expected to be positively related to retention time) will affect the probability of seedling establishment over longer distances and, thus, the spatial characteristics of the effective seed shadow.
Figuerola, Jordi; Charalambidou, Iris; Santamaria, Luis; Green, Andy J.
Internal dispersal of seeds by waterfowl: effect of seed size on gut passage time and germination patterns.
Long distance dispersal may have important consequences for gene flow and community structure. The dispersal of many plants depends on transport by vertebrate seed dispersers. The shapes of seed shadows produced by vertebrates depend both on movement patterns of the dispersers and on the dynamics and effects of passage through the disperser's gut (i.e. the retention time, survival and germination of ingested seeds). A combination of experiments with captive waterbirds and aquatic plant seeds was used to analyse the following: (a) the effects of inter- and intra-specific variation in seed size and duck species on seed retention time in the gut and (b) the relationship between retention time and the percent germination and germination rates of seeds. Among the three Scirpus species used, those with smaller seeds showed higher survival after ingestion by birds and longer retention times inside their guts than those with larger seeds. For Potamogeton pectinatus, only seeds from the smaller size class (<8 mg) survived ingestion. Retention time affected the percent germination and germination rate of Scirpus seeds but in a manner that varied for the different plant and bird species studied. We recorded both linear and non-linear effects of retention time on percent germination. In addition, germination rate was positively correlated with retention time in Scirpus litoralis but negatively correlated in Scirpus lacustris. Small seed size can favour dispersal over larger distances. However, the effects of retention time on percent germination can modify the seed shadows produced by birds due to higher percent germination of seeds retained for short or intermediate periods. The changes in dispersal quality associated with dispersal distance (which is expected to be positively related to retention time) will affect the probability of seedling establishment over longer distances and, thus, the spatial characteristics of the effective seed shadow. PMID:20428840
Figuerola, Jordi; Charalambidou, Iris; Santamaria, Luis; Green, Andy J
Abscisic acid inhibits germination of mature Arabidopsis seeds by limiting the availability of energy and nutrients
. The addition of abscisic acid (ABA) to mature non-dormant seeds inhibits their germination. This effect of ABA might be related\\u000a to its natural function as an endogenous inhibitor of precocious germination during seed formation. In this work, we studied\\u000a how ABA affects the germination of mature seeds and the growth of nascent seedlings of Arabidopsisthaliana (L.) Heynh. Our findings
Alejandro Garciarrubio; Juan P. Legaria; Alejandra A. Covarrubias
Effect of salinity and chemical factors on seed germination in the halophyte Crithmum maritimum L
Seeds of the halophyte Crithmum maritimum L. were exposed to salt stress and chemical pretreatments in order to improve germination. Seeds submitted to salt stress\\u000a did not germinate but they recovered rapidly upon transfer to distilled water, recovery being higher after a low salinity\\u000a pretreatment. Chemical treatments resulted in differential effects on seed germination. Known dormancy breakers such as potassium
Laetitia Meot-Duros; Christian Magné
Factors and mechanisms influencing seed germination in a wetland plant sawgrass
Sawgrass (Cladium jamaicense) is the predominant plant and vegetation community in the Florida Everglades. Germination of sawgrass seeds in the laboratory\\u000a or nursery has been difficult and problematic, yet little is known about the physiological mechanistic regulation of the sawgrass\\u000a seed germination process. In the present study, we examined the factors and mechanisms that influence sawgrass seed germination.\\u000a We found
James Webb; ShiLi Miao; Xing-Hai Zhang
Seed germination of three species of Vallisneria (Hydrocharitaceae), and the effects of freshwater microalgae
Two experiments were conducted to investigate seed germination under natural temperature and light regimes and to evaluate the influence of freshwater microalgae on seed germination of threeVallisneria species. Seeds exposed to natural seasonal temperature and light changes for 24?months germinated only in spring, perhaps indicating an annual dormancy\\/non-dormancy cycle. The ecological background of the natural habitat seems to play predominant
Li Zhongqiang; Dan Yu; Tu Manghui
Dormancy patterns, germination ecology, and seed-bank types of twenty temperate fen grassland species
The germination ecology, including primary and secondary dormancy, mortality of seeds, and seed-bank type, of 20 fen grassland\\u000a species from Northern Germany was investigated using a combination of burial and germination experiments. To analyze primary\\u000a dormancy and effects of after-ripening (dry storage for 28 days) on freshly matured seeds, germination was measured at two\\u000a fluctuating temperature regimes (15\\/25°C and 5\\/15°C)
Kai Jensen
cis-4-Cyclohexene-1,2-dicarboximide: Inhibitor of phytochrome-promoted seed germination
cis-4-Cyclohexene-1,2-dicarboximide (CHDC) inhibits the germination of light-requiring seeds in both light and darkness but has no effect upon the germination of non-light-requiring seeds. In lettuce seeds, CHDC inhibits the action of far-red-absorbing form of phytochrome in breaking dormancy. This inhibition can be overcome by benzyladenine and red light together, but not by a combination of red light and gibberellic acid. Gibberellic acid-induced germination of lettuce seeds in darkness is inhibited also by CHDC. Embryos isolated from dark-imbibed lettuce seeds germinate on the inhibitor. CHDC was thought to be an "analogue" of cycloheximide, but it does not inhibit protein synthesis in lettuce seeds. Our results lead us to conclude that CHDC inhibits germination of seeds that require red light to break dormancy and interferes with some aspect of metabolism that is stimulated by far-red-absorbing form of phytochrome.
Bewley, J. Derek; Oaks, Ann
Effect of ?-ray irradiation on the germinating characteristics of wheat seed
Few researches have been reported on the long-term germination characteristics and the effect of high gamma radiation dose on cereal seeds. In this paper, to observe the effects of gamma irradiation (0-3 kGy) on the germination of wheat seed in long-term (within 20 months), wheat seed was dried after irradiation and the germination experiment during storage time was conducted. It was found that the lengths of buds of irradiated wheat seeds diminished, the roots of irradiated wheat seeds disappeared, and no germinations in irradiated wheat seed was found. The influence of ?-ray irradiation on roots was more significant than that on buds. After long-term storage, the germination of irradiated wheat seeds increased.
Wang, Jun; Yu, Yong; Tian, Xiaojing
Characterization of active dipeptide transport by germinating barley embryos: Effects of pH and metabolic inhibitors
A sensitive new fluorescent method is outlined for the study of peptide and amino acid transport processes. Studies on dipeptide transport in germinating barley (Hordeum vulgare.) embryos have provided evidence for accumulation of substrate against a concentration gradient, saturation kinetics, a pH optimum at pH 3.8, and inhibition by a variety of metabolic inhibitors. Acetate also inhibits transport, possibly by
C. F. Higgins; J. W. Payne
The rice Osmyb4 gene enhances tolerance to frost and improves germination under unfavourable conditions in transgenic barley plants.
The Osmyb4 rice gene, coding for a transcription factor, proved to be efficient against different abiotic stresses as a trans(cis)gene in several plant species, although the effectiveness was dependent on the host genomic background. Eight barley transgenic lines carrying the rice Osmyb4 gene under the control of the Arabidopsis cold inducible promoter cor15a were produced to test the efficiency of this gene in barley. After a preliminary test, the best performing lines were subjected to freezing at -11°C and -12°C. Frost tolerance was assessed measured the F(v)/F(m) parameter widely used to indicate the maximum quantum yield of photosystem II photochemistry in the dark adapted state. Three transgenic lines showed significantly increased tolerance. These selected lines were further studied under a complex stress applying cold and hypoxia at germinating stage. In these conditions the three selected transgenic lines outperformed the wild type barley in terms of germination vigour. The transgenic plants also showed a significant modification of their metabolism under cold/hypoxia conditions as demonstrated through the assessment of the activity of key enzymes involved in anoxic stress response. None of the transgenic lines showed dwarfism, just a slight retarded growth. These results provide evidence that the cold dependent expression of Osmyb4 can efficiently improved frost tolerance and germination vigour at low temperature without deleterious effect on plant growth. PMID:22246661
Soltész, Alexandra; Vágújfalvi, Attila; Rizza, Fulvia; Kerepesi, Ildikó; Galiba, Gábor; Cattivelli, Luigi; Coraggio, Immacolata; Crosatti, Cristina
The Role of ?-Glucosidase in Germinating Barley Grains1[W][OA
The importance of ?-glucosidase in the endosperm starch metabolism of barley (Hordeum vulgare) seedlings is poorly understood. The enzyme converts maltose to glucose (Glc), but in vitro studies indicate that it can also attack starch granules. To discover its role in vivo, we took complementary chemical-genetic and reverse-genetic approaches. We identified iminosugar inhibitors of a recombinant form of an ?-glucosidase previously discovered in barley endosperm (ALPHA-GLUCOSIDASE97 [HvAGL97]), and applied four of them to germinating grains. All four decreased the Glc-to-maltose ratio in the endosperm 10 d after imbibition, implying inhibition of maltase activity. Three of the four inhibitors also reduced starch degradation and seedling growth, but the fourth did not affect these parameters. Inhibition of starch degradation was apparently not due to inhibition of amylases. Inhibition of seedling growth was primarily a direct effect of the inhibitors on roots and coleoptiles rather than an indirect effect of the inhibition of endosperm metabolism. It may reflect inhibition of glycoprotein-processing glucosidases in these organs. In transgenic seedlings carrying an RNA interference silencing cassette for HvAgl97, ?-glucosidase activity was reduced by up to 50%. There was a large decrease in the Glc-to-maltose ratio in these lines but no effect on starch degradation or seedling growth. Our results suggest that the ?-glucosidase HvAGL97 is the major endosperm enzyme catalyzing the conversion of maltose to Glc but is not required for starch degradation. However, the effects of three glucosidase inhibitors on starch degradation in the endosperm indicate the existence of unidentified glucosidase(s) required for this process.
Stanley, Duncan; Rejzek, Martin; Naested, Henrik; Smedley, Mark; Otero, Sofia; Fahy, Brendan; Thorpe, Frazer; Nash, Robert J.; Harwood, Wendy; Svensson, Birte; Denyer, Kay; Field, Robert A.; Smith, Alison M.
Composition for accelerating seed germination and plant growth
US Patent & Trademark Office Database
Lipo Chitooligosaccharide (LCO) [NodBj-V(C18:1,Mefuc)] isolated from Bradyrhizobium japonicum strain 532C was able to stimulate seed germination/seedling emergence, or in the case of potato, sprouting, of a number of crop plants representing eight distantly related plant families (Poaceae, Fabaceae, Brassicaceae, Cucurbitaceac, Malvaceae, Asteraceae, Chenopodiaceae and Solanaceae) of plants, at 25 and/or at 15.degree. C. It also promoted sprouting potato minitubers. Other LCOs [NodRM-V(C.sub.16:2,5) and LCO from R. leguminosarum] were also shown to also display growth-promoting effects on the tested crop plants. The compositions comprising at least one LCO are shown to be effective in promoting growth under both laboratory and field conditions. The invention thus also relates to methods for promoting seed germination and/or seedling emergence and/or growth of plants comprising subjecting the seeds and/or plants to an effective amount of an agricultural composition comprising at least one LCO.
Seed germination ecology of the summer annual Cyperus squarrosus in an unpredictable mudflat habitat
The purpose of our study was to better understand seed germination ecology of the summer annual sedge Cyperus squarrosus, which grows in various habitats, including mudflats and shallow soil over limestone bedrock (rock outcrops), where timing of the period favorable for germination and completion of the life cycle is unpredictable. Over a 28.5-month period, temperature and light:dark requirements for germination were determined at monthly intervals for seeds collected from mudflats and buried under flooded and under nonflooded conditions at natural temperature regimes. Data on dormancy and germination were compared to those published for seeds collected from plants growing on rock outcrops. Under both flooded and nonflooded conditions, seeds from mudflats exhibited an annual conditional dormancy/nondormancy cycle, similar to those from rock outcrops buried under nonflooded conditions. Seeds from mudflats germinated to higher percentages at mid-summer temperatures (35/20 °C) in mid-summer than those from rock outcrops. On the other hand, seeds from rock outcrops germinated to higher percentages at March temperatures (15/6 °C) in March than those from mudflats. Thus, seeds could germinate on mudflats any time from April through September if dewatering occurred, and they could germinate on rock outcrops any time from March through June and in September if soil moisture was nonlimiting; in both habitats light would be required for germination. Since seeds on mudflats may be flooded for several consecutive years, mudflats are more unpredictable than rock outcrops. Ability of seeds from mudflats to germinate to high percentages in light at 35/20 °C throughout the summer and those from rock outcrops not to do so may be related to the greater unpredictability of the mudflat. Each year for 11 years, seeds germinated in mudflat soil samples kept in a nonheated greenhouse, reaching a total of 22526 ± 1401 (mean ± S.E.) seeds m -2; thus, the species has the potential to form a large long-lived persistent soil seed bank.
Baskin, Carol C.; Baskin, Jerry M.; Chester, Edward W.
Seed production, pre-dispersal seed predation and germination of Nothofagus glauca (Nothofagaceae) in a temperate fragmented forest in Chile
The ecological processes and interactions that involve plants at the seed level may be altered in a fragmented forest, with consequences on plant recruitment and forest structure. We studied seed production, pre-dispersal seed predation and germination of non-damaged and damaged seeds of the endemic and vulnerable Nothofagus glauca tree, in small fragments and in a continuous area of the Maulino
Aracely Burgos; Audrey A. Grez; Ramiro O. Bustamante
Seed Germination of GA-Insensitive sleepy1 Mutants Does Not Require RGL2 Protein Disappearance in Arabidopsis[W
We explore the roles of gibberellin (GA) signaling genes SLEEPY1 (SLY1) and RGA-LIKE2 (RGL2) in regulation of seed germination in Arabidopsis thaliana, a plant in which the hormone GA is required for seed germination. Seed germination failure in the GA biosynthesis mutant ga1-3 is rescued by GA and by mutations in the DELLA gene RGL2, suggesting that RGL2 represses seed germination. RGL2 protein disappears before wild-type seed germination, consistent with the model that GA stimulates germination by causing the SCFSLY1 E3 ubiquitin ligase complex to trigger ubiquitination and destruction of RGL2. Unlike ga1-3, the GA-insensitive sly1 mutants show variable seed dormancy. Seed lots with high seed dormancy after-ripened slowly, with stronger alleles requiring more time. We expected that if RGL2 negatively controls seed germination, sly1 mutant seeds that germinate well should accumulate lower RGL2 levels than those failing to germinate. Surprisingly, RGL2 accumulated at high levels even in after-ripened sly1 mutant seeds with 100% germination, suggesting that RGL2 disappearance is not a prerequisite for seed germination in the sly1 background. Without GA, several GA-induced genes show increased accumulation in sly1 seeds compared with ga1-3. It is possible that the RGL2 repressor of seed germination is inactivated by after-ripening of sly1 mutant seeds.
Ariizumi, Tohru; Steber, Camille M.
G Protein Signaling in the Regulation of Rice Seed Germination
NSDL National Science Digital Library
Seed germination and early seedling growth are regulated by an intricate network of hormonal signaling pathways. The plant hormones gibberellic acid (GA) and abscisic acid (ABA) are particularly important positive and negative regulators of these processes, respectively. In the cereal rice, mutant analysis has implicated heterotrimeric guanine nucleotide–binding protein (G protein) signaling in GA-stimulated expression of several genes, including expression of the gene encoding the hydrolytic enzyme α-amylase, which breaks down carbohydrate reserves and thus mobilizes nutrients that nourish the young seedling.
Sarah M. Assmann (Penn State University;Biology Department REV)
Quantitative trait loci analysis for rice seed vigor during the germination stage*
Seed vigor is an important characteristic of seed quality, and rice cultivars with strong seed vigor are desirable in direct-sowing rice production for optimum stand establishment. In the present study, the quantitative trait loci (QTLs) of three traits for rice seed vigor during the germination stage, including germination rate, final germination percentage, and germination index, were investigated using one recombinant inbred line (RIL) population derived from a cross between japonica Daguandao and indica IR28, and using the multiple interval mapping (MIM) approach. The results show that indica rice presented stronger seed vigor during the germination stage than japonica rice. A total of ten QTLs, and at least five novel alleles, were detected to control rice seed vigor, and the amount of variation (R 2) explained by an individual QTL ranged from 7.5% to 68.5%, with three major QTLs with R 2>20%. Most of the QTLs detected here are likely to coincide with QTLs for seed weight, seed size, or seed dormancy, suggesting that the rice seed vigor might be correlated with seed weight, seed size, and seed dormancy. At least five QTLs are novel alleles with no previous reports of seed vigor genes in rice, and those major or minor QTLs could be used to significantly improve the seed vigor by marker-assisted selection (MAS) in rice.
Wang, Zhou-fei; Wang, Jian-fei; Bao, Yong-mei; Wang, Fu-hua; Zhang, Hong-sheng
3,4-Dihydroxybenzaldehyde purified from the barley seeds ( Hordeum vulgare) inhibits oxidative DNA damage and apoptosis via its antioxidant activity
Barley is a major crop worldwide. It has been reported that barley seeds have an effect on scavenging ROS. However, little has been known about the functional role of the barley on the inhibition of DNA damage and apoptosis by ROS. In this study, we purified 3,4-dihydroxybenzaldehyde from the barley with silica gel column chromatography and HPLC and then identified
Jin Boo Jeong; Se Chul Hong; Hyung Jin Jeong
Interaction Effects of Seed Mass and Temperature on Germination in Australian Species of Frankenia (Frankeniaceae)
The seed size and number theories have been proposed to explain the advantages of having many small versus a few large seeds\\u000a in plants. In particular, seed germination is predicted to be shaped by temperature, and may differ for small and large seeds.\\u000a In this study, we experimentally test germination at different temperatures in 12 species of arid zone plants
Lyndlee C. Easton; Sonia Kleindorfer
Seed germination and seedling development of Prunus armeniaca under different burial depths in soil
A semi-greenhouse study was conducted to understand the effects of soil burial depth on seed germination and seedling development.\\u000a The seeds of wild apricot (Prunus armeniaca) were buried at the soil depths of 0-cm, 4-cm, 8-cm, and 12-cm, respectively, to simulate the seed hoarding behavior of rodents\\u000a in the field. The results revealed that the rates of seed germination and
GUO Cai-ruWANG; Zhen-long Wang; Ji-qi Lu
Does Germination Success Differ with Respect to Seed Mass and Germination Season? Experimental Testing of Plant Functional Trait Responses to Grassland Management
Background and Aims Plant functional trait responses to processes such as grassland management have been analysed frequently; however, the scaling-up from individual traits to the outcomes of vegetation dynamics has seldom been tested. In this experiment, germination success was studied with respect to the relationships between grassland management (mowing and grazing), as well as abandonment, and two traits that are relevant for seedling recruitment: seed mass and germination season. On the basis of discussions in the literature and indirect trait analyses in our previous studies, the following hypotheses are proposed: (1) with respect to seed mass, mowing and grazing favour the germination of small seeds, whereas after abandonment the germination success of larger seeds is higher; and (2) with respect to germination season, mowing and grazing favour autumn-germinating seeds, whereas succession promotes spring-germinating seeds. Methods The germination experiment took place in a semi-natural, dry grassland in north-east Germany. Seeds of eight herbaceous species that differ with respect to seed mass and germination season were sown in mown, grazed and abandoned plots. Germination success was documented during the following year. Key Results and Conclusions Contrary to the hypothesis, germination of small seeds was not promoted by mowing or grazing and they germinated relatively more often than expected in the abandoned plots. A relationship between abandonment and gaps of bare soil below the vegetation cover that favour germination of small seeds was likely, but could not be proved statistically. It is possible that the small seeds suffered less from predation. Mowing favoured autumn germination, which could be explained by the removal of biomass in late summer. Contrary to our expectation, there was relatively more spring germination after grazing than after mowing, yet vegetation height was smallest in spring. Generally, germination season was found to be related to the temporal occurrence of favourable light conditions.
Kahmen, S.; Poschlod, P.
Influence of light, temperature, salinity and storage on seed germination of Haloxylon ammodendron
Haloxylon ammodendron is a shrubby perennial distributed in many sandy and saline areas of deserts of Northwest China. It is an important economic plant used for sand fixation, pasture and fuel. Seed germination is the critical stage for species survival. The optimal temperature for germination is 10°C and germination was the lowest at 30°C in light and darkness. The higher
Zhenying Huang; Xinshi Zhang; Guanghua Zheng; Yitzchak Gutterman
The role of water channel proteins and nitric oxide signaling in rice seed germination
Previous studies have demonstrated the possible role of several aquaporins in seed germination. But systematic investigation of the role of aquaporin family members in this process is lacking. Here, the developmental regulation of plasma membrane intrinsic protein (PIP) expression throughout germination and post-germination processes in rice embryos was analyzed. The expression patterns of the PIPs suggest these aquaporins play different
Hong-Yan Liu; Xin Yu; Da-Yong Cui; Mei-Hao Sun; Wei-Ning Sun; Zhang-Cheng Tang; Sang-Soo Kwak; Wei-Ai Su
The Changes of ?-Galactosides during Germination and High Pressure Treatment of Legume Seeds
The ?-galactosides negatively affect of grain legumes digestibility. The most effective way of ?-galactosides content decreasing is germination. The contents of ?-galactosides in legume seeds were decreased by germination up to 16% of original value (lentil). During the germination, the contents of microorganisms are arising to high values. The effective method for decreasing of microorganisms content is high pressure treatment.
J. DoStálo Vá; P. KaDleC; J. Bernáš; M. Houš Ka; J. Stro
Factors influencing seed germination of medicinal plant Salvia aegyptiaca L. (Lamiaceae)
Salvia aegyptiaca is a xerophytic perennial herb belongs to the Lamiaceae family commonly used for medicinal purposes. Laboratory experiments were carried out to assess the effects of temperature and salinity on seed germination and recovery responses after transferring to distilled water. Temperatures between 10 and 40°C seem to be favourable for the germination of this species. Germination was inhibited by
Mustapha Gorai; Hayet Gasmi; Mohamed Neffati
Effect of distillery effluent on seed germination in some vegetable crops
A laboratory experiment was conducted to study the effect of different concentrations (0%, 5%, 10%, 15%, 20%, 25%, 50%, 75% and 100%) of distillery effluent (raw spent wash) on seed germination (%), speed of germination, peak value and germination value in some vegetable crops: tomato, chilli, bottle gourd, cucumber and onion. The distillery effluent did not show any inhibitory effect
S Ramana; A. K Biswas; S Kundu; J. K Saha; R. B. R Yadava
Production of Strigolactones by Arabidopsis thaliana responsible for Orobanche aegyptiaca seed germination
The germination stimulants produced by Arabidopsis thaliana, a host of root parasitic plants Orobanche spp. but not of arbuscular mycorrhizal (AM) fungi were examined. Root exudates from the hydroponically grown A. thaliana plants were subjected to reverse phase high performance liquid chromatography (HPLC) and retention times of germination stimulants\\u000a inducing O. aegyptiaca seed germination were compared with those of strigolactone
Yaakov Goldwasser; Kaori Yoneyama; Xiaonan Xie; Koichi Yoneyama
A Race for Survival: Can Bromus tectorum Seeds Escape Pyrenophora semeniperda-caused Mortality by Germinating Quickly?
Background and Aims Pathogen–seed interactions may involve a race for seed resources, so that seeds that germinate more quickly, mobilizing reserves, will be more likely to escape seed death than slow-germinating seeds. This race-for-survival hypothesis was tested for the North American seed pathogen Pyrenophora semeniperda on seeds of the annual grass Bromus tectorum, an invasive plant in North America. In this species, the seed germination rate varies as a function of dormancy status; dormant seeds germinate slowly if at all, whereas non-dormant seeds germinate quickly. Methods Three experimental approaches were utilized: (a) artificial inoculations of mature seeds that varied in primary dormancy status and wounding treatment; (b) naturally inoculated undispersed seeds that varied in primary dormancy status; and (c) naturally inoculated seeds from the carry-over seed bank that varied in degree of secondary dormancy, habitat of origin and seed age. Key Results In all three approaches, seeds that germinated slowly were usually killed by the pathogen, whereas seeds that germinated quickly frequently escaped. Pyrenophora semeniperda reduced B. tectorum seed banks. Populations in drier habitats sustained 50 times more seed mortality than a population in a mesic habitat. Older carry-over seeds experienced 30 % more mortality than younger seeds. Conclusions Given the dramatic levels of seed death and the ability of this pathogen to reduce seed carry-over, it is intriguing to consider whether P. semeniperda could be used to control B. tectorum through direct reduction of its seed bank.
Beckstead, Julie; Meyer, Susan E.; Molder, Cherrilyn J.; Smith, Caitlyn
[Effect of seed soaking with aluminum on seed germination and seedling physiology of Platycodon grandiflorum].
In order to study the effect of seed soaking with different aluminum solution on seed germination and seedling physiological characteristics of Platycondon grandiflorum, two P. grandiflorum varieties'seed (the white flower and the purple flower) were soaked in Al3+ solution with different concentrations (0, 10, 100, 250, 500, 750 and 1000 mg x L) for 24 h, then germinated in illumination incubator. Results showed that the aluminum toxicity on the trends of the germination rate, germination index and vigor index was positive associated with its concentration, and the Al tolerance of the purple was slightly greater than that of the white. There were some relationships between the physiological indices, which were the leakage rate of electrolyte, the malonaldehyde (MDA) content, the activities of peroxidase (POD) and superoxide dismutase (SOD) , the free praline(Pro) and the soluble sugar contents, with the concentrations of Al. It was suggested that there was Al tolerance difference between the two P. grandiflorum varieties: the purple flower was greater than the white. PMID:21438384
Zhu, Lixiang; Wang, Jianhua; Fang, Xinsheng; Wang, Yong; Hao, Junkai; Weiwei, Ma; Jiao, Tianying
Effects of methylglyoxal- bis (guanylhydrazone) and abscisic acid on polyamine metabolism in embryonectomized barley seeds
Incorporation of L-[U-14C] arginine or L-[U-14C] ornithine into putrescine (Put), spermidine (Spd) and spermine (Spm) in embryonectomized barley seeds (Hordeum vulgare L. cv. Himalaya) was studied following imbition with methylglyoxal-bis (guanylhydrazone) (MGBG) and abscisic acid (ABA). Both radiolabeled amino acids were incorporated into the amines as a result of active polyamine biosynthesis in the seed during imbibition. In the aleurone
Paul P. C. Lin
Spatial and Temporal Divergence of Expression in Duplicated Barley Germin-Like Protein-Encoding Genes
Subfunctionalization is the process by which a pair of duplicated genes, or paralogs, experiences a reduction of individual expression patterns or function while still reproducing the complete expression pattern and function of the ancestral gene. Two germin-like protein (GLP)-encoding genes, GerB and GerF, are paralogs that belong to a small gene family in barley (Hordeum vulgare). Both genes share high nucleotide sequence similarity in coding and noncoding regions and encode identical apoplastic proteins. The use of RNA gel blots, coupled with single-stranded conformation polymorphism (SSCP) analysis of RT–PCR products, elucidated the developmental and tissue-specific expression patterns of each gene. Individual expression patterns provided evidence of both overlapping redundancy and early subfunctionalization. GerB is predominantly expressed in developing shoots, while GerF is predominantly expressed in seedling roots, developing spikes, and pericarp/testa. GerF promoter deletion studies located a region (?356/?97) responsible for high promoter activity and showed the ability of GerB and GerF upstream regions to drive gfp expression in coleoptiles, epicarps, and lemma/palea of developing spikes. The observed expression patterns are consistent with proposed roles in plant development and defense mechanisms for this gene family. These roles may explain why redundancy has been selectively maintained in this duplicate gene pair.
Federico, Maria L.; Iniguez-Luy, Federico L.; Skadsen, Ronald W.; Kaeppler, Heidi F.
Ethylene-, light-, and prechill-enhanced germination of Echinacea angustifolia seeds
Echinacea angustifolia DC., the common coneflower of the western Great Plains, is difficult to propagate by achenes due to inherent seed dormancy. The effects of light and prechilling on seed germination were examined, alone and combined with scarification (mechanical, acid) and ethylene (ethephon) treatments. The results showed that a 2-week prechill treatment combined with ethephon and continuous light, followed by a 2-week germination period in light (16 hours per day) at 25 C, could induce >95% seed germination in E. angustifolia. This was a significantly higher percentage of germination over a shorter period of time than any other method examined or previously described. This treatment also synchronized germination, with most viable seeds germinating in <1 week after being placed at 25 C in the light. Chemical name used: 2-chloroethylphosphonic acid (ethephon).
Feghahati, S.M.J.; Reese, R.N. (South Dakota State Univ., Brookings, SD (United States). Dept. of Biology and Microbiology)
Structural requirements of strigolactones for germination induction of Striga gesnerioides seeds.
Strigolactones are highly potent germination stimulants for seeds of the parasitic weeds Striga and Orobanche spp. 4-Hydroxy-GR24 and 4-acetoxy-GR24 were prepared and their abilities to induce seed germination of Striga gesnerioides evaluated. Optically active (8bR,2'R)-isomers induced germination, although the racemic diastereomers were inactive. In contrast, the stereoisomer of GR24 with the same configuration induced negligible germination. Some stereoisomers of GR24 and its analogues acted as effective antagonists for induction of seed germination by cowpea root exudates. These results suggest that both an oxygenated substituent at C-4 and the configuration of the tricyclic lactone and the D-ring are essential structural requirements for induction of germination in S. gesnerioides seeds. PMID:21819156
Ueno, Kotomi; Fujiwara, Mami; Nomura, Saki; Mizutani, Masaharu; Sasaki, Mitsuru; Takikawa, Hirosato; Sugimoto, Yukihiro
Essential role of urease in germination of nitrogen-limited Arabidopsis thaliana seeds
In Arabidopsis thaliana, urease transcript levels increased sharply between 2 and 4 d after germination (DAC) and were maintained at maximal levels until at least 8 DAC. Seed urease specific activity declined upon germination but began to increase in seedlings 2 DAC, reaching approximately 75% of seed activity by 8 DAC. Urea levels showed a small transient increase 1 DAC
Laura E. Zonia; Norm E. Stebbins; Joseph Carmine Polacco
Effect of carbofuran on seed germination and initial development of seven crops
The effect of carbofuran on the germination percentage, germination rate, and initial development of seedlings of caraway, fenugreek, wheat, sugar beet, sunflower, vetch and chickpea was studied in the laboratory. Seeds were treated with Curaterr 5GR - a 5% granular formulation, and with a 30% liquid concentrate of carbofuran. Treatment doses ranged from 0.5 to 80 mg a.i. per seed,
L. Benjamini
Levels of physiological dormancy and methods for improving seed germination of four rose species
Low seed germination is a major problem in commercial rose propagation and breeding and is species-dependent. The present work selected four rose species previously un-examined to explore effective methods for improving seed germination and the relevant dormancy mechanism and its levels in seven experiments. The results showed that both pulp and achenes from the four rose shrubs had chemical substances
Zhiqiong Zhou; Weikai Bao
Measuring Effects of Music, Noise, and Healing Energy Using a Seed Germination Bioassay
Objective: To measure biologic effects of music, noise, and healing energy without human preferences or placebo effects using seed germination as an objective biomarker. Methods: A series of five experiments were performed utilizing okra and zucchini seeds germinated in acoustically shielded, thermally insulated, dark, humid growth chambers. Conditions compared were an un- treated control, musical sound, pink noise, and healing
Katherine Creath; Gary E. Schwartz
Seed germination of woody legumes from deciduous tropical forest of southern Mexico
Seed germination experiments were conducted on six woody leguminous species which are widely used by rural inhabitants of a mountainous tropical subhumid region in southern Mexico. Conditions for optimum germination were sought in nursery conditions by applying various hot water treatments (1 min, 3 min, 5 min and 10 min in boiling water) and scarification to seeds of differing storage
Virginia Cervantes; Julia Carabias; Carlos Vázquez-Yanes
Crude extract of Astragalus mongholicus root inhibits crop seed germination and soil nitrifying activity
Astragalus mongholicus has been of medicinal use within the traditional Chinese system for centuries. However, little information is available on its allelopathic effects on other crop plants and soil biochemical properties. Field experiment showed that the extracted residues of A. mongholicus root inhibited seed germination of wheat. Inhibition of seed germination was further confirmed in laboratory using the same crude
Jian Mao; Linzhang Yang; Yuming Shi; Jian Hu; Zhe Piao; Lijuan Mei; Shixue Yin
EFFECTS OF ALUMINIUM (Al 3+ ) ON SEED GERMINATION AND SEEDLING GROWTH OF WHEAT (TRITICUM AESTIVUM L.)
Effects of different concentrations of aluminium (Al 3+ ) on seed germination of high yielding varieties of wheat (Triticum aestivum L.) were investigated. Al 3+ at 500 ppm had inhibitory effect on seed germination, seedling growth and its dry matter. Relatively higher root and shoot dry matter in Sonlika, Fang-60 and lower in Baw-923 and Protiva were found. Root growth
A structural study of germination in celery ( Apium graveolens L.) seed with emphasis on endosperm breakdown
Germination of celery seed occurred after 6 d of imbibition in light. During this time the embryo enlarged at the expense of the adjacent endosperm cells and at the time of germination was 2–3 times as long as in the dry seed. Breakdown of the endosperm cells near the root cap preceeded radicle emergence. None of these changes occurred in
J. V. Jacobsen; E. Pressman
EPA Science Inventory
Seed germination tests measure soil toxicity directly, while root elongation tests consider the indirect effects of water-soluble constituents which may be present in site-samples. n the seed germination toxicity test, site-soil is mixed with a reference soil to yield exposure co...
Effect of heavy metals on germination of seeds
With the expansion of the world population, the environmental pollution and toxicity by chemicals raises concern. Rapid industrialization and urbanization processes has led to the incorporation of pollutants such as pesticides, petroleum products, acids and heavy metals in the natural resources like soil, water and air thus degrading not only the quality of the environment, but also affecting both plants and animals. Heavy metals including lead, nickel, cadmium, copper, cobalt, chromium and mercury are important environmental pollutants that cause toxic effects to plants; thus, lessening productivity and posing dangerous threats to the agro-ecosystems. They act as stress to plants and affect the plant physiology. In this review, we have summarized the effects of heavy metals on seeds of different plants affecting the germination process. Although reports exist on mechanisms by which the heavy metals act as stress and how plants have learnt to overcome, the future scope of this review remains in excavating the signaling mechanisms in germinating seeds in response to heavy metal stress.
Sethy, Sunil Kumar; Ghosh, Shyamasree
Effect of straw extract on water absorption and germination of wheat ( Triticum aestivum L. variety RR21) seeds
Summary Freshly prepared straw extract inhibited wheat seed germination by about 18 per cent but did not affect water absorption by germinating wheat seeds. The maximum germination inhibition (47 per cent) was noticed with extract of straw rotted for 15 days. The germination inhibitory effect of rotting straw was over at 31 days of straw rotting.
P. C. Srivastava; N. G. Totey; Om Prakash
Effect of passage through duck gut on germination of fennel pondweed seeds
Vertebrates are important seed dispersers for many plants. In addition to transport of seeds, ingestion often affects the proportion or rate of seed germination. We present one of the first studies comparing the effects of different waterbird species on the seeds of a subcosmopolitan pondweed, Potamogeton pectinatus. We also present the first comparison of the effects of digestion by ducks
Luis Santamaría; Iris Charalambidou; Jordi Figuerola; Andy J. Green
Postdispersal Removal and Germination of Seed Dispersed by Cercopithecus nictitans in a West African Montane Forest
Factors that determine the effectiveness of primates as seed dispersers include (i) the microsite into which they deposit seed, (ii) secondary removal of seed by other taxa and (iii) the effect of gut passage and\\/or spitting on subsequent seed germination. This contribution evaluated these factors in the little studied putty-nosed monkey, Cercopithecus nictitans, in a Nigerian montane forest. Field experiments
Hazel M. Chapman; Stephen L. Goldson; Josie Beck
Analysis of directional root growth patterns from corn and soybean seeds germinated in space
The JOSE (JASON Outreach Seed Experiment) payload was the first plant experiment conducted on the International Space Station (ISS). It consisted of having an on-orbit watering of eight transparent seed pouches each of which contained 6 individual seeds of either soybean (Glycine max cv McCall) or corn ( Zea mays ). The seeds were glued to a germination paper substrate
H. Levine; G. Tynes; K. Norwood
Characteristics of seed germination in five non-halophytic Chinese desert shrub species
The effects of temperature, NaCl, and polyethylene glycol (PEG)-6000 on the seed germination of five non-halophytic Chinese desert shrub species were investigated. The minimum temperature of germination was 10°C for all species, and the maximum temperature varied among species from 25 to 35°C. Isotonic solutions of NaCl and PEG caused different effects on seed germination in all five species. When
Kazuo Tobe; Liping Zhang; Guoyu Yu Qiu; Hideyuki Shimizu; Kenji Omasa
Textile Effluents Affected Seed Germination and Early Growth of Some Winter Vegetable Crops: A Case Study
In order to assess as to whether treated textile effluent could be safely used to irrigate some winter vegetables, growth\\u000a room experiments were conducted. Varying levels of treated and untreated textile effluents were applied to germinating seeds\\u000a of some winter vegetables and their effect was evaluated on germination and early growth stage using seed germination, growth,\\u000a and biochemical attributes. From
Abida Rehman; Haq Nawaz Bhatti; Habib-ur-Rehman Athar
Phytochrome Regulation and Differential Expression of Gibberellin 3Hydroxylase Genes in Germinating Arabidopsis Seeds
Despite extensive studies on the roles of phytochrome in photostimulated seed germination, the mechanisms downstream of the photoreceptor that promote germination are largely unknown. Previous studies have indicated that light-induced germination of Arabidopsis seeds is mediated by the hormone gibberellin (GA). Using RNA gel blot analyses, we studied the regulation of two Arabidopsis genes, GA4 and GA4H (for GA4 homolog),
Shinjiro Yamaguchi; Maria W. Smith; Robert G. S. Brown; Yuji Kamiya; Tai-ping Sun
Effects of stress temperatures of germination on polyamine titers of soybean seeds
High and low stress temperatures during seed germination and seedling development limit total germination and the rate of germination and growth. Changes in polyamine (PA) concentrations in seeds of different species have been associated with germination, growth and environmental stresses such as temperature, drought, oxygen, chilling injury and osmotic conditions. Two studies were conducted to determine the effect of stress temperatures during germination and seedling development on polyamine titers in soybean seeds. Three germination temperatures, 25, 30, and 36°C were used in the first study to evaluate their influence on changes in polyamine concentrations in soybean seeds germinated at 76 and 90 hours. The polyamines (PAs), cadaverine (Cad), putrescine (Put), spermidine (Spd), agmatine (Agm), and spermine (Spin) were quantified by HPLC using a cation exchange column and an electrochemical detector. Cad, Put, Agm, and Spd declined as the germination temperatures increased from 25 to 36°C. Conversely, Spin increased considerably with an increase in temperature. Total germination was reduced from 97.2 to 92.5% as germination temperatures increased from 25 to 36°C. Germination time did not affect Cad, Agm and Spm, and total germination, however, the interaction between temperature and germination time for Put and Spd concentrations was significant. In the second study, changes in PA concentrations, seedling growth, germination time (t50), fresh and dry weight, and moisture content were measured in the embryonic axis and cotyledons of soybean seeds germinated at 10 and 25°C through six stages of germination dry seed (DS), testa split (TS), radicle at 10 mm (Ra-10), root hairs visible (RHV), secondary root primordia (SRP), and complete seedling (CS). The concentrations of Cad and Put in the embryonic axis, were significantly higher in seeds germinated under low temperature than in seeds at 25°C (approximately 10 and 3 fold respectively). However, this difference was not observed until the last three stages of germination. The stage of germination also influenced the levels of these polyamines. The concentrations of Cad and Put detected at the CS stage were 50 and 18 fold respectively, relative to the initial concentrations found at the DS stage. Spd levels in seeds under stress temperatures also increased, but to a lesser extent compared to Cad and Put. Differences in Spd concentrations between temperatures were observed only at the CS stage. Agm concentrations were higher at 25 than at 10°C at SRP and CS. Spm concentrations of seeds germinated at 25°C remained higher during the first four stages of development but at the end of germination, seeds at 10°C had higher quantities of Spm. In the cotyledons, Polyamines tended to decline with stages of germination, regardless of the temperature. However, Agm levels increased in the cotyledons of soybean seeds. Maximum dry weight and seedling growth was found at RHV, SRP, and CS. Maximum levels of Cad and Put were also found during these stages. Spd increased with both temperatures from DS to Ra-10, thereafter, Spd levels in seeds at 10°C continued increasing while seeds at 25°C declined. High and low stress germination temperatures caused significant changes in polyamine concentrations, reduced germination and seedling growth of soybean seeds.
Pineda-Mejia, Renan
Effects of cold stratification on germination rate and percentage of caper (Capparis ovata Desf.) seeds.
Caper is an important plant because of its high adaptability to marginal agriculture fields that are not suitable for agricultural crops. Different parts of caper such as roots, fruits, flowers and buds can be used to increase the inhabitant's income. The goal of this research is to determine germination rate and percentage of caper according to different duration of cold stratification (10, 20, 30, 40, 50 and 60 days) treatments. Cold stratification procedures under greenhouse condition were applied for eliminating seed dormancy to find the most suitable germination conditions because the presence of seed dormancy causes difficulties in seedling production. The seed germination started and stopped 21 and 57 days after sowing, respectively. While the highest germination percentage (46.6%) was obtained in seeds that were cold stratified for 60 days, the lowest germination percentage (3.6 7%) was determined in control seeds. PMID:17405328
Olmez, Zafer; Gokturk, Askin; Gulcu, Suleyman
Examining the interaction of light, nutrients and carbohydrates on seed germination and early seedling development of Bletia purpurea (Orchidaceae)
The effects of carbohydrate availability, carbohydrate source, nutrient availability and illumination on germination and early\\u000a development of Bletia purpurea (Orchidaceae) seeds were investigated using asymbiotic seed germination. Of special interest was determining the minimum\\u000a nutritional and light requirements for the completion of germination. Germination and development was limited when seeds were\\u000a cultured in darkness without sucrose. Seeds were able to
Timothy R. Johnson; Michael E. Kane; Hector E. Pérez
Effect of salts (Na2SO4, Na2CO3, MgSO4, NaCl, MgCl2), soil extract and polyethylene glycol (PEG-6000) on the germination of Chenopodium glaucum L., seed was studied. Maximum germination was obtained in distilled water. Germination decreased with increase in salinity. The inhibition of germination by salt solutions was in the order of MgCl2 > Na2SO4 > Na2CO3 > NaCl > Soil extract >
Barley ?-amylase bound to its endogenous protein inhibitor BASI: crystal structure of the complex at 1.9 ĺ resolution
Background: Barley ?-amylase is a 45 kDa enzyme which is involved in starch degradation during barley seed germination. The released sugars provide the plant embryo with energy for growth. The major barley ?-amylase isozyme (AMY2) binds with high affinity to the endogenous inhibitor BASI (barley ?-amylase\\/subtilisin inhibitor) whereas the minor isozyme (AMY1) is not inhibited. BASI is a 19.6 kDa
François Vallée; Anders Kadziola; Yves Bourne; Michel Juy; Kees W Rodenburg; Birte Svensson; Richard Haser
Influence of Salicylic Acid on Stress Tolerance During Seed Germination of Triticum aestivum and Hordeum vulgare
The relationship between compatible solutes (osmolytes) and antioxidants are the strategies that plants have developed to tolerate salt stress. Pre-treatment of wheat (Triticum aestivum L. cv) and barley (Hordeum vulgare L. cv) with Salicylic acid (SA) can be enhanced their tolerance to saline stress during germination. The alleviation of oxidative damage and increased resistance to salt stress induced by 150
Hanan E. Deef
Seed germination responses of Periploca sepium Bunge, a dominant shrub in the Loess hilly regions of China
Experiments were conducted to determine the effects of temperature, light, osmotic stress, hydration-dehydration regime and stress relief on the seed germination of Periploca sepium Bunge (Chinese silk vine Asclepiadaceae), which is a native shrub in the Loess Plateau of Northwest China. Freshly harvested seeds germinated equally well in both light and darkness. Seeds germinated under all of tested temperature regimes,
Y. Y. An; Z. S. Liang; Y. Zhang
The promotive effect of smoke derived from burnt native vegetation on seed germination of Western Australian plants
Exposure of dormant seed to cold smoke derived from burnt native vegetation had a positive influence on germination in one or more seed provenances in 45 out of 94 species of native Western Australian plants that are normally hard to germinate. When tested under controlled conditions some species showed earlier germination in smoke treatments than controls; in others smoke-treated seeds
Kingsley W. Dixon; Shauna Roche; John S. Pate
[Effect of acid rain on seed germination of rice, wheat and rape].
Rice, wheat and rape seeds were treated with simulated acid rain at pH 2.0, 2.5, 3.0, 3.5, 4.0 and 5.0 levels for 7 days in order to understand the effects of acid rain on seed germination of various acid-fast plant. The germination test showed that seed germination was absolutely inhibited at pH 2.0 for three species. Rice and wheat seeds germinated abnormally at pH 2.5. WhenpH values above 3.0, percentage germination, germination energy, germination index, vigor index of rice, wheat and rape seeds increased in relation with decreased acidity levels. In contrast, the percentage of abnormal germination of rice and wheat decreased. The experiment data about physiological aspect demonstrated that water absorption rate, respiratory rate and storage reserve transformation rate of rice, wheat and rape seeds also increased with increased pH values. The storage loss of rice and wheat increased with increased pH values but that of rape decreased. Inhibition index of shoot and root length of three kinds of seeds decreased in relation with increased pH values. The amplitude difference of index of rice was lower than that of wheat, and wheat was lower than that of rape. The experiment data showed that rice had stronger fastness than wheat and rape, wheat had stronger fastness than rape under acid rain stress. PMID:15859434
Zeng, Qing-ling; Huang, Xiao-hua; Zhou, Qing
Germination Responses to Water Potential in Neotropical Pioneers Suggest Large-seeded Species Take More Risks
Background and Aims In neotropical forests, very small-seeded pioneer species (<0·1 mg seed mass) recruit preferentially in small tree fall gaps and at gap edges, but large-seeded pioneers do not. Since water availability is related to gap size, these differences in microsite preference may reflect in part species-specific differences in germination at reduced water potentials. Methods For 14 neotropical pioneer species, the hypothesis is tested that small-seeded species, with shallow initial rooting depths, reduce the risks associated with desiccation by germinating more slowly and at higher water potentials than large-seeded species. Key Results Germination occurred both more quickly and at lower water potentials with increasing seed mass. For example, Ochroma pyramidale (seed mass 5·5 mg) had a time to 50 % germination (T50) of 2·8 d and a median base potential for germination (?b50) of ?1·8 MPa while Clidemia quinquenervia (seed mass 0·017 mg) had a T50 of 17·6 d and ?b50 of ?1·1 MPa. Conclusions These data suggest that small-seeded species germinate only in comparatively moist microsites, such as small canopy gaps, which may reduce the risk of drought-induced mortality. Conversely, large-seeded species are able to germinate in the drier environment of large gaps, where they benefit by enhanced seedling growth in a high irradiance environment. The positive association of seed size and canopy gap size for optimal seedling establishment is maintained by differential germination responses to soil water availability coupled with the scaling of radicle growth rate and seed size, which collectively confer greater drought tolerance on large-seeded species.
Daws, Matthew I.; Crabtree, Lora M.; Dalling, James W.; Mullins, Christopher E.; Burslem, David F. R. P.
A high-throughput seed germination assay for root parasitic plants
Background Some root-parasitic plants belonging to the Orobanche, Phelipanche or Striga genus represent one of the most destructive and intractable weed problems to agricultural production in both developed and developing countries. Compared with most of the other weeds, parasitic weeds are difficult to control by conventional methods because of their life style. The main difficulties that currently limit the development of successful control methods are the ability of the parasite to produce a tremendous number of tiny seeds that may remain viable in the soil for more than 15 years. Seed germination requires induction by stimulants present in root exudates of host plants. Researches performed on these minute seeds are until now tedious and time-consuming because germination rate is usually evaluated in Petri-dish by counting germinated seeds under a binocular microscope. Results We developed an easy and fast method for germination rate determination based on a standardized 96-well plate test coupled with spectrophotometric reading of tetrazolium salt (MTT) reduction. We adapted the Mosmann's protocol for cell cultures to germinating seeds and determined the conditions of seed stimulation and germination, MTT staining and formazan salt solubilization required to obtain a linear relationship between absorbance and germination rate. Dose–response analyses were presented as applications of interest for assessing half maximal effective or inhibitory concentrations of germination stimulants (strigolactones) or inhibitors (ABA), respectively, using four parameter logistic curves. Conclusion The developed MTT system is simple and accurate. It yields reproducible results for germination bioassays of parasitic plant seeds. This method is adapted to high-throughput screenings of allelochemicals (stimulants, inhibitors) or biological extracts on parasitic plant seed germination, and strengthens the investigations of distinctive features of parasitic plant germination.
[Viability and germination characteristics of canopy-stored seeds of plants in sand dune area].
The study on the viability and germination characteristics of canopy-stored seeds remained in canopy until next May after maturation of 10 plants species in Horqin sandy land showed that more than 80% of the canopy-stored seeds of psammophytes such as Agriophyllum squarrosum, Artemisia wudanica and A. halodendron had viability, while less than 80% or even less than 30% of non-psammophytes seeds had viability. The canopy-stored seeds of psammophytes presented a rapid germination pattern. The canopy seed bank made the seed release of psammophytes postponed until the windy season ended and the rainy season started, when the seeds had high viability and could germinate rapidly. The canopy seed bank is one of ways for psammophytes to adapt drift sand and seasonal drought. PMID:18464627
Ma, Jun-Ling; Liu, Zhi-Min
Molecular Clustering Interrelationships and Carbohydrate Conformation in Hull and Seeds Among Barley Cultivars
The objective of this study was to use molecular spectral analyses with the diffuse reflectance Fourier transform infrared spectroscopy (DRIFT) bioanlytical technique to study carbohydrate conformation features, molecular clustering and interrelationships in hull and seed among six barley cultivars (AC Metcalfe, CDC Dolly, McLeod, CDC Helgason, CDC Trey, CDC Cowboy), which had different degradation kinetics in rumen. The molecular structure spectral analyses in both hull and seed involved the fingerprint regions of ca. 1536-1484 cm{sup -1} (attributed mainly to aromatic lignin semicircle ring stretch), ca. 1293-1212 cm{sup -1} (attributed mainly to cellulosic compounds in the hull), ca. 1269-1217 cm{sup -1} (attributed mainly to cellulosic compound in the seeds), and ca. 1180-800 cm{sup -1} (attributed mainly to total CHO C-O stretching vibrations) together with an agglomerative hierarchical cluster (AHCA) and principal component spectral analyses (PCA). The results showed that the DRIFT technique plus AHCA and PCA molecular analyses were able to reveal carbohydrate conformation features and identify carbohydrate molecular structure differences in both hull and seeds among the barley varieties. The carbohydrate molecular spectral analyses at the region of ca. 1185-800 cm{sup -1} together with the AHCA and PCA were able to show that the barley seed inherent structures exhibited distinguishable differences among the barley varieties. CDC Helgason had differences from AC Metcalfe, MeLeod, CDC Cowboy and CDC Dolly in carbohydrate conformation in the seed. Clear molecular cluster classes could be distinguished and identified in AHCA analysis and the separate ellipses could be grouped in PCA analysis. But CDC Helgason had no distinguished differences from CDC Trey in carbohydrate conformation. These carbohydrate conformation/structure difference could partially explain why the varieties were different in digestive behaviors in animals. The molecular spectroscopy technique used in this study could also be used for other plant-based feed and food structure studies.
N Liu; P Yu
Avian gut-passage effects on seed germination of shrubland species in Mediterranean central Chile
Effects of avian gut-passage on seed germination are important to assess the effectiveness of frugivores in woodland regeneration,\\u000a particularly in biodiversity hotspots that have a high incidence of avian frugivory. We examined the effect of avian gut-passage\\u000a on seed germination in contrast to seeds that remain uneaten in five shrub species in Mediterranean central Chile and sought\\u000a to determine the
Sharon ReidJuan; Juan J. Armesto
Gibberellins regulate seed germination in tomato by endosperm weakening: a study with gibberellin-deficient mutants
The germination of seeds of tomato [Lycopersicon esculentum (L.) Mill.] cv. Moneymaker has been compared with that of seeds of the gibberellin-deficient dwarf-mutant line ga-1, induced in the same genetic background. Germination of tomato seeds was absolutely dependent on the presence of either endogenous or exogenous gibberellins (GAs). Gibberellin A4+7 was 1000-fold more active than commercial gibberellic acid in inducing
S. P. C. Groot; C. M. Karssen
Phytochrome Control of Germination of Rumex crispus L. Seeds Induced by Temperature Shifts
High germination of curly dock (Rumex crispus L.) seeds is evident after suitable imbibition and temperature shift treatment, but germination at constant temperatures fails without an input of far red-absorbing form of phytochrome. Preliminary imbibitions at high temperatures (30 C) sharply reduce germination induced by temperature shifts. High germination may be restored by low energies of red radiation, or by brief far red adequate for the photosteady state. Prolonged far red during imbibition also nullifies temperature shift-induced germination. After prolonged far red, high germination may be restored by red radiation of an energy dependent upon the duration of the far red treatment. The evidence supports the conclusion that dark germination induced by temperature shifts arises from the interaction of pre-existent far red-absorbing form of phytochrome in the mature seeds with the temperature shift.
Taylorson, R. B.; Hendricks, S. B.
Seed flotation and germination of salt marsh plants: The effects of stratification, salinity, and/or inundation regime
We examined the effects of cold stratification and salinity on seed flotation of eight salt marsh species. Four of the eight species were tested for germination success under different stratification, salinity, and flooding conditions. Species were separated into two groups, four species received wet stratification and four dry stratification and fresh seeds of all species were tested for flotation and germination. Fresh seeds of seven out of eight species had flotation times independent of salinity, six of which had average flotation times of at least 50 d. Seeds of Spartina alterniflora and Spartina patens had the shortest flotation times, averaging 24 and 26 d, respectively. Following wet stratification, the flotation time of S. alterniflora seeds in higher salinity water (15 and 36 ppt) was reduced by over 75% and germination declined by more than 90%. Wet stratification reduced the flotation time of Distichlis spicata seeds in fresh water but increased seed germination from 2 to 16% in a fluctuating inundation regime. Fresh seeds of Iva frutescens and S. alternflora were capable of germination and therefore are non-dormant during dispersal. Fresh seeds of I. frutescens had similar germination to dry stratified seeds ranging 25-30%. Salinity reduced seed germination for all species except for S. alterniflora. A fluctuating inundation regime was important for seed germination of the low marsh species and for germination following cold stratification. The conditions that resulted in seeds sinking faster were similar to the conditions that resulted in higher germination for two of four species. ?? 2009 Elsevier B.V.
Elsey-Quirk, T.; Middleton, B. A.; Proffitt, C. E.
Nitric oxide implication in the control of seed dormancy and germination
Germination ability is regulated by a combination of environmental and endogenous signals with both synergistic and antagonistic effects. Nitric oxide (NO) is a potent dormancy-releasing agent in many species, including Arabidopsis, and has been suggested to behave as an endogenous regulator of this physiological blockage. Distinct reports have also highlighted a positive impact of NO on seed germination under sub-optimal conditions. However, its molecular mode of action in the context of seed biology remains poorly documented. This review aims to focus on the implications of this radical in the control of seed dormancy and germination. The consequences of NO chemistry on the investigations on both its signaling and its targets in seeds are discussed. NO-dependent protein post-translational modifications are proposed as a key mechanism underlying NO signaling during early seed germination.
Arc, Erwann; Galland, Marc; Godin, Beatrice; Cueff, Gwendal; Rajjou, Loic
A season- and gap-detection mechanism regulates seed germination of two temperate forest pioneers.
The survival of seedlings in temperate climate habitats depends on both temporal and spatial factors. The interaction between an internal seed dormancy mechanism and the ruling environmental conditions allows accurate cueing of germination. We analysed how environmental signals interact in seeds of temperate forest pioneer species, increasing the seed's chances of germinating in the right place at the right time. Digitalis purpurea and Scrophularia nodosa are two small-seeded herbaceous species that typically grow in vegetation gaps in European temperate forests. Seeds of both species are partially dormant at the time of dispersal in summer. This primary dormancy is released in autumn and early winter, resulting in a minimal level of physiological dormancy by late winter and early spring. We observed that physiological dormancy was induced again in seeds exhumed in late spring and in summer. Experiments in laboratory conditions revealed that primary dormancy in seeds of S nodosa was broken by cold stratification, whereas primary dormancy in D. purpurea seeds was broken by both a cold and a warm stratification. The two species differed in their response to the tested gap-detection signals, as light was the most important factor stimulating germination of D. purpurea, and seeds of S. nodosa germinated best when subjected to daily fluctuating temperatures. This study clearly indicates that the ability to germinate in response to gap-detection signals changes seasonally in temperate forest pioneers. Additionally, seeds of both species responded differently to these environmental signals, probably reflecting differences in the regeneration niche. PMID:22188020
Vranckx, G; Vandelook, F
Seed germination of a newly discovered hyperaccumulator Solanum nigrum L. affected by illumination and seed-soaking reagent
Solanum nigrum is a newly found Cd-hyperaccumulator which showed very high remediation efficiency in polluted soil. Seed germination experiments with different illumination and seed-soaking reagents were conducted in constant temperature box and greenhouse with soil as burgeon base. The results showed that the germination rate with alternating light\\/dark photoperiod was about twice of that without lighting (p<0.05), suggesting that illumination
Shuhe Wei; Yahu Hu; Mrittunjai Srivastava; Qixing Zhou; Rongcheng Niu; Yunmeng Li; Zhijie Wu; Tieheng Sun
Heat shock effects on seed germination of five Brazilian savanna species.
Fire is considered an important factor in influencing the physiognomy, dynamics and composition of Neotropical savannas. Species of diverse physiognomies exhibit different responses to fire, such as population persistence and seed mortality, according to the fire frequency to which they are submitted. The aim of this study is to investigate the effects of heat shocks on seed germination of Anadenanthera macrocarpa (Benth.) Brenan, Dalbergia miscolobium Benth., Aristolochia galeata Mart. & Zucc., Kielmeyera coriacea (Spreng.) Mart. and Guazuma ulmifolia Lam., which are native species of the Brazilian savanna. The temperatures and exposure times to which the seeds were submitted were established according to data obtained in the field during a prescribed fire: 60 °C (10, 20 and 40 min), 80 °C (5, 10 and 20 min) and 100 °C (2, 5 and 10 min). Untreated seeds were used as controls. Seeds of A. galeata and K. coriacea showed high tolerance to most heat treatments, and seeds of A. macrocarpa showed a significant reduction in germination percentage after treatments of 80 °C and 100 °C. Treatments of 100 °C for 10 min reduced germination percentage for all species except G. ulmifolia, which has dormant seeds. For this species, germination was accelerated by heat treatments. The high temperatures applied did not interfere with the time to 50% germination (T(50) ) of the tolerant seeds. Seeds of the savanna species K. coriacea and A. galeata were more tolerant to heat shocks than seeds of the forest species A. macrocarpa. Guazuma ulmifolia, the forest species with seeds that germinate after heat shock, also occurs in savanna physiognomies. Overall, the high temperatures applied did not affect the germination rate of the tolerant seeds. PMID:22672775
Ribeiro, L C; Pedrosa, M; Borghetti, F
Morphology, ecophysiology and germination of seeds of the neotropical tree Alibertia patinoi (Rubiaceae).
Alibertia patinoi (Rubiaceae) is of economic and cultural importance for communities in the Colombian Pacific and Amazon regions, where it is cultivated and mature fruits are highly appreciated and consumed. Since there is a lack of knowledge of the seed physiology of this species, we describe here the germination behavior and morphometry of seeds of Alibertia patinoi, and relate them to its habitat. Fruits were collected from a mixed food crop and a commercial plantation in Guaimía village, Buenaventura, Colombia, a tropical rain forest area. We measured length, width, thickness, mass (n = 1 400), and moisture content of seeds (n = 252). Primary dormancy tests were conducted (n = 200), followed by imbibition (n=252) and germination dynamics, under different conditions of light and temperature specific to understory and forest clearings (n = 300 seeds). Finally, seed storage behavior was established (n = 100 seeds). We observed that size and mass of seeds had a narrow range of values that did not differ within or among fruits and that the species did not exhibit primary dormancy. The seeds are recalcitrant, and recently harvested seeds exhibited higher seed moisture content (ca. 44%) and continuous metabolism. The seed germination percentage was observed to be higher under the specific dense canopy forest light and temperature conditions; furthermore, neither enriched far-red light nor darkness conditions inhibited germination. We concluded that rapid germination could be the establishment strategy of this species. Also, the physiological traits (i.e., rapid germination rate, low germination requirements, absence of primary dormancy, and recalcitrant behavior) and seed size and mass, suggest that A. patinoi is adapted to conditions of mature tropical rain forests. PMID:23885573
Escobar Escobar, Diego Fernando; Torres, Alba Marina
The Influence of Media on the Seed Germination of Depulped and Undepupled Fruits of Bush Mango Irvingia Wombolu)
Seed germination of depulped and undepulped fruits of bush mango, Irvingia wombolu (Vermeosen) were evaluated using six different media; Top forest soil (TS), sawdust (SD), Riversand (RS), 1:1 mixture of TS+SD,SD+RS and TS+RS, Undepuled fruits, despite slightly increased percentage germination in the mixed media, had very poor seed germination response in all the media. Seed germination of depulped fruits was
Dynamics and partitioning of the ionome in seeds and germinating seedlings of winter oilseed rape.
Germination and seedling establishment are among the most critical phases in the development of plants, and seed vigour has become an important trait for the selection of robust crop cultivars. Little is known about the potentially limiting role of mineral nutrients in early metabolic and developmental processes during germination. Therefore, we assessed the ionome and relative distribution of mineral elements in different seed and seedling tissues of oilseed rape (Brassica napus L.) and monitored the internal allocation of nutrients during germination. In seeds, cotyledons harboured the main pool of K, P, S, Mg, Fe, Mn and Zn, whereas the seed coat contained most of the Ca, Na, B, Cu and Mo. Although the early root and hypocotyl tissue expanded first, concentrations of most elements were initially low. Re-allocation of elements to the root/hypocotyl tissue from other pools set in two days after seed imbibition and was most rapid for K. Relative to the critical deficiency levels of vegetative tissues, seed tissues were particularly low in B, K and Fe. Further analyses of the ionome of seeds and seedlings, grouped according to their germination efficiency, indicated that in particular low S, Mg and Ca coincided with germination failure. This study documents highly dynamic changes in the ionome of seed and seedling tissues and provides evidence for potentially limiting elements during early germination and seedling establishment in rapeseed. PMID:23939714
Eggert, Kai; von Wirén, Nicolaus
The California chaparral community has a rich flora of species with different mechanisms for cuing germination to postfire conditions. Here we report further germination experiments that elucidate the response of several widespread shrub species whose germination response was not clear and include other species from the Sierra Nevada, which have not previously been included in germination studies. The shrubs Adenostoma
Jon E. Keeley; Thomas W. McGinnis; Kim A. Bollens
4. The role of plant growth regulators in the germination of forest tree seeds
To establish a role for PGRs in the germination of forest tree seeds, it must be demonstrated that PGRs are involved in the mechanisms that control the induction of and release from dormancy, and also that these mechanisms are operative in the seeds of woody plants. Four currently known concepts of seed dormancy are reviewed, citing the published evidence relating
C. L. Leadem
Seed Germination and Reproductive Features of Lysimachia minoricensis (Primulaceae), a Wild-extinct Plant
Lysimachia minoricensis is one of the few Mediterranean endemic plants (Minorca, Balearic islands) that has gone extinct in the wild but which persists as extant germplasm or cultivated plants in several botanical gardens. Reproductive features (seed set, number of seeds per capsule, seed weight) and germination responses to constant temperatures, sea water and dry-heat pre-treatments were investigated to determine the
Development of a threshold model to predict germination of Populus tomentosa seeds after harvest and storage under ambient condition.
Effects of temperature, storage time and their combination on germination of aspen (Populus tomentosa) seeds were investigated. Aspen seeds were germinated at 5 to 30°C at 5°C intervals after storage for a period of time under 28°C and 75% relative humidity. The effect of temperature on aspen seed germination could not be effectively described by the thermal time (TT) model, which underestimated the germination rate at 5°C and poorly predicted the time courses of germination at 10, 20, 25 and 30°C. A modified TT model (MTT) which assumed a two-phased linear relationship between germination rate and temperature was more accurate in predicting the germination rate and percentage and had a higher likelihood of being correct than the TT model. The maximum lifetime threshold (MLT) model accurately described the effect of storage time on seed germination across all the germination temperatures. An aging thermal time (ATT) model combining both the TT and MLT models was developed to describe the effect of both temperature and storage time on seed germination. When the ATT model was applied to germination data across all the temperatures and storage times, it produced a relatively poor fit. Adjusting the ATT model to separately fit germination data at low and high temperatures in the suboptimal range increased the models accuracy for predicting seed germination. Both the MLT and ATT models indicate that germination of aspen seeds have distinct physiological responses to temperature within a suboptimal range. PMID:23658654
Wang, Wei-Qing; Cheng, Hong-Yan; Song, Song-Quan
Seed storage conditions change the germination pattern of clonal growth plants in Mediterranean salt marshes
The effect of salinity level and extended exposure to different salinity and flooding conditions on germination patterns of three saltmarsh clonal growth plants (Juncus subulatus, Scirpus litoralis, and S. maritimus) was studied. Seed exposure to extended flooding and saline conditions significantly affected the outcome of the germination process in a different, though predictable, way for each species, after favorable conditions for germination were restored. Tolerance of the germination process was related to the average salinity level measured during the growth/germination season at sites where established individuals of each species dominated the species cover. No relationship was found between salinity tolerance of the germination process and seed response to extended exposure to flooding and salinity conditions. The salinity response was significantly related to the conditions prevailing in the habitats of the respective species during the unfavorable (nongrowth/nongermination) season. Our results indicate that changes in salinity and hydrology while seeds are dormant affect the outcome of the seed-bank response, even when conditions at germination are identical. Because these environmental-history-dependent responses differentially affect seed germination, seedling density, and probably sexual recruitment in the studied and related species, these influences should be considered for wetland restoration and management.
Espinar, J. L.; Garcia, L. V.; Clemente, L.
A Comparison Of Barley Malt Amylolytic Enzyme Thermostabilities As Indicators Of Malt Sugar Concentrations
This study was conducted to test the hypothesis that barley malt amylolytic enzyme thermostabilities would correlate negatively with malt sugar concentrations. Seeds of four two-row and four six-row North American elite barley cultivars were steeped and germinated in a micromalter for 6 days. At 2...
A Comparison of Barley Malt Amylolytic Enzyme Activities and Malt Sugar Concentrations
This study was conducted to test the hypothesis that barley malt alpha-amylase activity would correlate better with malt sugar concentrations than the activities of beta-amylase, or limit dextrinase. Seeds of four two-row and four six-row North American elite barley cultivars were steeped and germin...
Microflora of barley kernels.
Numbers and kinds of microflora were determined in 160 samples of barley grown in different regions of the United States; microflora were more abundant in the grains grown in the central states than in those grown in the western states. During steeping and germination in micromalting equipment, the number of colonies of filamentous fungi increased from two to five times, colonies of yeasts from five to ten times, and bacteria from 50 to more than 100 times the numbers present in the grain before malting. Kiln drying according to a commercial schedule reduced the number of all types of microflora below the number present before kilning, but all were present in larger numbers in the kilned malt than in the original grain. In barley stored at room temperature and at a moisture content of 15 to 18%, members of the Aspergillus glaucus group increased with increasing time and increasing moisture content, and germination percentage of the seeds decreased. Stored free of storage fungi at room temperature, barley with a moisture content just over 15% retained a high germination percentage for 5 months, but at a moisture content of 16% the germination decreased to zero. PMID:13893856
Isolation and characterization of inhibitors of animal cell-free protein synthesis from barley seeds
Three inhibitors of animal cell-free protein synthesis were isolated from barley seeds by ammonium sulfate fractionation,\\u000a CM-cellulose chromatography and gel filtration on Bio-Gel P-60. The three inhibitors were all single chain, basic proteins\\u000a with molecular weights about 31,000 and with very similar amino acid compositions. In the rabbit reticulocyte lysate system,\\u000a they inhibited in vitro translation to 50% at concentrations
Katsuhiko Asano; Birte Svensson; Flemming M. Poulsen
Hydrogen peroxide scavenging regulates germination ability during wheat (Triticum aestivum L.) seed maturation.
Hydrogen peroxide (H(2)O(2)) promotes seed germination of cereal plants and ascorbic acid which acts as antioxidant suppresses the germination of wheat seeds, but the role of H(2)O(2) scavenging on germination during seed maturation has not been demonstrated. We investigated relationship of germination, ascorbate, H(2)O(2) scavenging enzymes and sensitivity to ascorbic acid (AsA) maturing seeds of two typical wheat (Triticum aestivum L.) cultivars, cvs. Shirogane-Komugi and Norin61. Shirogane-Komugi had marked high germination ability than Norin61 during seed maturation. Although the H(2)O(2) content had no difference in the two culti-vars, sensitivity to AsA of Norin61 seeds was higher than that of Shirogane-Komugi seeds during seed maturation. The sensitivity to AsA closely correlated with germination characteristic in the two cultivars. Especially, at 28 days after pollination (DAP), sensitivity to AsA in Norin61 seeds was remarkably high. At that stage, no significant differences were observed in endogenous AsA level, ascorbate peroxidase (APX, EC 220.127.116.11) and dehydroascorbate reductase (DHAR, EC 126.96.36.199) activities in the two cultivars. However, catalase (CAT, EC 126.96.36.199) activity and CAT mRNA in Norin61 were remarkably higher than in Shirogane-Komugi. Sensitivity to AsA at 35 and 42 DAPs kept high levels in Norin61, and endogenous AsA and CAT activity in the seeds were significantly higher than in Shirogane-Komugi. These results revealed a direct correlation between germination and antioxidant sensitivity during the developmental stages of wheat seeds. PMID:19513213
Ishibashi, Yushi; Yamamoto, Kouhei; Tawaratsumida, Tomoya; Yuasa, Takashi; Iwaya-Inoue, Mari
The effect of fruit age on seed germinability of a heterocarpic species, Atriplex sagittata.
Atriplex sagittata is an annual heterocarpic plant that produces three different fruit types (termed A, B, and C). To examine the consequence of heterocarpy on germinability patterns over long time periods, we compared seed germinability of different fruit types that had been stored for up to 8 years. While germinability of non-dormant type C fruits in distilled water was high (up to 100 %) in the first 2 years, it rapidly decreased over time. Dormant fruit types A and B showed increased germinability up to 7 years, though loss of germinability was lower for type B than for type A fruits. Eight-year-old fruits of all types had significantly lower germinability than younger fruits, probably due to loss of viability. Heterocarpy, therefore, ensures that emergence rates for seedlings of A. sagittata will be maintained over relatively long periods, even in years of strong disturbance when all adult plants may be destroyed. The experiment further showed that germinability of all fruit types in high concentrations of salt, as compared with water treatment, changed over the course of 8 years. Whilst dormant types (A and B) of A. sagittata show increased germinability with age of the seed in water treatment, they significantly lose germinability over time with salinity treatment. Type C fruit was not influenced by salt in the first year, but germinability rapidly decreased with time. It follows that the species is able to germinate under high salt concentration in the first year, but this advantage gradually disappears. PMID:15570477
Mandák, B; Holmanová, S
Optimization of chitosan treatments for managing microflora in lettuce seeds without affecting germination.
Many studies have focused on seed decontamination but no one has been capable of eliminating all pathogenic bacteria. Two objectives were followed. First, to assess the in vitro antimicrobial activity of chitosan against: (a) Escherichia coli O157:H7, (b) native microflora of lettuce and (c) native microflora of lettuce seeds. Second, to evaluate the efficiency of chitosan on reducing microflora on lettuce seeds. The overall goal was to find a combination of contact time and chitosan concentration that reduces the microflora of lettuce seeds, without affecting germination. After treatment lettuce seeds presented no detectable microbial counts (<10(2)CFU/50 seeds) for all populations. Moreover, chitosan eliminated E. coli. Regardless of the reduction in the microbial load, a 90% reduction on germination makes imbibition with chitosan, uneconomical. Subsequent treatments identified the optimal treatment as 10 min contact with a 10 g/L chitosan solution, which maintained the highest germination percentage. PMID:23218371
Gońi, M G; Moreira, M R; Viacava, G E; Roura, S I
Effects of waterlogging on seed germination of three Mediterranean oak species: Ecological implications
Soil water saturation during prolonged periods of time generates a negative impact on nearly all terrestrial plants. In Mediterranean woodlands, precipitation can be very abundant during the wet season, inducing temporary soil waterlogging, coinciding with the seed dispersal and germination time of many species. We investigated the effects of waterlogging on seed germination and early root growth of three coexisting oak species ( Quercus canariensis, Q. suber and Q. pyrenaica), by completely flooding of seeds for various periods of time. The three oak species showed a certain level of tolerance to waterlogging, only being affected those seeds subjected for long periods of submersion (over 30 days). Waterlogging during prolonged periods of time decreased the probability of seed germination in the three oak species, lengthened the time to germination, and hampered root development in two of the studied species. The main differences between oak species occurred in terms of root growth ( Q. canariensis being the less affected, and Q. suber the most); these differential responses could be related to a species rank of waterlogging tolerance. Thus inter-specific differences in germination responses to waterlogging could contribute to explain, at least partially, species habitat and distribution patterns across landscapes. Seed mass also played an important role on different aspects of germination, though its relative importance varied as function of species and waterlogging treatment. The tolerance to stress induced by waterlogging increased with seed mass, but only in the case of Q. canariensis.
Pérez-Ramos, Ignacio M.; Marańón, Teodoro
Protein Mobilization in Germinating Mung Bean Seeds Involves Vacuolar Sorting Receptors and Multivesicular Bodies1[W][OA
Plants accumulate and store proteins in protein storage vacuoles (PSVs) during seed development and maturation. Upon seed germination, these storage proteins are mobilized to provide nutrients for seedling growth. However, little is known about the molecular mechanisms of protein degradation during seed germination. Here we test the hypothesis that vacuolar sorting receptor (VSR) proteins play a role in mediating protein degradation in germinating seeds. We demonstrate that both VSR proteins and hydrolytic enzymes are synthesized de novo during mung bean (Vigna radiata) seed germination. Immunogold electron microscopy with VSR antibodies demonstrate that VSRs mainly locate to the peripheral membrane of multivesicular bodies (MVBs), presumably as recycling receptors in day 1 germinating seeds, but become internalized to the MVB lumen, presumably for degradation at day 3 germination. Chemical cross-linking and immunoprecipitation with VSR antibodies have identified the cysteine protease aleurain as a specific VSR-interacting protein in germinating seeds. Further confocal immunofluorescence and immunogold electron microscopy studies demonstrate that VSR and aleurain colocalize to MVBs as well as PSVs in germinating seeds. Thus, MVBs in germinating seeds exercise dual functions: as a storage compartment for proteases that are physically separated from PSVs in the mature seed and as an intermediate compartment for VSR-mediated delivery of proteases from the Golgi apparatus to the PSV for protein degradation during seed germination.
Wang, Junqi; Li, Yubing; Lo, Sze Wan; Hillmer, Stefan; Sun, Samuel S.M.; Robinson, David G.; Jiang, Liwen
Seed germination during floatation and seedling growth of Carapa guianensis , a tree from flood-prone forests of the Amazon
Carapa guianensis Aubl. (Meliaceae), a hard wood tree from the Brazilian Amazon, has large recalcitrant seeds that can germinate and establish in both flood-free (terra-firme) and flood-prone (várzea) forests. These seeds, although large, can float. This study was designed to experimentally examine seed longevity under floating conditions ex-situ and its effects on subsequent germination and seedling growth. Many seeds germinated
Fábio R. Scarano; Tânia S. Pereira; Giselle Rôças
Temperature characteristics in seed germination and growth of Zostera japonica Ascherson & Graebner from Ago Bay, Mie Prefecture, central Japan
The optimal water temperature in seed germination and the upper critical water temperature in seedling growth were determined\\u000a for Zostera japonica collected from Ago Bay, Japan. The relationship between the seed germination rates and seed storage period (0, 30, and 60 days)\\u000a at 0°C was also examined. The optimal water temperature in seed germination was in the range 15–20°C regardless of
Mahiko Abe; Keigo Yokota; Akira Kurashima; Miyuki Maegawa
Comparison of the seed germination effects of synthetic analogs of strigol, gibberellic acid, cytokinins, and other plant growth regulators
Four synthetic multiring analogs of strigol, a naturally occurring sesquiterpene lactone that promotes germination of dormant seeds ofStriga (witchweed), were found to stimulate germination of dormantLactuca (lettuce) seeds. The effects on light-sensitive and light-insensitive lettuce seeds were concentration-dependent and exceeded those produced by equimolar (0.1 mM) solutions of gibberellic acid. Strigol and epistrigol promoted lettuce seed germination to a lesser
Judith M. Bradow; William J. Connick; Armand B. Pepperman
Copper Affects the Cotyledonary Carbohydrate Status During the Germination of Bean Seed
Seeds of bean (Phaseolus vulgaris L.) were germinated by soaking in distilled water or copper chloride solution. The relationships among copper excess treatment,\\u000a germination rate, dry weight, sugar contents, and carbohydrase activities in cotyledon were investigated. Heavy metal stress\\u000a provoked a diminution in germination rate and biomass mobilization, as compared with the control. A drastic disorder in soluble\\u000a sugars export,
Amira Sfaxi-Bousbih; Abdelilah Chaoui; Ezzedine El Ferjani
Histochemical studies on protease formation in the cotyledons of germinating bean seeds
Protease formation in Phaseolus vulgaris L. cotyledons during seed germination was studied histochemically using a gelatin-film-substrate method. Protease activity can be detected by this method on the 5th day of germination, at approximately the same time that a rapid increase of activity was observed by a test-tube assay with casein as a substrate. At the early stage of germination, protease
Harugoro Yomo; Margery Poole Taylor
Dynamics of indole-3-acetic acid during germination of Picea abies seeds.
High performance liquid chromatography and combined gas chromatography-mass spectrometry were used to identify indole-3-acetic acid (IAA) and indole-3-ethanol as endogenous constituents of germinating Norway spruce (Picea abies (L.) Karst.) seeds. Indole-3-methanol was tentatively identified by multiple ion monitoring. The free IAA content of the seeds rose from about 20 ng g(-1) to about 60 ng g(-1) (dry weight) during the first five days of germination and thereafter declined to around 20 ng g(-1). Indole-3-acetic acid released by alkaline hydrolysis, which was initially present at about 110 ng g(-1), decreased to 5-10 ng g(-1) during the first week of germination. The IAA content of seed lots differing in germination behavior was investigated. The findings are discussed in relation to the metabolism of IAA in conifer seeds. PMID:14975830
Sandberg, G; Ernstsen, A
Contribution of low molecular weight antioxidants to the antioxidant screen of germinated soybean seeds
Soybean seed of the Mazovia variety (Glycine max) were germinated in the dark at a constant temperature of 25°C up to 168 h (24 h × 7). Changes in content of low molecular weight antioxidants (LMWA) in the course of germination were studied. The analyzed compounds were: total phenolics, soluble proteins, tocopherols (a-T, ß-T, ? -T, d -T), reduced and
H. Zieli?ski
The effect of salinity level and extended exposure to different salinity and flooding conditions on germination patterns of three salt- marsh clonal growth plants (Juncus subulatus, Scirpus litoralis, and S. maritimus) was studied. Seed exposure to extended flooding and saline conditions significantly affected the outcome of the germination process in a different, though predictable, way for each species, after favorable
J. L. Espinar; L. V. Garcia; L. Clemente
Stimulation and Promotion of Germination in Opuntia ficus-indica Seeds
Opuntia ficus-indica seeds, as many other Opuntia species, show low germination capacity due mainly to their hard lignified integuments, the most inward of these is the funiculus that envelops the embryo, obstructing radicle protrusion. The purpose of this study was to accelerate the initiation of the germination process and to shorten their completion time by the action of physical and
Mariela Altare; Sinibaldo Trione; Juan C. Guevara; Mariano Cony
Environmental signals for seed germination reflect habitat adaptations in four temperate Caryophyllaceae
Summary 1. Requirements for dormancy break and seed germination are specific for all species and depend chiefly on phylogeny, geographical distribution, habitat preference and life cycle. Studying germina- tion requirements of closely related species with a similar geographic distribution allows one to attribute variation in germination requirements to differences in habitat preference between the species. 2. We investigated requirements for
F. Vandelook; D. Van de Moer; J. A. Van Assche
Germination, Respiration, and Adenylate Energy Charge of Seeds at Various Oxygen Partial Pressures
The effect of O2 partial pressure on the germination and the respiration of 12 cultivated species was studied. The reciprocal of the time necessary to observe rootlet emergence in 50% of the seeds was used to approach the germination rate. The maximum germination and respiration rates were reached in most seeds at O2 pressures close to that of air. Decreasing the O2 pressure produced a gradual decrease of the germination rate. The seeds could be classed in two groups according to their response to low O2 pressures. Group I includes lettuce, sunflower, radish, turnip, cabbage, flax, and soybean: at O2 pressures close to 2 kilopascals, the germination in this group was stopped and the adenylate energy charge was lower than 0.6. Group II includes rice, wheat, maize, sorghum, and pea. The germination rate of these seeds was also gradually decreased by lowering the O2 partial pressure but germination still occured, very slowly, at 0.1 kilopascal; the adenylate energy charge remained higher than 0.6. These differences in the germination rates and adenylate energy charge values could not be explained by differences in the sensitivity of respiration to O2.
Al-Ani, Ali; Bruzau, Francoise; Raymond, Philippe; Saint-Ges, Veronique; Leblanc, Jean Marc; Pradet, Alain
Light activates the degradation of PIL5 protein to promote seed germination through gibberellin in Arabidopsis
Summary Angiosperm seeds integrate various environmental signals, such as water availability and light conditions, to make a proper decision to germinate. Once the optimal conditions are sensed, gibberellin (GA) is synthesized, triggering germination. Among environmental signals, light conditions are perceived by phytochromes. However, it is not well understood how phytochromes regulate GA biosynthesis. Here we investigated whether phytochromes regulate GA
Eunkyoo Oh; Shinjiro Yamaguchi; Yuji Kamiya; Gabyong Bae; Won-Il Chung; Giltsu Choi
D-type cyclins activate division in the root apex to promote seed germination in Arabidopsis
Seeds provide survival and dispersal capabilities by protecting the dormant mature plant embryo. Germination and resumption of development under favourable conditions requires the reinitiation of cell growth and division through poorly understood processes. Here we show that four phases of cell division activation during germination in Arabidopsis are related to external morphological changes. Cell division initiates in the root apical
Nompumelelo H. Masubelele; Walter Dewitte; Margit Menges; Spencer Maughan; Carl Collins; Rachael Huntley; Jeroen Nieuwland; Simon Scofield; James A. H. Murray
Seed dormancy and germination of Ficus lundellii and tropical forest restoration.
We investigated seed dormancy and germination in Ficus lundellii Standl. (Moraceae), a native species of Mexico's Los Tuxtlas tropical rain forest. In an 8-h photoperiod at an alternating diurnal (16/8 h) temperature of 20/30 degrees C, germination was essentially complete (96%) within 28 days, whereas in darkness, all seeds remained dormant. Neither potassium nitrate (0.05-0.2%) applied continuously nor gibberellic acid applied either continuously (10-200 ppm) or as a 24 hour pretreatment (2000 ppm) induced germination in the dark. Germination in the light was not reduced by a 24-h hydrochloric acid (0.1-1%) pretreatment, but it was reduced both by a 24-h pretreatment with either H(2)O(2) (0.1-5 M) or 5% HCl, or by more than 5 days of storage at 40 degrees C (4.5% seed water content). In a study with a 2-dimensional temperature gradient plate, seeds germinated fully and rapidly in the light at a constant temperature of 30 degrees C, and fully but less rapidly in the light at alternating temperatures with low amplitudes (< 12 degrees C) about the optimal constant temperature. The base, optimal and ceiling temperatures for rate of germination were estimated as 13.8, 30.1 and 41.1 degrees C, respectively. In all temperature regimes, light was essential for the germination of F. lundellii seeds. PMID:16203717
Garcia, Ximena; Hong, Tran D; Ellis, Richard H
Effects of arsenic on seed germination and physiological activities of wheat seedlings
The effects of arsenic (As) were investigated on seed germination, root and shoot length and their biomass and some other factors to elucidate the toxicity of As. The results showed low concentrations of As (0–1 mg\\/kg) stimulated seed germination and the growth of root and shoot, however, these factors all decreased gradually at high concentrations of As (5–20 mg\\/kg). The
Chun-xi LI; Shu-li FENG; Yun SHAO; Li-na JIANG; Xu-yang LU; Xiao-li HOU
Germinated Cajanus cajan seeds as ingredients in pasta products: Chemical, biological and sensory evaluation
Pigeon peas (Cajanus cajan) seeds were germinated for 4 days at 20°C in darkness in order to improve the nutritional quality of seeds. Germination brought about a sharp reduction of ?-galactosides, phytic acid and trypsin inhibitor activity (83%, 61% and 36%, respectively) and an increment of vitamin B2 (145%), vitamin C (from negligible amounts to 14mg\\/100g d.m.), vitamin E (108%)
Alexia Torres; Juana Frias; Marisela Granito; Concepción Vidal-Valverde
Exogenous nitric oxide improves seed germination in wheat against mitochondrial oxidative damage induced by high salinity
Effects of exogenous nitric oxide (NO) on starch degradation, oxidation in mitochondria and K+\\/Na+ accumulation during seed germination of wheat were investigated under a high salinity level. Seeds of winter wheat (Triticum aestivum L., cv. Huaimai 17) were pre-soaked with 0mM or 0.1mM of sodium nitroprusside (SNP, as nitric oxide donor) for 20h just before germination under 300mM NaCl. At
Chunfang Zheng; Dong Jiang; Fulai Liu; Tingbo Dai; Weicheng Liu; Qi Jing; Weixing Cao
Effects of Seed-borne Fungi on Germination and Seedling Growth of Watermelon (Citrullus lanatus)
The effect of Mucor racemosus and Rhizopus nigricans inocula (1 & 0.1 g L -1 distilled water) and a seed dressing fungicide Seedplus® (1.25 g 500 g-1 seeds) on germination and seedling growth of watermelon (cv. Chaliston gray) was investigated. It was confirmed that the combined inocula with higher density caused significantly poor germination and seedling growth (P ? 0.05)
Lipid components of borage ( Borago officinalis L.) seeds and their changes during germination
The changes in composition of total and neutral lipids (NL) as well as glycolipids (GL) and phospholipids (PL) of borage (Borago officinalis L.) seeds, germinated in the dark at 25°C for 10 d, were studied. Total lipids constituted 34.0% of the dry matter of borage seeds. During germination, the content\\u000a of total lipids was decreased by 95%. NL accounted for
S. P. J. Namal Senanayake; Fereidoon Shahidi
Effect of the embryo axis on catalase in the endosperm of germinating castor bean seeds
The effect of the embryo axis on the activity of the glyoxysomal enzyme catalase (EC 220.127.116.11) in the endosperm of germinating castor bean (Ricinus communis L. cv. Hale) seeds was examined. The presence of the embryo axis was required for maximum levels of catalase enzyme activity and protein levels in cell-free extracts of endosperms from germinated seeds. In contrast, RNA
Robert T Mullen; David J Gifford
Action Spectra for Phytochrome A- and B-Specific Photoinduction of Seed Germination in Arabidopsis thaliana
We have examined the seed germination in Arabidopsis thaliana of wild type (wt), and phytochrome A (PhyA)- and B (PhyB)-mutants in terms of incubation time and environmental light effects. Seed germination of the wt and PhyA-null mutant (phyA) was photoreversibly regulated by red and far-red lights of 10-1,000 mu mol m-2 when incubated in darkness for 1-14 hr, but no
Tomoko Shinomura; Akira Nagatani; Hiroko Hanzawa; Mamoru Kubota; Masakatsu Watanabe; Masaki Furuya
Analysis of the dual role of phytochrome in the photoinhibition of seed germination
Light can both promote and inhibit germination, even of seeds of the same species1-3. Many seeds considered to be positively photoblastic are inhibited by prolonged irradiation with light of a wide variety of spectral qualities, including those, such as sunlight, that promote germination when given as a short exposure4. The promoting effect of light is mediated by the red\\/far-red reversible
Michael R. Bartley; Barry Frankland
Effects of waterlogging on seed germination, electric conductivity of seed leakage and developments of hypocotyl and radicle in sudangrass
Sudangrass (Sorghum sudanense Stapf) is a short-period forage species adapted to growth in Taiwan. The objectives of the experiment were to determine the effects of waterlogging on seed germination, electric con- ductivity of seed leakage and developments of hypocotyl and radicle in sudangrass and provide information for selecting the lines with tolerance to waterlogging stress. Sudangrass, CV. Taishi No. 1,
Fu-Hsing Hsu; Jeng-Bin Lin; Shyh-Rong Chang
Biochemical and biophysical changes associated with magnetopriming in germinating cucumber seeds.
Seeds of cucumber were exposed to static magnetic field strength from 100 to 250 mT for 1, 2 or 3 h. Germination-percentage, rate of germination, length of seedling and dry weight increased by 18.5, 49, 34 and 33% respectively in magnetoprimed seeds compared to unexposed seeds. Among different magnetic field doses, 200 mT for 1 h showed significant effect on germination parameters and hence selected for studying changes in water uptake, (1)H transverse relaxation time (T(2)), hydrolytic enzymes, reactive oxygen species and antioxidant enzyme system in germinating seeds. Water uptake and T(2) values were significantly higher in treated seeds during imbibition. The activities of hydrolytic enzymes, amylase and protease were greater than the untreated controls by 51% and 13% respectively. Superoxide radicals also enhanced by 40% and hydrogen peroxide by 8% in magnetically exposed seeds. In magetoprimed seeds, increased activities of antioxidant enzymes, superoxide dismutase (8%), catalase (83%) and glutathione reductase (77%) over control was recorded. We report that magnetopriming of dry seeds can be effectively used as a pre-sowing treatment for seed invigoration in cucumber. Unlike other priming treatments seed is not required to be dehydrated after priming, allowing easy storage. PMID:22683465
Bhardwaj, Jyotsna; Anand, Anjali; Nagarajan, Shantha
Changes in germination and potential longevity of watermelon (Citrullus lanatus) seeds during development
Changes in germination and potential seed longevity (Ki of the viability equation) were monitored during the development of watermelon (Citrullus lanatus) seeds grown in warm (minimum and maximum temperatures were 16.8 and 40.1°C) and cool (9.8 and 35.1°C) sites in 2002. Maximum seed weight (mass maturity, end of seed filling phase) was attained 25 days after anthesis (DAA) under both
Ibrahim Demir; Kazim Mavi; Canan Oztokat
Ecology of seed dormancy and germination in sedges ( Carex)
The genus Carex, with its wide distribution and large number of species yet with a rather uniform life history, is a very convenient group for comparative studies of germination ecology at the generic level. The combination of a strict or conditional primary dormancy, a light requirement for germination, low germination at constant temperatures, a positive response to diurnal temperature fluctuations
Wolfgang Schütz
Polyamine Anabolism in Germinating Glycine max (L.) Seeds 1
Active polyamine biosynthesis occurs in the embryonic axis, but not in the cotyledons, during germination of Glycine max (L.) cv Williams seeds and subsequent growth of the young seedlings. The hypocotyl and radicle synthesize and accumulate considerable amounts of cadaverine (Cad) and putrescine (Put) during the early stages of growth. Most of the amino acid precursors for the diamines are supplied from breakdown of the cotyledonary protein. In the axis, Cad synthesis which is catalyzed by l-lysine decarboxylase precedes the onset of growth (dry weight accumulation) of the axis and its accumulation continues as the growth progresses. After 2 days of imbibition, Cad is synthesized and accumulated at 37.4 nanomoles per axis per hour for at least 6 days. The rate then gradually decreases as the supply of free l-lysine from the cotyledons diminishes. Approximately 40 to 50% of the lysine resulting from breakdown of the cotyledonary protein ends up in Cad in the hypocotyl and radicle. Cad represents about 3.5% of the axis nitrogen derived from the cotyledons, which is equivalent to about 50% of the lysine content (?7%) of the seed protein. The synthesis and accumulation of Put in the axis also precedes the onset of growth of the axis. Both l-arginine decarboxylase and l-ornithine decarboxylase are involved in catalyzing the Put formation. The increased content of spermidine (Spd), but not spermine (Spm), parallels growth of the axis. Spm is maintained at a nearly undetectable level. After 2-day imbibition, Put and Spd are synthesized and accumulated at 0.94 and 0.17 nanomoles per axis per hour, respectively. The rate of Put accumulation, like that of Cad, decreases about 8 days after imbibition. The hypocotyl and radicle contain millimolar concentrations of Cad and Put which are primarily associated with the elongated zones. In contrast, Spd level or the molar ratio of Spd:Put appears to decrease as cell differentiation or elongation progresses.
Lin, Paul P. C.
Influence of Oxygen at High Pressure on the Induction of Damage in Barley Seeds by gamma Radiation.
The influence of oxygen pressure prior to, during, and after irradiation on the induction of radiation damage was investigated using Himalaya (C.I. 620) barley seeds. Seeds were adjusted to water contents of 2 to 14% and then irradiated with exp 60 Co gam...
E. Donaldson R. A. Nilan C. F. Konzak
Cytochrome C oxidase activity in germinating Phaseolus vulgaris l. seeds: Effects of carbon monoxide
Cytochrome c oxidase is a key bioenergetic enzyme required for seed germination. The enzyme was isolated from 2-day germinating beans and biochemically compared to its bovine heart counterpart. Carbon monoxide, which binds to the heme a{sub 3} site of cytochrome c oxidase, we used to probe O{sub 2} utilization activity in isolated enzyme, mitochondrial particles, and whole seeds. Bean seeds under 80% CO/20% O{sub 2} exhibited 46% growth inhibition as determined by root length. Reversible, dose-dependent partial inhibition of bean seed mitochondrial respiration was observed in the presence of CO; heart mitochondria had a more sensitive, less reversible response. Effects of CO on bean and bovine heart enzyme were similar. The close correlation of CO effects observed on seedling growth, mitochondrial respiration and cytochrome oxidase activity indicate an important role for this enzyme during the early stages of seed germination.
Caughey, W.S. (Colorado State Univ., Fort Collins (USA)); Sowa, S.; Roos, E.E.
Proteomics of Arabidopsis Seed Germination : a Comparative Study of Wild-Type and Gibberellin-Deficient Seeds
We examined the role of gibberellins (GAs) in germination of Arabidopsis seeds by a proteomic approach. For that purpose, we used two systems. The first system consisted of seeds of the GA-deficient ga1 mutant, and the second corresponded to wild-type seeds incubated in paclobutrazol, a specific GA biosynthesis inhibitor. With both systems, radicle protrusion was strictly dependent on exogenous GAs.
Karine Gallardo; Claudette Job; Steven P. C. Groot; Magda Puype; J. Vandekerckhove; D. Job
Effect of Water Stress on the Carbohydrate Metabolism of Citrullus lanatus Seeds during Germination.
Gluconeogenesis in Citrullus lanatus seeds is a post germinative event. Increases in isocitrate lyase activity and incorporation of radioactivity from [2-(14)C]acetate into sugars occur only after radicle emergence. During germination, the seeds appear to rely on carbohydrate as the respiratory substrate. At this time, glycolysis, the pentose phosphate pathway, and the tricarbocyclic acid cycle seem to be functional. Utilization of raffinose during germination appears to be important.Water stress, which completely inhibits germination, has a marked effect on carbohydrate metabolism. The rate of (14)CO(2) release from [2-(14)C]acetate, [1-(14)C]glucose, and [6-(14)C]glucose is lower in the stressed seeds than the control seeds during the respiratory lag phase. However, in the stressed seeds neither glycolysis, the pentose phosphate pathway, nor the tricarboxylic acid cycle is completely inhibited. In contrast to the control seeds in which raffinose content sharply declines after 12 h of incubation, raffinose content in the stressed seeds remains fairly constant.The respiratory lag phase of the control seeds coincides with a lower reducing substance content, glucose content, and fructose content than in the stressed seeds during the corresponding incubation period. PMID:16664032
Botha, F C; Small, J G
Transcriptional Dynamics of Two Seed Compartments with Opposing Roles in Arabidopsis Seed Germination1[W][OPEN
Seed germination is a critical stage in the plant life cycle and the first step toward successful plant establishment. Therefore, understanding germination is of important ecological and agronomical relevance. Previous research revealed that different seed compartments (testa, endosperm, and embryo) control germination, but little is known about the underlying spatial and temporal transcriptome changes that lead to seed germination. We analyzed genome-wide expression in germinating Arabidopsis (Arabidopsis thaliana) seeds with both temporal and spatial detail and provide Web-accessible visualizations of the data reported (vseed.nottingham.ac.uk). We show the potential of this high-resolution data set for the construction of meaningful coexpression networks, which provide insight into the genetic control of germination. The data set reveals two transcriptional phases during germination that are separated by testa rupture. The first phase is marked by large transcriptome changes as the seed switches from a dry, quiescent state to a hydrated and active state. At the end of this first transcriptional phase, the number of differentially expressed genes between consecutive time points drops. This increases again at testa rupture, the start of the second transcriptional phase. Transcriptome data indicate a role for mechano-induced signaling at this stage and subsequently highlight the fates of the endosperm and radicle: senescence and growth, respectively. Finally, using a phylotranscriptomic approach, we show that expression levels of evolutionarily young genes drop during the first transcriptional phase and increase during the second phase. Evolutionarily old genes show an opposite pattern, suggesting a more conserved transcriptome prior to the completion of germination.
Dekkers, Bas J.W.; Pearce, Simon; van Bolderen-Veldkamp, R.P.; Marshall, Alex; Widera, Pawel; Gilbert, James; Drost, Hajk-Georg; Bassel, George W.; Muller, Kerstin; King, John R.; Wood, Andrew T.A.; Grosse, Ivo; Quint, Marcel; Krasnogor, Natalio; Leubner-Metzger, Gerhard; Holdsworth, Michael J.; Bentsink, Leonie
Effects of Exogenous Silicon on Germination Characteristics of Cucumber Seeds under NaHCO3 Stress
The germination characteristics of cucumber seeds were determined after treatments of as follows: (1) the control (CK): distilled water; (2) Na: 70 mmol•L-1 NaHCO3; (3) S1 + Na: 0.01 mmol•L-1 silicon + 70 mmol•L-1 NaHCO3; (4) S2 + Na: 0.1 mmol•L-1 silicon + 70 mmol•L-1 NaHCO3. The results showed that the germination rate, germination potential, germination index, growing vigor index,
Yongdong Sun; Weirong Luo; Wenjie Zhang; Xiumei Zhou
A rapid response of beta-amylase to nitric oxide but not gibberellin in wheat seeds during the early stage of germination.
The effects of nitric oxide (NO) and gibberellic acid (GA(3)) on the responses of amylases in wheat (Triticum aestivum L.) seeds (caryopses) were investigated during the first 12 h of germination. GA(3) had no effects on the activities of alpha-amylase (EC 18.104.22.168) or beta-amylase (EC 184.108.40.206), either in intact seeds or embryoless halves within 12 h. In contrast, addition of sodium nitroprusside (SNP), an NO donor, was able to induce a rapid increase in beta-amylase activity without affecting alpha-amylase. Furthermore, the rapid response of beta-amylase to SNP in wheat seeds could be attributed to NO and was approximately dose-dependent. Some other aspects of SNP induction of amylase isozymes were also characterized. Further investigations showed that SNP might play an interesting role in the dissociation of free beta-amylase from small homopolymers or heteropolymers. Furthermore, SNP also directly induced the release of bound beta-amylase from glutenin and its crude enzyme preparation. However, the slight increase in protease also induced by SNP might not be responsible for this action. Interestingly, based on the fact that the rapid response of beta-amylase to NO also existed in seeds of other species, such as barley, soybean, rice and watermelon, it might be a universal event in early seed germination. PMID:15517355
Zhang, Hua; Shen, Wen-Biao; Zhang, Wei; Xu, Lang-Lai
Molecular and physiological dissection of enhanced seed germination using short-term low-concentration salt seed priming in tomato.
Seed germination is the initial step of plant development. Seed priming with salt promotes seed germination in tomato (Solanum lycopersicum L.); however, the molecular and physiological mechanisms underlying the enhancement of seed germination by priming remain to be elucidated. In this study, we examined the following in seeds both during and after priming treatment: the endogenous abscisic acid (ABA) and gibberellin (GA) concentrations; the expression of genes encoding ABA catabolic and GA biosynthesis enzymes, including 8'-hydroxylase (CYP707A), copalyl diphosphate synthase (CPS), GA 20-oxidase (GA20ox) and GA 3-oxidase (GA3ox); and endosperm cap weakening enzymes, including expansin (EXP), class I ?-1,3-glucanase (GulB), endo-?-mannanase (MAN) and xyloglucan endotransglucosylase (XTH). Tomato seeds were soaked for 24 h at 25 °C in the dark in 300 mM NaCl (NaCl-priming) or distilled water (hydro-priming). For both priming treatments, the ABA content in the seeds increased during treatment but rapidly decreased after sowing. Both during and after the priming treatments, the ABA levels in the hydro-primed seeds and NaCl-primed seeds were not significantly different. The expression levels of SlGA20ox1, SlGA3ox1 and SlGA3ox2 were significantly enhanced in the NaCl-primed seeds compared to the hydro-primed seeds. The GA(4) content was quantifiable after both types of priming, indicating that GA(4) is the major bioactive GA molecule involved in tomato seed germination. The GA(4) content was significantly higher in the NaCl-primed seeds than in the hydro-primed seeds 12 h after sowing and thereafter. Additionally, the peak expression levels of SlEXP4, SlGulB, SlMAN2 and SlXTH4 occurred earlier and were significantly higher in the NaCl-primed seeds than in the hydro-primed seeds. These results suggest that the observed effect of NaCl-priming on tomato seed germination is caused by an increase of the GA(4) content via GA biosynthetic gene activation and a subsequent increase in the expression of genes related to endosperm cap weakening. PMID:22305065
Nakaune, Makoto; Hanada, Atsushi; Yin, Yong-Gen; Matsukura, Chiaki; Yamaguchi, Shinjiro; Ezura, Hiroshi
Influence of temperature and salinity on germination of eelgrass ( Zostera marina L.) seeds
Seagrass restoration as part of ocean ecosystem protection has been launched for many years all over the world, but intensive research on this subject in China has just begun in recent years. Seed broadcasting has been widely accepted as the most potentially useful method for seagrass restoration over large areas. We examined the influence of key environmental factors on seed germination to help promote eelgrass bed restoration. Under anoxic conditions, the influence of temperature and salinity on the germination rate of eelgrass ( Zostera marina L.) seeds was examined at different combinations of four temperatures (4, 9, 14, and 24°C) and nine salinities (5 to 45, increment of 5). The effect of significant interaction of temperature and salinity on germination rate was observed (ANOVA) ( P<0.001). The highest germination rate (83.3 ± 3.5)% was reached in 8 weeks at 14°C and salinity 5. Higher temperature significantly increased the germination rate at salinity 5 ( P<0.001) during the whole observation period except for 24°C, while lower salinity significantly increased the germination rate at 14°C ( P<0.001). Although significant interaction was found between temperature and salinity ( P<0.001), the influence of salinity was stronger than that of temperature for the germination of eelgrass seeds. These results provide useful information for the propagation of artificial seedlings for seagrass restoration in China.
Pan, Jinhua; Jiang, Xin; Li, Xiaojie; Cong, Yizhou; Zhang, Zhuangzhi; Li, Zhiling; Zhou, Weili; Han, Houwei; Luo, Shiju; Yang, Guanpin
Induction of seed germination in Orobanche spp. by extracts of traditional Chinese medicinal herbs.
The co-evolution of Orobanche spp. and their hosts within the same environment has resulted in a high degree of adaptation and effective parasitism whereby the host releases parasite germination stimulants, which are likely to be unstable in the soil. Our objective was to investigate whether extracts from non-host plants, specifically, Chinese medicinal plants, could stimulate germination of Orobanche spp. Samples of 606 Chinese medicinal herb species were extracted with deionized water and methanol. The extracts were used to induce germination of three Orobanche species; Orobanche minor, Orobanche cumana, and Orobanche aegyptiaca. O. minor exhibited a wide range of germination responses to the various herbal extracts. O. cumana and O. aegyptiaca exhibited an intermediate germination response to the herbal extracts. O. minor, which has a narrow host spectrum, showed higher germination rates in response to different herbal extracts compared with those of O. cumana and O. aegyptiaca, which have a broader host spectrum. Methanolic extracts of many Chinese herbal species effectively stimulated seed germination among the Orobanche spp., even though they were not the typical hosts. The effective herbs represent interesting examples of potential trap crops. Different countries can also screen extracts from indigenous herbaceous plants for their ability to induce germination of Orobanche spp. seeds. The use of such species as trap plants could diminish the global soil seed bank of Orobanche. PMID:22527522
Ma, YongQing; Zhang, Wei; Dong, ShuQi; Ren, XiangXiang; An, Yu; Lang, Ming
The transcriptomes of dormant leafy spurge seeds under alternating temperature are differentially affected by a germination-enhancing pretreatment
Seed dormancy is an important stage in the life cycle of many non-domesticated plants, often characterized by the temporary failure to germinate under conditions that normally favor the process. Pre-treating dormant imbibed seeds at a constant temperate accelerated germination of leafy spurge seeds ...
Effects of light, hydropriming and abiotic stress on seed germination, and shoot and root growth of pyrethrum ( Tanacetum cinerariifolium)
Poor germination and seedling establishment are major problems in arid and semi-arid environments, and these characteristics are considered to be important factors in later plant growth and yield. Laboratory experiments were conducted on freshly harvested pyrethrum (Tanacetum cinerariifolium) seeds to investigate the effects of light (influenced by the seeding method) and seed hydropriming on germination, and shoot and root growth
J. Li; L. Y. Yin; M. A. Jongsma; C. Y. Wang
Protein Mobilization in Germinating Mung Bean Seeds Involves Vacuolar Sorting Receptors and Multivesicular Bodies1(W)(OA)
Plants accumulate and store proteins in protein storage vacuoles (PSVs) during seed development and maturation. Upon seed germination, these storage proteins are mobilized to provide nutrients for seedling growth. However, little is known about the molecular mechanisms of protein degradation during seed germination. Here we test the hypothesis that vacuolar sorting receptor (VSR) proteins play a role in mediating protein
Junqi Wang; Yubing Li; Sze Wan Lo; Stefan Hillmer; Samuel S. M. Sun; David G. Robinson; Liwen Jiang
Genetic relationships among cold, salt and drought tolerance during seed germination in an interspecific cross of tomato
Seed of BC1 progeny of an interspecific cross between a slow germinating Lycopersicon esculentum breeding line(NC84173; maternal and recurrent parent) and a fast germinating L.pimpinellifolium accession (LA722) were evaluated for germination under cold stress, salt stress and drought stress, and in each treatment\\u000a the most rapidly germinating seeds (first 2%) were selected. Selected individuals were grown to maturity and self-pollinated
M. R. Foolad; P. Subbiah; C. Kramer; G. Hargrave; G. Y. Lin
Traditional seed management and genetic diversity in barley varieties in high-hill agro-ecosystems of Nepal
Chawali and Lekali are two common farmer's barley varieties or landraces in Jumla, Nepal (2,240–3,000 m) with small to bold\\u000a grains and wide adaptation from irrigated low lands to high hills. This study was undertaken to test whether features of the\\u000a traditional seed system can significantly influence the diversity of a crop and its conservation on-farm. In Jumla (high-hill),\\u000a the barley
Jwala Bajracharya; Anthony H. D. Brown; Bal K. Joshi; Dipak Panday; Bimal K. Baniya; Bhuwon R. Sthapit; Devra I. Jarvis
Germination behaviour of seeds from herbicide treated plants of Chenopodium album L.
The carry-over effect of sub-lethal herbicides was investigated on the germination of seeds collected from surviving Chenopodium album plants, which had received 1/8, 1/8 twice, 1/8 three times, 1/4, 1/2, 1/1 doses of either pre-emergence ioxynil or post-emergence bentazone in a previous onion (Allium cepa) crop. Seeds were also collected from surviving C. album plants, which had received 1/4, 1/2, 1/1 of either pre-emergence pendimethalin, propachlor and linuron, or 1/8, 1/8 twice, 1/8 three times, 1/4, 1/2, 1/1 of post-emergence ioxynil or linuron in a previous leek (Allium porrum) crop. Seeds of surviving plants were collected and tested for germination at temperature of 5, 10, 15, 20 and 25 degrees C. The effect of different temperatures on the total number of germinated seeds was significant. Germination was minimum at low temperatures (5 degrees C or 10 degrees C). Herbicides did not show any effect on germination of C. album and resulted in the same final germination percentage as seeds collected from the unsprayed control plots. PMID:19893909
Tanveer, Asif; Nadeem, Muhammad A; Ali, Asghar; Tahir, Muhammad; Zamir, Muhammad S I
Change in protein content during seed germination of a high altitude plant Podophyllum hexandrum Royle.
Podophyllum hexandrum Royle (=Sinopodophyllum hexandrum) is a high-altitude medicinal plant exploited for its etoposides which are potential anticancer compounds. An effective, conventional propagation method is by seed. However, seed germination is erratic, and seedling survival is low. A marginal increase in Podophyllum seed germination was attained with organic solvents. In the present study an attempt was made to decipher the physiological and biochemical barriers in terms of change in proteins during seed germination of Podophyllum. Comparative 2-DE analysis between un-germinated (dormant) and germinating seeds revealed nearly 113 differentially expressed proteins, whereas Peptide Mass Fingerprint (PMF) analysis of 97 protein spots revealed appearance of 27 proteins, up-accumulation of 11 proteins, down-accumulation of 19 proteins and disappearance of 40 proteins with germination. Identified 59 proteins in the homology search were involved in metabolism (carbohydrate and amino acid metabolism; 20 proteins), ABA/GA signaling (17 proteins) and stress (15 proteins) related proteins. Seven proteins were with unknown function. Two-DE, and MS/MS analysis in conjunction with semi-quantitative RT-PCR data of cell wall hydrolyzing genes, revealed that in Podophyllum the radicle protrusion occurs might be because of the up-accumulation of cell wall hydrolases i.e. ?-1, 3-glucanase and XET which weakens the thick walled micropylar endosperm. PMID:23153791
Dogra, Vivek; Ahuja, Paramvir Singh; Sreenivasulu, Yelam
Pyrimidine nucleoside phosphorylation in developing seeds and germinating seedlings of wheat
Uridine- and thymidine-phosphorylating enzymes were measured in developing and germinating seeds of Triticum aestivum v. Arthur and T. aestivum v. Lemhi. Because crude extracts were to be used in the developmental study, characteristics of unpurified nucleoside phosphotransferase (NPTase) were examined. In the developmental study with two varieties of wheat, NPTase activity was found to be very low in all of the true seed tissues during seed maturation. Uridine-phosphorylating activity was due to primarily to uridine kinase. Thymidine phosphorylation was very low in all tissues throughout seed maturation, with a brief appearance by thymidine kinase in the developing embryo. In germinating seeds, uridine-phosphorylating activity was present from earliest stages of germination but showed a decrease in activity followed by a recovery after 48 hours inbibition. Experiments using ({alpha}-{sup 32}P)ATP indicated that uridine kinase was present during early germination but had disappeared by 96 hours. Uridine phosphorylation at later stages of germination was accomplished by NTPase. Thymidine phosphorylation did not begin until after 36 hours of germination and was the result of NPTase activity.
Rowe, M.L.
Seed Germination and Seedling Emergence of Three Annuals Growing on Desert Sand Dunes in China
? Background and Aims Information on the initial growth characteristics of annuals found in Chinese deserts is very limited. The aim of this study was to investigate seed germination and interactive effects of irrigation and seed burial depth in sand on seedling emergence and seedling survival in three annuals (Agriophyllum squarrosum, Bassia dasyphylla and Aristida adscensionis) commonly growing on sand
Influence of the testa on seed dormancy, germination and longevity in Arabidopsis
The testa of higher plant seeds protects the embryo against adverse environmental conditions. Its role is assumed mainly by controlling germination through dormancy imposition and by limiting the detrimental activity of physical and biological agents during seed storage. To analyze the function of the testa in the model plant Arabidopsis, we compared mutants affected in testa pigmentation and\\/or structure for
I. Debeaujon; K. M. Léon-Kloosterziel; M. Koornneef
Several phenolic acids, including p-coumaric acid, have been described as allelochemicals that may inhibit seed germination or seedling growth. Whether, in forage species, these effects are exacerbated by environmental stressors is not known. Accelerated seed aging (high temperature (41 C) and high...
Effect of Water uptake on Germinability in Seeds of Some Medicinal Plants, Uttarakhand, India
Three important medicinal plants of Uttarakhand, India were used in the present study. The effect of different imbibitions time and percentage were first time reported on seed germination and early seedling growth in Withenia somnifera, Pyracantha crinulata and Andographis paniculata. The initial weight of 800 seeds from each species were taken and dipped in water for imbibition. In every 3rd
Anoop Badoni; Mayank Nautiyal; Kiran Gusain; Manpreet Kaur; Rakhi Dhiman; Chetna Bisht; J. S. Chauhan
Thioredoxin-Linked Proteins Are Reduced during Germination of Medicago truncatula Seeds
Germination of cereals is accompanied by extensive change in the redox state of seed proteins. Proteins present in oxidized form in dry seeds are converted to the reduced state following imbibition. Thioredoxin (Trx) appears to play a role in this tran- sition in cereals. It is not known, however, whether Trx-linked redox changes are restricted to cereals or whether they
Fatima Alkhalfioui; Michelle Renard; William H. Vensel; Joshua Wong; Charlene K. Tanaka; William J. Hurkman; Bob B. Buchanan; Françoise Montrichard
Effects of Light, Cold Storage, and Temperature on Seed Germination of Golden Thistle (Scolymus hispanicus L.)
Golden thistle (Scolymus hispanicus L., family Asteraceae), is used as both a medicinal plant and a vegetable in the Mediterranean region. Although the plant grows in the wild, information to promote seed germination is needed for the cultivation necessary to meet demand. In this study, seed from two wild-grown and one cultivated source were used to determine the effect of
Ali Osman Sari; Mehmet Tutar
Distinct expression patterns of ?-1,3-glucanases and chitinases during the germination of Solanaceous seeds
The expression patterns of ? -1,3-glucanases (? Glu) and chitinases (Chn) were investigated during the seed germination of members of the Cestroideae (three Nicotiana species, Petunia hybrida) and the Solanoideae (Capsicum annuum, Physalis peruviana) subgroups of Solanaceous species. Rupture of the micropylar testa (seed coat) and rupture of the micropylar endosperm, i.e. radicle emergence, were distinct and temporally separate events
Luciana Petruzzelli; Kerstin Müller; Katrin Hermann; Gerhard Leubner-Metzger
Effect of high temperatures on seed germination of two woody Leguminosae
Cytisus scoparius and Genista florida regenerate after fire by stump-sprouting but also by seed. Seeds of these species were heated to a range of temperatures similar to those registered on the surface soil during natural fires (from 50 to 150 °C) and a range of exposure times (from 1 to 15 min). No germination was observed at high temperatures, =130
R. Tarrega; L. Calvo; L. Trabaud
Influence of the Testa on Seed Dormancy, Germination, and Longevity in Arabidopsis1
The testa of higher plant seeds protects the embryo against adverse environmental conditions. Its role is assumed mainly by controlling germination through dormancy imposition and by lim- iting the detrimental activity of physical and biological agents dur- ing seed storage. To analyze the function of the testa in the model plant Arabidopsis, we compared mutants affected in testa pigmen- tation
Isabelle Debeaujon; Karen M. Leon-Kloosterziel; Maarten Koornneef
Influence of seed nitrogen content and biofertilizer priming on wheat germination in salinity stress conditions
In order to study the effects of seed nitrogen content and biofertilizer priming on germination indices of wheat seeds under salinity stress, a factorial experiment based on a completely randomized design with four replications was conducted in 2009. Experimental factors consisted of: (1) the application of different nitrogen fertilizer rates (0, 55, 110 and 165 kg ha N) on parent
Jabbar Fallahi; Parviz Rezvani Moghaddam; Mahdi Nassiri Mahallati; Mohammad Ali Behdani; Mahsa Aghhavani Shajari; Mohammad Behzad Amiri
A genetic locus and gene expression patterns associated with the priming effect on lettuce seed germination at elevated temperatures
Seeds of most cultivated varieties of lettuce (Lactuca sativa L.) fail to germinate at warm temperatures (i.e., above 25–30°C). Seed priming (controlled hydration followed by drying)\\u000a alleviates this thermoinhibition by increasing the maximum germination temperature. We conducted a quantitative trait locus\\u000a (QTL) analysis of seed germination responses to priming using a recombinant inbred line (RIL) population derived from a cross
Andrés R. Schwember; Kent J. Bradford
Effects of rootzone CO2 and O2 levels on seed germination and stolon growth of Cynodon dactylon
The role of rootzone CO2 and O2 levels on seed germination and plant growth is not fully defined. The aim of the present study was to investigate the effects of supraoptimal CO2 in combination with different O2 concentrations on seed germination and the growth of pre-rooted stolon segments of Cynodon dactylon. Seeds of "Princess 77" were germinated in specialized airtight
Aimilia-Eleni Nikolopoulou; Panayiotis A. Nektarios; Georgios Aivalakis; Marco Volterrani; Ioannis Chronopoulos
The effects of Fusilade (Fluazifop- p -butyl) on germination, mitotic frequency and ?-amylase activity of lentil ( Lens culinaris Medik.) seeds
In this study, seed germination percentages, effects on phases of mitosis and ?-amylase enzyme activity of lentil seeds treated\\u000a with four different concentrations (0.25, 0.5, 1 and 1.5%) of Fusilade (Fluazifop-p-butyl) were determined. Median EC (effective concentration) values were calculated according to seed germination percentages\\u000a after treatment for 72 h. Germination percentages of primary lentil roots decreased with increasing Fusilade concentrations.
Feruzan Dane; Filiz Ekinci Sanal; Tulin Aktac
Micropropagation of a Casuarina hybrid ( Casuarina equisetifolia L. × Casuarina glauca Sieber ex Spreng) following facilitated seed germination
A suitable protocol for micropropagation of Casuarina hybrid, Casuarina equisetifolia L. × Casuarina glauca Sieber ex Spreng (C. e. × C. g.), was developed. When seeds without seed coats were cultured on 4 germination media, the optimal seed germination percentage\\u000a (91%) was obtained on 0.8% agar solidified water medium. Shoot multiplication was achieved by culturing 2-cm long epicotyls,\\u000a excised from germinated seedlings, on MS
Xiuli Shen; William S. Castle; Frederick G. Gmitter
Seed dispersal and germination patternsin a rare Mediterranean island endemic ( Anchusa crispa Viv., Boraginaceae)
We analyse and discuss patterns of seed dispersal and germination of a rare endemic plant species, Anchusa crispa Viv. (Boraginaceae) from Corsica and Sardinia. This coastal plant inhabits dunes and back-dunes, and currently numbers only a few thousand individuals which generally occur in isolated populations. This study included experiments conducted in the field in Corsica and also under controlled conditions in the laboratory. Short-distance dispersal of A. crispa is performed by ants, both by myrmecochory and dyszoochory. The invasion of an exotic species of ant, Linepithema humile, could locally modify the dispersal system and possibly the population dynamics of A. crispa. Long-distance dispersal may occur by water transport since seeds can germinate after at least 1 week of immersion in seawater and readily float on the surface. Burial of seeds is favourable for germination, percentage germination being maximised at a depth of 1-2 cm below the soil surface. A. crispa has a seed bank of about ten viable seeds per m 2, which may contribute to the survival of this species which exists in small populations with a short life span. Due to its seed dispersal and germination patterns, the conservation of this species will necessitate that human disturbance, which can destabilise the surface of the sand is prevented and that new populations are introduced to favourable sites.
Quilichini, Angélique; Debussche, Max
Endogenous gibberellins and kauranoids identified from developing and germinating barley grain
Several gibberellins (GAs) and kauranoids were identified in extracts of barley (Hordeum vulgare) by combined capillary gas chromatography-mass spectrometry (GC-MS). A partially purified acidic ethyl acetate extract from\\u000a 21-day postanthesis developing barley grain (cv. Proctor) contained GA1 (trace), GA4 (trace), GA8 (trace), GA12, GA17, GA20 (tentative) (trace), GA25, GA34, GA48, 18-hydroxy-GA4, 12?-hydroxy-GA9, and 18-hydroxy-GA34 (tentative). A hydrolyzed butanol extract contained
Paul Gaskin; Sarah Jane Gilmour; John R. Lenton; Jake MacMillan; Valerie M. Sponsel
WRI1 Is Required for Seed Germination and Seedling Establishment1
Storage compound accumulation during seed development prepares the next generation of plants for survival. Therefore, processes involved in the regulation and synthesis of storage compound accumulation during seed development bear relevance to germination and seedling establishment. The wrinkled1 (wri1) mutant of Arabidopsis (Arabidopsis thaliana )i s impaired in seed oil accumulation. The WRI1 gene encodes an APETALA2\\/ethylene-responsive element-binding protein transcription
Alex Cernac; Carl Andre; Susanne Hoffmann-Benning; Christoph Benning
Effect of electrostatic field on seed germination and seedling growth of Sorbus pohuashanesis
A study was conducted to determine the effects of electrostatic field (ESF) treatment on seed germination and seedling growth\\u000a of Sorbus pohuashanesis. The experiments were arranged by uniform design computed by the Data Processing System (DPS), including three levels of\\u000a seeds soaking time, four levels of ESF intensity and four levels of ESF treatment time, with 12 treatments. Ten seeds
Ling Yang; Hai-long Shen
Gibberellin requirement for Arabidopsis seed germination is determined both by testa characteristics and embryonic abscisic acid
The mechanisms imposing a gibberellin (GA) requirement to promote the germination of dormant and non-dormant Arabidopsis seeds were analyzed using the GA-deficient mutant ga1, several seed coat pigmentation and structure mutants, and the abscisic acid (ABA)-deficient mutant aba1. Testa mutants, which exhibit reduced seed dormancy, were not resistant to GA biosynthesis inhibitors such as tetcyclacis and paclobutrazol, contrarily to what
I. Debeaujon; M. Koornneef
[Effects of Larix gmelini aqueous extracts on seed germination and seedling growth of Juglans mandshurica].
In this study, Juglans mandshurica seeds were drenched in different concentrations (12.5, 25, 50 and 100 g x kg(-1)) aqueous extracts from adult Larix gmelini root, bark, branch and leaf for one week, and cultured in greenhouse in mid-April, 2004. The germination rate and germination index were calculated 18 days later, and the seedling's height and collar diameter were measured on August 1st. The results suggested that 25 g x kg(-1) root and 12.5 g x kg(-1) bark and branch aqueous extracts of L. gmelini could significantly increase the seed germination rate and germination index of J. mandshurica (P < 0.05), and 12.5 g x kg(-1) root and bark aqueous extracts could significantly increase the seedling height and collar diameter (P < 0.05). High concentrations of L. gmelini leaf aqueous extract could significantly promote the seed germination and seedling growth of J. mandshurica, but the promotion effect decreased gradually with decreasing concentration of leaf aqueous extract. The promotion of L. gmelini aqueous extracts to J. mandshurica seed germination and seedling growth might be related to the allelopathy between these two tree species. PMID:16964959
Yang, Lixue
Effect of Salinity on Seed Germination of Wheat Cultivars
Wheat (Triticum aestivum L.) is rated as moderately salt tolerant . Nevertheless, salinity reduces germination and delays emergence in this species and stands tend to be irregular with depressed crop yield. Some varieties, however, are less affected by salinity than others. In this study, our objective was to determine the effects of salinity on germination of a range of commercially
Seyfollah Fallah
Gibberellin Signaling: a Wake-up Call for Seed Germination
Making an appropriate decision to germinate is essential for the survival of plant species and is important for proper stand establishment in crop plants. Germination is regulated by the antagonistic effects to two plant hormones in Arabidopsis thaliana: abscisic acid (ABA) induces dormancy and repr...
Stratification Period and Germination of Douglas-Fir Seed from Oregon Seed Orchards: Two Case Studies.
Effect of stratification period (S) and incubation temperature (T) on germination behavior were tested by using two groups of Douglas-fir orchard seedlots that had given low germination percentages in standard tests. Seedlots with poor or slow germination...
F. C. Sorensen
Fire cue effects on seed germination of six species of northwestern Patagonian grasslands
Postfire recruitment of seedlings has been attributed to a stimulation of germination by fire-related cues. The germination response to heat shock (80 °C - 5 min), smoke (60 min), the combination of both factors and no heat no smoke (control) was studied in six native species (two dominant grasses, two dominant shrubs and two annual fugitive herbs) of northwestern Patagonian grasslands. Seeds of the grasses Festuca pallescens and Stipa speciosa and the shrub Senecio bracteolatus (Asteraceae) germinated when they were exposed to heat shock, whereas seeds of the other shrub, Mulinum spinosum (Apiaceae), were killed by this fire cue. In grasses, probably the glume of caryopsis protected embryos from heat. Possibly, the seed size could explain the different responses of the two shrubs. Heat combined with smoke reduced seed germination for S. speciosa and S. bracteolatus. The heat could have scarified seeds and the longer exposure to smoke could have been toxic for embryos. The same treatment increased germination of the annual fugitive herb Boopis gracilis (Calyceraceae). We concluded that fire differentially affects the seedling recruitment of the studied species in the northwestern Patagonian grasslands.
Gonzalez, S. L.; Ghermandi, L.
Overexpression of Nelumbo nucifera metallothioneins 2a and 3 enhances seed germination vigor in Arabidopsis.
Metallothioneins (MTs) are small, cysteine-rich and metal-binding proteins which are involved in metal homeostasis and scavenging of reactive oxygen species. Although plant MTs have been intensively studied, their roles in seeds remain to be clearly established. Here, we report the isolation and characterization of NnMT2a, NnMT2b and NnMT3 from sacred lotus (Nelumbo nucifera Gaertn.) and their roles in seed germination vigor. The transcripts of NnMT2a, NnMT2b and NnMT3 were highly expressed in developing and germinating sacred lotus seeds, and were dramatically up-regulated in response to high salinity, oxidative stresses and heavy metals. Analysis of transformed Arabidopsis protoplasts showed that NnMT2a-YFP and NnMT3-YFP were localized in cytoplasm and nucleoplasm. Transgenic Arabidopsis seeds overexpressing NnMT2a and NnMT3 displayed improved resistance to accelerated aging (AA) treatment, indicating their significant roles in seed germination vigor. These transgenic seeds also exhibited higher superoxide dismutase activity compared to wild-type seeds after AA treatment. In addition, we showed that NnMT2a and NnMT3 conferred improved germination ability to NaCl and methyl viologen on transgenic Arabidopsis seeds. Taken together, these data demonstrate that overexpression of NnMT2a and NnMT3 in Arabidopsis significantly enhances seed germination vigor after AA treatment and under abiotic stresses. PMID:21971996
Zhou, Yuliang; Chu, Pu; Chen, Huhui; Li, Yin; Liu, Jun; Ding, Yu; Tsang, Edward W T; Jiang, Liwen; Wu, Keqiang; Huang, Shangzhi
Demethylesterification of cell wall pectins in Arabidopsis plays a role in seed germination.
The methylesterification status of cell wall homogalacturonans, mediated through the action of pectin methylesterases (PMEs), influences the biophysical properties of plant cell walls such as elasticity and porosity, important parameters for cell elongation and water uptake. The completion of seed germination requires cell wall extensibility changes in both the radicle itself and in the micropylar tissues surrounding the radicle. In wild-type seeds of Arabidopsis (Arabidopsis thaliana), PME activities peaked around the time of testa rupture but declined just before the completion of germination (endosperm weakening and rupture). We overexpressed an Arabidopsis PME inhibitor to investigate PME involvement in seed germination. Seeds of the resultant lines showed a denser methylesterification status of their cell wall homogalacturonans, but there were no changes in the neutral sugar and uronic acid composition of the cell walls. As compared with wild-type seeds, the PME activities of the overexpressing lines were greatly reduced throughout germination, and the low steady-state levels neither increased nor decreased. The most striking phenotype was a significantly faster rate of germination, which was not connected to altered testa rupture morphology but to alterations of the micropylar endosperm cells, evident by environmental scanning electron microscopy. The transgenic seeds also exhibited an apparent reduced sensitivity to abscisic acid with respect to its inhibitory effects on germination. We speculate that PME activity contributes to the temporal regulation of radicle emergence in endospermic seeds by altering the mechanical properties of the cell walls and thereby the balance between the two opposing forces of radicle elongation and mechanical resistance of the endosperm. PMID:23129203
Müller, Kerstin; Levesque-Tremblay, Gabriel; Bartels, Sebastian; Weitbrecht, Karin; Wormit, Alexandra; Usadel, Bjoern; Haughn, George; Kermode, Allison R
Dynamics of the antioxidant system during seed osmopriming, post-priming germination, and seedling establishment in Spinach (Spinacia oleracea).
Osmopriming is a pre-sowing treatment that improves seed germination performance and stress tolerance. To understand osmopriming physiology, and its association with post-priming stress tolerance, we investigated the antioxidant system dynamics during three stages: during osmopriming, post-priming germination, and seedling establishment. Spinach seeds (Spinacia oleracea L. cv. Bloomsdale) were primed with -0.6 MPa PEG at 15°C for 8 d, and dried at room temperature for 2 d. Unprimed and primed germinating seeds/seedlings were subjected to a chilling and desiccation stresses. Seed/seedling samples were collected for antioxidant assays and germination performance and stress tolerance were evaluated. Our data indicate that: (1) during osmopriming the transition of seeds from dry to germinating state represses the antioxidant pathways (residing in dry seeds) that involve CAT and SOD enzymes but stimulates another pathway (only detectable in imbibed seeds) involving APX; (2) a renewal of antioxidant system, possibly required by seedling establishment, occurs after roughly 5 d of germination; (3) osmopriming strengthens the antioxidant system and increases seed germination potential, resulting in an increased stress tolerance in germinating seeds. Osmopriming-mediated promotive effect on stress tolerance, however, may diminish in relatively older (e.g. ~5-week) seedlings. PMID:21421363
Chen, Keting; Arora, Rajeev
Heat shock, mass-dependent germination, and seed yield as related components of fitness in Cistus ladanifer.
The different weight-number strategies of seed production displayed by individuals of a Mediterranean fire-prone plant species (Cistus ladanifer) were investigated in relation to seed germination responses to pre-germination heating. A control (no heating), a high temperature during a short exposure time (100 degrees C during 5 min) and a high temperature during a long exposure time (100 degrees C during 15 min) were applied to seeds from different individual plants with different mean seed weight. These pre-germination treatments resemble natural germination scenarios for the studied species, absence of fire, typical Mediterranean shrub fire, and severe fire with high fuel load. Seed germination was related to heat treatments and seed mass. Seed heating increased the proportion of seeds germinating compared with the control treatment. Mean seed weight was positively correlated to the proportion of germinated seeds but only within heat treatments. These results suggest that in periods without fire, the relative contributions to the population dynamics are equal for all seeds, regardless of their mass, whereas heavier seeds would be the main contribution after wildfire events. Since lighter seeds can be produced in higher quantities than heavier ones within a given fruit, the number of seedlings produced per fruit depended strongly on the germination conditions. In the absence of wildfire, fruits producing lighter seeds gave rise to more seedlings; nevertheless, they were numerically exceeded by those producing heavy seeds after a wildfire. The implications of these results are discussed in relation to their consequences on the population dynamics of this species, considering also additional information on stand flammability and changes in seed mass with plant age. PMID:11378168
Delgado, J A.; Serrano, J M.; López, F; Acosta, F J.
Effect of stand age and individual growth on seed germination of Populus euphratica in the Ejina Oasis, China
We conducted an investigation into the germination of seeds from individual Populus euphratica trees of different ages and growing conditions in order to discover the effect of intraspecific factors on their sexual reproduction\\u000a in the Ejina Oasis, Inner Mongolia of China. By carrying out germination experiments of seeds collected at various seed dispersal\\u000a periods, we found that P. euphratica seeds
Qian-wen Liu; Peng Hao; Jing-wen Li; Zhi-gang Tan; Amugulang; Jing-yu Luo
Arabidopsis Cytokinin Receptor Mutants Reveal Functions in Shoot Growth, Leaf Senescence, Seed Size, Germination, Root Development, and Cytokinin Metabolism
We used loss-of-function mutants to study three Arabidopsis thaliana sensor histidine kinases, AHK2, AHK3, and CRE1\\/ AHK4, known to be cytokinin receptors. Mutant seeds had more rapid germination, reduced requirement for light, and decreased far-red light sensitivity, unraveling cytokinin functions in seed germination control. Triple mutant seeds were more than twice as large as wild-type seeds. Genetic analysis indicated a
Michael Riefler; Ondrej Novak; Miroslav Strnad; Thomas Schmullinga
Promotion of Seed Germination by Nitrate, Nitrite, Hydroxylamine, and Ammonium Salts 1
Action and uptake of azides, nitrates, nitrites, hydroxylamines, and ammonium salts were measured on germination of Amaranthus albus, Lactuca sativa, Phleum pratense, Barbarea vulgaris, B. verna, and Setaria glauca seeds. Nitrate and nitrite reductase activities were measured in vivo for each of these kinds of seeds. Activities were measured in vitro for catalase, peroxidase, glycolate oxidase, and pyridine nucleotide quinone reductase on extracts of A. albus and L. sativa seeds before and after germination. The enzymic activities measured and the responsiveness of the haemproteins to inhibition by the several compounds indicate that nitrites, azides, and hydroxylamines promote seed germination by inhibition of H2O2 decomposition by catalase. Ammonium salts showed pronounced promotive activity only for B. verna and B. vulgaris seeds, for which they served as metabolic substrates. The promotion of germination is thought to depend on coupling of peroxidase action to NADPH oxidation, which can regulate the pentose pathway of d-glucose 6-phosphate use. Pyridine nucleotide quinone reductase is the possible coupling enzyme. This enzyme and others required for the action are present in the seeds before imbibition of water.
Hendricks, S. B.; Taylorson, R. B.
Long distance dispersal may have important consequences for gene flow and community structure. The dispersal of many plants\\u000a depends on transport by vertebrate seed dispersers. The shapes of seed shadows produced by vertebrates depend both on movement\\u000a patterns of the dispersers and on the dynamics and effects of passage through the disperser's gut (i.e. the retention time,\\u000a survival and germination
Jordi Figuerola; Iris Charalambidou; Luis Santamaria; Andy J. Green
Proline Metabolism and Cross-Tolerance to Salinity and Heat Stress in Germinating Wheat Seeds
Germination\\/growth of wheat (Triticum aestivum L., cv. Zimai 1) seeds and changes in the levels of proline and protein as well as in activities of key enzymes involved\\u000a in proline metabolism in response to salinity-, heat-stresses and their cross-stress were studied. With decreasing water potential\\u000a caused by increasing concentrations of NaCl, germination percentage, fresh weight of seedlings and protein amount
S. Q. Song; Y. B. Lei; X. R. Tian
Seed germination and salinity tolerance in plant species growing on saline wastelands
Seven plant species including three chenopods:Suaeda fruticosa, Kochia indica, Atriplex crassifolia and four grasses:Sporobolus arabicus, Cynodon dactylon, Polypogon monspeliensis, Desmostachya bipinnata, varied greatly in their seed germination and growth responses to soil moisture or salinity. The germination percentage of\\u000a each species was significantly lower at soil moisture level of 25 % of water holding capacity than at the levels ranging
K. Mahmood; K. A. Malik; M. A. K. Lodhi; K. H. Sheikh
Differential sensitivity to cadmium in germinating seeds of three cultivars of faba bean ( Vicia faba L.)
The reserve mobilization was analysed in germinating seeds of faba bean (Vicia faba) exposed to treatment with a toxic cadmium concentration for 4 days. When the behaviours of three cultivars were compared\\u000a with regard to the germination rate, the following order of sensitivity to cadmium was observed: Aguadulce and Luz de otońo\\u000a showed 59 and 19% of inhibition from controls, respectively,
Sondčs Rahoui; Abdelilah Chaoui; Ezzeddine El Ferjani
Seed Germination in Relation to Salinity and Temperature in Sarcobatus Vermiculatus
Sarcobatus vermiculatus (Hook) Torrey is a leaf succulent, sodium-accumulating shrub usually found in saline substrates of the Great Basin desert, Utah, USA. Laboratory experiments were conducted to determine the effect of salinity (0, 200, 400, 600, 800 and 1000 mM NaCl) and temperature (day\\/night: 5\\/15, 10\\/20, 15\\/25, 20\\/30, and 25\\/35°C) on seed germination. S. vermiculatus showed 100% germination in non-saline
M. A. Khan; B. Gul; D. J. Weber
Lead phytotoxicity on wheat ( Triticum aestivum L.) seed germination and seedlings growth
Lead (Pb) is an environmental pollutant extremely toxic to plants and other living organisms including humans. To assess Pb phytotoxicity, experiments focusing on germination of wheat seeds were germinated in a solution containing Pb (NO3)2 (0.05; 0.1; 0.5; 1g\\/L) during 6 days. Lead accumulation in seedlings was positively correlated with the external concentrations, and negatively correlated with morphological parameters of plant
Mostafa Lamhamdi; Ahmed Bakrim; Ahmed Aarab; René Lafont; Fouad Sayah
Protein Synthesis in Embryos of Dormant and Germinating Agrostemma githago L. seeds
The time course of protein synthesis in embryos of dormant and afterripened Agrostemma githago seeds was studied. In embryos of afterripened geminating seeds, protein synthesis increased in three successive stages: (a) concurrent with swelling; (b) during the lag phase between the completion of water uptake and the onset of growth; and (c) immediately after protrusion through the seed coat. Embryos of dormant seeds showed the first increase but not the second unless dormancy was broken by imbibition at 4°C. This indicates that dormancy affects processes prior to the onset of growth. The third increase was largely due to higher oxygen availability after the rupture of the seed coat and not to actual growth. It could also be elicited in dormant embryos by isolating them from the seeds. Electrophoretic analysis of the newly synthesized proteins demonstrated that the patterns of dormant and afterripened embryos became significantly different in both axes and cotyledons only just prior to the onset of axis elongation. Thereafter, the differences became larger. When afterripened or dormant seeds were transferred from a low, germination-permitting to a high, germination-inhibiting temperature, the seeds germinated at the high temperature if they had completed the lag phase to a sufficient extent at the low temperature. This shows that the processes during the lag phase were inhibited by the high temperature while the onset of growth was not affected.
de Klerk, Geert Jan; Smulders, Rene
In vitro seed germination of economically important edible bamboo Dendrocalamus membranaceus Munro.
An in vitro propagation protocol using mature seeds of D. membranaceus was successfully established. Scarcity of seeds in bamboos because of their long flowering periods and irregular seed set resulting in low viability and germination potential, motivated us to undertake the present study. The effects of sterilants, light conditions, exogenous application of plant growth regulators and temperature in overcoming germination barriers in ageing seeds of bamboo were studied. It was found that HgCl2 (0.1%) along with bleach (15%) was more effective in raising aseptic cultures. Dark conditions, high temperatures around 30 degrees C and soaking of seeds in GA3 solution (50 ppm) overnight stimulated high percent of seed germination with corresponding increase in shoot length (2.7 +/- 0.7 mm) and number of sprouts (2.1 +/- 0.7) per explants during culture initiation. 6-benzylaminopurine acted synergistically with kinetin to give optimum germination rate of 70 +/- 13.9% as compared to 63.13% when used individually. For prolonged maintenance of cultures, 2% sucrose was found to be suitable for promoting photomixotrophic micropropagation. Following this procedure, about 65% survival of plantlets could be achieved during hardening. Biochemically seeds consume starchy endosperm for emergence of radicle which is taken as a sign of germination as also evident from the present study. Loss of viability and vigour after a year was confirmed by Tetrazolium chloride test. Micropropagation protocol developed here will ensure regeneration of large number of plants in a relatively short time. Conclusively, in vitro propagation protocol developed in D. membranaceus using mature seeds as an explants is reported for the first time. PMID:23441484
Brar, Jasmine; Anand, Manju; Sood, Anil
Rhizonin A from Burkholderia sp. KCTC11096 and its growth promoting role in lettuce seed germination.
We isolated and identified a gibberellin-producing Burkholderia sp. KCTC 11096 from agricultural field soils. The culture filtrate of plant growth promoting rhizobacteria (PGPR) significantly increased the germination and growth of lettuce and Chinese cabbage seeds. The ethyl acetate extract of the PGPR culture showed significantly higher rate of lettuce seed germination and growth as compared to the distilled water treated control. The ethyl acetate fraction of the Burkholderia sp. was subjected to bioassay-guided isolation and we obtained for the first time from a Burkholderia sp. the plant growth promoting compound rhizonin A (1), which was characterized through NMR and MS techniques. Application of various concentrations of 1 significantly promoted the lettuce seed germination as compared to control. PMID:22759911
Kang, Sang-Mo; Khan, Abdul Latif; Hussain, Javid; Ali, Liaqat; Kamran, Muhammad; Waqas, Muhammad; Lee, In-Jung
[A comparative study on seed germination of 15 grass species in Keeqin Sandyland].
A laboratory study was made on the germination characteristics of freshly-collected seeds of grass species at the Wulanaodu area of Keeqin Sandyland in Eastern Inner-Mongolia. Of the 15 species examined, 8 species including Clinelymus dahuricus, Cleistogenes squarrosa, Pappophorum boreale, Spodiopogon sibiricus, Phragmites communis, Chloris virgata, Arundinella hirta, Pennisetum alopecuroides had a germination rate of over 80%, but 4 species including Echinochloa hispidula, Hemarthria compressa, Tragus berteronianus and Setaria viridis had a value of less than 10%. Spodiopogon sibiricus, Eragrostis pilosa, Phragmites communis, Chloris virgata, Clinelymus dahuricus, Pappophorum boreale, Digitaria cilliaris and Cleistogenes squrrosa began to germinate within 1-3 days after the test began, while Setaria viridis, Tragus berteronianus and Hemarthria compressa failed to germinate in a period of more than 10 days. For the species such as Digitaria cilliaris, Echinochloa hispidula, Phragmites communis, Eragrostis pilosa and Spodiopogon sibiricus, their germination period was less than 10 days, while Clinelymus dahuricus and Pappophorum boreale had a germination period of more than 20 days. The days required for half the final germination rate to be reached were: 2 days for Chloris virgata, 3 days for Phragmites communis, 4 days for Spodiopogon sibiricus, 5 days for Clinelymus dahuricus and Cleistogenes squarrosa, 7 days for Arundinella hirta and Pappophorum boreale, and 10 days for Pennisetum alopecuriodes. Compared with the Sheffield region in Britain, the Wulanaodu area of Kerqin Sandyland had a higher proportion of annul grasses with a low germination rate and a longer germination period, and the perennial grasses at the Wulanaodu area had an approximately same germination rate, but a longer germination period. During germination, ruderals showed the potential for risk-sharring, and thus, they had a relatively higher disturbance-resistance capacity. PMID:14732991
Liu, Zhimin; Li, Xuehua; Li, Rongping; Jiang, Deming; Cao, Chengyou
Proteases in germinating finger millet ( Eleusine coracana ) seeds
Proteolytic activity was estimated in germinated finger millet seedlings using the endogenous trypsin\\/amylase inhibitor as\\u000a substrate and also with haemoglobin and albumin as substrates. The maximal proteolytic activity was observed on the third\\u000a day of germination. With the inhibitor as substrate, the proteolytic activity was maximal at pH 2.5. The protease that acted\\u000a on the inhibitor required sulphydryl groups for
U. Vidyavathi; B. Shivaraj; T. N. Pattabiraman
TaMFT-A1 Is Associated with Seed Germination Sensitive to Temperature in Winter Wheat
The ability of seed to germinate under favorable environmental conditions is critical for seedling emergence, plant establishment, subsequent development and growth of adult plants, and it is controlled by internal genetic factors and external environmental factors. Winter wheat in the southern Great Plains is often planted six weeks before the optimal planting date to produce more biomass for cattle grazing during the winter season. A high seed germination rate in this higher soil temperature environment is required for this specific management system. In this study, a major QTL for temperature-sensitive germination was mapped on the short arm of chromosome 3A (QTsg.osu-3A) in a RIL population generated from two winter wheat cultivars. Furthermore, TaMFT-A1, previously reported to regulate seed dormancy and pre-harvest sprouting in spring wheat cultivars, was mapped tightly associated with the peak of QTsg.osu-3A. However, allelic variation in TaMFT-A1 between the two winter wheat cultivars differed from that was observed in spring wheat cultivars. There were 87 SNPs (single nucleotide polymorphisms) and 12 indels (insertions/deletions) in TaMFT-A1 between the Jagger allele for high germination and the 2174 allele for low germination in the after-ripened seeds, in comparison with 2 SNPs between the two alleles for differential pre-harvest sprouting in spring wheat cultivars. The Jagger TaMFT-A1 allele is a novel haplotype and appears extensively in winter wheat cultivars. TaMFT-A1 transcript levels were up-regulated by high temperature but down-regulated by low temperature or seed storage time. These findings suggest that TaMFT-A1 may invoke different mechanisms for controlling seed dormancy/germination among winter wheat cultivars.
Wang, Shuwen; Zhu, Meirong; Carver, Brett F.; Yan, Liuling
TaMFT-A1 Is Associated with Seed Germination Sensitive to Temperature in Winter Wheat.
The ability of seed to germinate under favorable environmental conditions is critical for seedling emergence, plant establishment, subsequent development and growth of adult plants, and it is controlled by internal genetic factors and external environmental factors. Winter wheat in the southern Great Plains is often planted six weeks before the optimal planting date to produce more biomass for cattle grazing during the winter season. A high seed germination rate in this higher soil temperature environment is required for this specific management system. In this study, a major QTL for temperature-sensitive germination was mapped on the short arm of chromosome 3A (QTsg.osu-3A) in a RIL population generated from two winter wheat cultivars. Furthermore, TaMFT-A1, previously reported to regulate seed dormancy and pre-harvest sprouting in spring wheat cultivars, was mapped tightly associated with the peak of QTsg.osu-3A. However, allelic variation in TaMFT-A1 between the two winter wheat cultivars differed from that was observed in spring wheat cultivars. There were 87 SNPs (single nucleotide polymorphisms) and 12 indels (insertions/deletions) in TaMFT-A1 between the Jagger allele for high germination and the 2174 allele for low germination in the after-ripened seeds, in comparison with 2 SNPs between the two alleles for differential pre-harvest sprouting in spring wheat cultivars. The Jagger TaMFT-A1 allele is a novel haplotype and appears extensively in winter wheat cultivars. TaMFT-A1 transcript levels were up-regulated by high temperature but down-regulated by low temperature or seed storage time. These findings suggest that TaMFT-A1 may invoke different mechanisms for controlling seed dormancy/germination among winter wheat cultivars. PMID:24069187
Lei, Lei; Zhu, Xinkai; Wang, Shuwen; Zhu, Meirong; Carver, Brett F; Yan, Liuling
The role of nitric oxide in the germination of plant seeds and pollen.
Two complex physiological processes, with opposite positions in the plant's life-cycle, seed and pollen germination, are vital to the accomplishment of successful plant growth and reproduction. This review summarizes the current state of knowledge of the intersection of NO signalling with the signalling pathways of ABA, GA, and ethylene; plant hormones that control the release of plant seeds from dormancy and germination. The cross-talk of NO and ROS is involved in the light- and hormone-specific regulation of seeds' developmental processes during the initiation of plant ontogenesis. Similarly to seed germination, the mechanisms of plant pollen hydration, germination, tube growth, as well as pollen-stigma recognition are tightly linked to the proper adjustment of NO and ROS levels. The interaction of NO with ROS and secondary messengers such as Ca(2+), cAMP and cGMP discovered in pollen represent a common mechanism of NO signalling. The involvement of NO in both breakpoints of plant physiology, as well as in the germination of spores within fungi and oomycetes, points toward NO as a component of an evolutionary conserved signalling pathway. PMID:21893253
Šírová, Jana; Sedlá?ová, Michaela; Piterková, Jana; Luhová, Lenka; Pet?ivalský, Marek
Effects of fungicide seed treatments on germination, population, and yield of maize grown from seed infected with fungal pathogens
Seedborne fungi can reduce survival, growth, and yield of maize (Zea mays L.). Laboratory, field, and growth chamber experiments were conducted to determine the effects of the seed treatment fungicides fludioxonil, mefenoxam, and azoxystrobin on germination, plant population, and grain yield of maiz...
Effect of Storage Conditions and Storage Periods on Seed Germination in Eleven Populations of Swertia chirayita: A Critically Endangered Medicinal Herb in Himalaya
Effect of different storage conditions (room temperature, 4°C, and ?15°C) and different storage periods over 24 months on seed germination in Swertia chirayita collected from different altitudes in Sikkim Himalaya was determined. Multivariate ANOVA revealed significant (P < 0.0001) effect of storage condition and storage period on seed germination and mean germination time. Seed germination percentage significantly (P < 0.01) varied between 87.78% (Sc5) and 100% (Sc2) during initial testing. Comparatively, high seed germination, low mean germination time, and low rate of fall in seed germination percentage in seeds stored at 4°C over different storage period were recorded. In addition, above 50% seed germination in majority of the populations even after 24 months of storage suggests 4°C as the most appropriate storage condition for long-term storage of seeds of S. chirayita.
Pradhan, Bharat K.; Badola, Hemant K.
Effects of wastewater from olive processing on seed germination and early plant growth of different vegetable species
The effects of wastewater from olive processing on seed germination and early plant growth of different vegetable species were examined. Three types of wastewater at different concentrations were tested: raw wastewater, wastewater with organic matter removed and deionized wastewater.Results generally indicate an inhibitory effect on seed germination and early plant growth by all treatments containing any kind of wastewater. Of
J. D. Perez; E. Esteban; M. Gomez
Relationship of Seed Microsite to Germination and Survival of Lodgepole Pine on High-Elevation Clearcuts in Northeastern Utah.
On two high-elevation sites (3,000 m) in northeastern Utah, lodgepole pine (Pinus contorta var. latifolia) seeds germinated best (53 percent) on large mineral microsites (5 x 5 m), and percentage survival of germinating seeds was best on microsites covere...
D. S. Page-Dumroese R. Kasten Dumroese C. M. Carpenter D. L. Wenny
Arabidopsis ABA INSENSITIVE4 Regulates Lipid Mobilization in the Embryo and Reveals Repression of Seed Germination by the Endosperm
Regulation of seed germination requires coordinate action by the embryo and surrounding endosperm. We used Arabidopsis thaliana to establish the relative roles of embryo and endosperm in the control of seed germination and seedling establishment. We previously showed that endospermic oil reserves are used postgerminatively via gluconeo- genesis to fuel seedling establishment and that lipid breakdown is repressed by abscisic
Steven Penfield; Yi Li; Alison D. Gilday; Stuart Graham; Ian A. Graham
Seed germination ecology of Polymnia canadensis (Asteraceae), a monocarpic species of the North American Temperate Deciduous Forest
The seed germination of Polymnia canadensis was studied in relation to its wide variation in life history and its ecology as a mostly facultative biennial, a life cycle type that is rare in stable forest habitats in eastern North America. The seed dormancy and germination characteristics of P. canadensis were like some other herbaceous woodland species of diverse life cycle
Martin H. Bender; Jerry M. Baskin; Carol C. Baskin
Seed germination and removal of Michelia champaca L. (Magnoliaceae) in eucalypt stands: the influence of the aril
We tested the influence of the aril on seed germination in controlled conditions and on the removal of M. champaca seeds in natural environment. Germination assays were kept at 25 ± 2 °C under continuous white light. Removal experiments were carried out in three \\
Giovano Candiani; Mauro Galetti; Victor Jose Mendes Cardoso
Evidence for the accumulation of a germination inhibitor during progressive thermoinhibition of seeds of celery (Apium graveolens L.)
The germination of seeds of celery (Apium graveolens L.) becomes progressively thermoinhibited on incubation in the dark at high temperatures, the inhibitory temperature being dependent on the cultivar used. In two high-dormancy cultivars of celery, the production of germination inhibitors in seeds incubated in the dark at 26°C gradually increased over a 7-day period. Inhibitor production was measured by incubating
Tudor H. Thomas; Anthony S. Dearman; Norman L. Biddington
Allenrolfea occidentalis, a perennial halophytic shrub in the family Chenopodiaceae is widely distributed in the inland salt marshes and salt playas of western United States. Experiments were conducted to determine the influence of compatible osmotica (betaine and proline) and growth regulators (gibberellic acid and kinetin) in alleviating salinity stress on the seed germination of A. occidentalis. Seed germination decreased with
Alleviation of salt stress-induced inhibition of seed germination in cucumber ( Cucumis sativus L.) by ethylene and glutamate
Ethylene is an important plant gas hormone, and the amino acid Glu is emerging as a messenger molecule in plants. To evaluate the role of ethylene and Glu in seed germination and radicle growth under salt stress, effects of 1-aminocyclopropane-1-carboxylic acid (ACC), Ethephon and Glu on germination and radicle growth of cucumber (Cucumis sativus L.) seeds in the absence and
Chenshuo Chang; Baolan Wang; Lei Shi; Yinxin Li; Lian Duo; Wenhao Zhang
Effect of microorganisms and nitrogen on the allelopathy of sorghum residues and the germination of wheat seeds
This experiment examines the effect of microorganisms on the allelopathic chemicals from sorghum residues on the germination of wheat seeds. Sorghum plants were decomposed to obtain an extract from the residue. This residue was used to germinate wheat seeds at each nitrogen level. The different nitrogen levels did not appear to change the effect that the allelopathic chemicals had on
Terry S. Phillips
Seed germination and seedling growth of Suaeda salsa under salt stress
The effect of increasing concentrations (0, 0.05, 0.1, 0.2, 0.3, 0.4, 0.6 mol l-1) of dif- ferent salts (Na2SO4, Na2CO3, MgSO4, NaCl, MgCl2) in solution and soil extract solu- tions of comparable osmotic potentials on germination of Suaeda salsa seeds was studied. Seed germination decreased significantly with increased salinity. Germina - tion inhibition was in the following order: MgCl2 >
De-Yu Duan; Wei-Qiang Li; Xiao-Jing Liu; Hua Ouyang; Ping An
A comparison of barley malt amylolytic enzyme thermostabilities and 1 wort sugars produced during mashing
The industrial process that converts seed starch to fermentable sugars, known as mashing, takes place at high temperatures. Barley seed is typically germinated for 4 – 6 days during the malting process during which time the enzymes that convert starch to sugars are either synthetized and/or activat...
Loss-of-function of DELLA protein SLN1 activates GA signaling in barley aleurone
Gibberellic acid (GA) is a key phytohormone regulating seed germination and seedling growth. In cereal species, GA is synthesized in embyros and then translocated to aleurone tissues where it induces production of hydrolytic enzymes for mobolization of seed storage reserve. De-embyronated barley a...
Hoarding decisions by Edward's long-tailed rats ( Leopoldamys edwardsi) and South China field mice ( Apodemus draco): The responses to seed size and germination schedule in acorns
Co-varying traits in acorns such as seed size and germination schedule are important to influence the behavioural decisions of hoarding rodents. Using acorn pairs from cork oak (Quercus variabilis) (large size and short germination schedules) serrate oak (Q. serrata) (small size and short germination schedule) and qinggang (Cyclobalanopsis glauca) (small size and long germination schedule) with contrasting seed size and
Gang Chang; Zhishu Xiao; Zhibin Zhang
Effect of germination of legume seeds on chemical composition and on protein and energy utilization in rats
Chemical composition of soybeans, lupin seeds and black beans, and protein utilization and energy digestibility of soybeans and lupin seeds determined in a rat model, were compared before and after a 48-h germination. Black beans had a much higher starch content and lower levels of low-molecular-weight (LMW) sugars than soybeans and lupin seeds. Lupin seeds had about twice as much
C. M. Donangelo; L. C. Trugo; N. M. F. Trugo; B. O. Eggum
Ethylene as a possible cue for seed germination of Schoenoplectus hallii (Cyperaceae), a rare summer annual of occasionally flooded sites
The purpose of our research was to determine why seeds of Schoenoplectus hallii germinate only in some wet years. Seeds mature in autumn, at which time they are dormant. Seeds come out of dormancy during winter, if buried in nonflooded, moist soil, but they remain dormant if buried in flooded soil. Nondormant seeds require flooding, light, and exposure to ethylene
CAROL C. BASKIN; JERRY M. BASKIN; E. W. Chester; MARIAN SMITH
The probability of germination and establishment in discrete density-dependent plant populations with a seed bank: a correction formula
The effect of ignoring a seed bank in unstructured population models of annual plants is investigated under the assumption of ecological equilibrium. It is demonstrated that if delayed germination is an important life-history strategy and seed mortality in the seed bank is relatively low then it is important to take the effect of the seed bank into account. A formula
Christian Damgaard
Microflora of Barley Kernels1
Numbers and kinds of microflora were determined in 160 samples of barley grown in different regions of the United States; microflora were more abundant in the grains grown in the central states than in those grown in the western states. During steeping and germination in micromalting equipment, the number of colonies of filamentous fungi increased from two to five times, colonies of yeasts from five to ten times, and bacteria from 50 to more than 100 times the numbers present in the grain before malting. Kiln drying according to a commercial schedule reduced the number of all types of microflora below the number present before kilning, but all were present in larger numbers in the kilned malt than in the original grain. In barley stored at room temperature and at a moisture content of 15 to 18%, members of the Aspergillus glaucus group increased with increasing time and increasing moisture content, and germination percentage of the seeds decreased. Stored free of storage fungi at room temperature, barley with a moisture content just over 15% retained a high germination percentage for 5 months, but at a moisture content of 16% the germination decreased to zero.
Follstad, M. N.; Christensen, C. M.
Vacuolar H+-ATPase Is Expressed in Response to Gibberellin during Tomato Seed Germination1
Completion of germination (radicle emergence) by gibberellin (GA)-deficient (gib-1) mutant tomato (Lycopersicon esculentum Mill.) seeds is dependent upon exogenous GA, because weakening of the endosperm tissue enclosing the radicle tip requires GA. To investigate genes that may be involved in endosperm weakening or embryo growth, differential cDNA display was used to identify mRNAs differentially expressed in gib-1 seeds imbibed in the presence or absence of GA4+7. Among these was a GA-responsive mRNA encoding the 16-kD hydrophobic subunit c of the V0 membrane sector of vacuolar H+-translocating ATPases (V-ATPase), which we termed LVA-P1. LVA-P1 mRNA expression in gib-1 seeds was dependent on GA and was particularly abundant in the micropylar region prior to radicle emergence. Both GA dependence and tissue localization of LVA-P1 mRNA expression were confirmed directly in individual gib-1 seeds using tissue printing. LVA-P1 mRNA was also expressed in wild-type seeds during development and germination, independent of exogenous GA. Specific antisera detected protein subunits A and B of the cytoplasmic V1 sector of the V-ATPase holoenzyme complex in gib-1 seeds only in the presence of GA, and expression was localized to the micropylar region. The results suggest that V-ATPase plays a role in GA-regulated germination of tomato seeds.
Cooley, Michael B.; Yang, Hong; Dahal, Peetambar; Mella, R. Alejandra; Downie, A. Bruce; Haigh, Anthony M.; Bradford, Kent J.
Factors influencing seed germination of Salsola affinis (Chenopodiaceae), a dominant annual halophyte inhabiting the deserts of Xinjiang, China
Salsola affinis is a dominant annual inhabiting saline deserts of Xinjiang, China. Experiments were conducted to determine the effects of temperature, winged perianths and NaCl on seed germination and on germination recovery from the effects of saline conditions after transfer to distilled water. Freshly harvested seeds could germinate equally well in light and darkness at 5–30°C. Attached winged perianths significantly
Yan Wei; Ming Dong; Zhen-ying Huang; Dun-yan Tan
Influence of temperature and watering frequencies on seed germination and seedling growth of Ornithogalum longibracteatum and Tulbaghia violacea
The effect of temperature and watering frequencies on seedling growth were investigated in Ornithogalum longibracteatum and Tulbaghia violacea. Temperature had a significant influence on seed germination with low (10°C) and high (40°C) temperatures resulting in poor germination in both species. The optimum temperature for seed germination of O. longibracteatum and T. violacea was 22.9 and 26.8°C, respectively. Seedling survival rate
M. G. Kulkarni; S. G. Sparg; J. van Staden
Roles of Soluble Sugars in Protecting Phytochrome and Gibberellin A 3 -Mediated Germination Control in Skotodormant Lettuce Seeds
. Skotodormant seeds of Lactuca sativa Grand Rapids imbibed in darkness for 10 days (10-day DS) germinated poorly upon terminal treatment with red light (R) or\\u000a gibberellin A3 (GA3). Soluble sugars in the imbibition solutions influenced the depth of skotodormancy. Ten-day DS seeds, imbibed in 50–500 mm sucrose or 100–500 mm glucose and given terminal GA3 germinated completely and germinated
A. I. Hsiao; W. A. Quick
Seed size and germination response: a relationship for fire-following plant species exposed to thermal shock
Thermal shock is well known to be an important stimulus for the germination of soil-stored seeds in fire-prone plant communities. Nevertheless, while the overall germination response of different species is known to vary, the interaction between seed size and germination to a range of thermal-shock temperatures is poorly understood. This interaction may be important in regulating post-fire plant community establishment,
M. E. Hanley; J. E. Unna; B. Darvill
Enhancement of Salinity Tolerance during Rice Seed Germination by Presoaking with Hemoglobin
Salinity stress is an important environmental constraint limiting the productivity of many crops worldwide. In this report, experiments were conducted to investigate the effects of seed presoaking by bovine hemoglobin, an inducer of heme oxygenase-1 (HO-1), on salinity tolerance in rice (Oryza sativa) plants. The results showed that different concentrations of the hemoglobin (0.01, 0.05, 0.2, 1.0, and 5.0 g/L) differentially alleviated the inhibition of rice seed germination and thereafter seedling shoot growth caused by 100 mM NaCl stress, and the responses of 1.0 g/L hemoglobin was the most obvious. Further analyses showed that application of hemoglobin not only increased the HO-1 gene expression, but also differentially induced catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) activities or transcripts, thus decreasing the lipid peroxidation in germinating rice seeds subjected to salt stress. Compared with non-hemoglobin treatment, hemoglobin presoaking also increased the potassium (K) to sodium (Na) ratio both in the root and shoot parts after salinity stress. The effect is specific for HO-1 since the potent HO-1 inhibitor zinc protoporphyrin IX (ZnPPIX) blocked the positive actions of hemoglobin on seed germination and seedling shoot growth. Overall, these results suggested that hemoglobin performs an advantageous role in enhancement of salinity tolerance during rice seed germination.
Xu, Sheng; Hu, Bing; He, Ziyi; Ma, Fei; Feng, Jianfei; Shen, Wenbiao; Yang, Jie
Enhancement of Salinity Tolerance during Rice Seed Germination by Presoaking with Hemoglobin.
Salinity stress is an important environmental constraint limiting the productivity of many crops worldwide. In this report, experiments were conducted to investigate the effects of seed presoaking by bovine hemoglobin, an inducer of heme oxygenase-1 (HO-1), on salinity tolerance in rice (Oryza sativa) plants. The results showed that different concentrations of the hemoglobin (0.01, 0.05, 0.2, 1.0, and 5.0 g/L) differentially alleviated the inhibition of rice seed germination and thereafter seedling shoot growth caused by 100 mM NaCl stress, and the responses of 1.0 g/L hemoglobin was the most obvious. Further analyses showed that application of hemoglobin not only increased the HO-1 gene expression, but also differentially induced catalase (CAT), ascorbate peroxidase (APX), and superoxide dismutase (SOD) activities or transcripts, thus decreasing the lipid peroxidation in germinating rice seeds subjected to salt stress. Compared with non-hemoglobin treatment, hemoglobin presoaking also increased the potassium (K) to sodium (Na) ratio both in the root and shoot parts after salinity stress. The effect is specific for HO-1 since the potent HO-1 inhibitor zinc protoporphyrin IX (ZnPPIX) blocked the positive actions of hemoglobin on seed germination and seedling shoot growth. Overall, these results suggested that hemoglobin performs an advantageous role in enhancement of salinity tolerance during rice seed germination. PMID:21731454
Effects of ascorbic acid and sodium azide on seedling growth of irradiated and non-irradiated barley seeds
Experiments were designed to test the influence of a radioprotective ; agent (ascorbic acid) and an agent that enhances radiation damage (sodium azide) ; on gamma -radiation induced seedling growth reduction in barley seeds. It was ; found that ascorbic acid protects against radiation-induced damage when given as ; a pre-irradiation treatment but not as a post-irradiation treatment. Sodium ;
[Studies on the effects of fungi on the course of seed germination of Dendrobium lohohens and Dendrobium candidum].
This paper reports the results of studies on the effects of fungi isolated from the protocorms of Orchidaceae on the course of seed germination of D. lohohens and D. candidum. The experiments revealed that these fungi could promote seed germination: the seed germination rate of D. lohohens was 20%, that of D. candidum was 64%, and that of control was zero. The changes of cell ultrastructure in the course of fungus-infected seed germination of D. candidum was also studied. After hyphae of M. osmundicola penetrate the embryo from the suspensor, organelles of embryonic cells infected with fungi will disappear. When the hyphae wall is thickened and enclosed by the embryo's, the hyphae will be digested and used as the source of nutrition for seed germination. Also, the metabolism of cells without infection, but adjacent to those cells penetrated by hyphae is enhanced. PMID:1831700
Guo, S
Barley hordothionin accumulates in transgenic oat seeds and purified protein retains anti-fungal properties in vitro
Summary Transgenic anti-fungal gene expression in heterologous species provides a means to test resistance protein combinations across\\u000a species barriers. This is the first report of transgenic anti-fungal seed storage protein accumulation in oat seed. An anti-fungal\\u000a barley (Hordeum vulgare L.) hordothionin (Hthl) gene was genetically engineered into oat (Avena sativa L.) to determine the effect of hordothionin on pathogen resistance. The
Alvar Carlson; Ron Skadsen; Heidi F. Kaeppler
Imbibition Period as the Critical Temperature Sensitive Stage in Germination of Lima Bean Seeds
Lima bean seeds (Phaseolus lunatus L.) and excised embryonic axes can be injured during imbibition at temperatures below 25°. The early imbibitional stage is critical; imbibition at 25° followed by low temperature exposure does not cause injury. Sensitivity to chilling injury is conditioned by the pre-harvest seed history. Low vigor (bleached) seeds are most sensitive to injury, the effects of which can be intensified by restricted oxygen supply during early axis growth. The seed coat, by preventing water uptake, can permit the seed to avoid injury. This protective mechanism is most effective at low temperature and high moisture stress. Immediately following low temperature imbibition, injured axes lose organic materials, probably nucleotides. This organic leachate is a potential influence on soil microorganisms and, together with the temperature sensitivity, vigor, and seed coat effect undoubtedly is important in controlling the potential variability in germination shown by a seed population. Images
Pollock, B. M.; Toole, Vivian K.
Imbibition period as the critical temperature sensitive stage in germination of lima bean seeds.
Lima bean seeds (Phaseolus lunatus L.) and excised embryonic axes can be injured during imbibition at temperatures below 25 degrees . The early imbibitional stage is critical; imbibition at 25 degrees followed by low temperature exposure does not cause injury. Sensitivity to chilling injury is conditioned by the pre-harvest seed history. Low vigor (bleached) seeds are most sensitive to injury, the effects of which can be intensified by restricted oxygen supply during early axis growth. The seed coat, by preventing water uptake, can permit the seed to avoid injury. This protective mechanism is most effective at low temperature and high moisture stress. Immediately following low temperature imbibition, injured axes lose organic materials, probably nucleotides. This organic leachate is a potential influence on soil microorganisms and, together with the temperature sensitivity, vigor, and seed coat effect undoubtedly is important in controlling the potential variability in germination shown by a seed population. PMID:16656243
Pollock, B M; Toole, V K
Seed borne nature of Azotobacter chroococcum in chilli (Capsicum annum) and its role in seed germination and plant growth.
Investigations were carried out on seed borne nature of Azotobacter chroococcum in chilli and their role in plant growth at the Department of Agriculture Microbiology, University of Agricultural Sciences, Dharwad. Azotobacter chroococcum were isolated from both surface sterilized and unsterilized seeds of 14 varieties of chilli at different stages of fruit maturity. Inoculation with these strains increased the seed germination, root, shoot length and total dry matter content of chilli plants significantly in both sterilized and unsterilized soil., the results of which are presented. PMID:16961202
Bhat, J M; Alagawadi, A R
Proteome Analysis of Grain Filling and Seed Maturation in Barley1
In monocotyledonous plants, the process of seed development involves the deposition of reserves in the starchy endosperm and development of the embryo and aleurone layer. The final stages of seed development are accompanied by an increase in desiccation tolerance and drying out of the mature seed. We have used two-dimensional gel electrophoresis for a time-resolved study of the changes in proteins that occur during seed development in barley (Hordeum vulgare). About 1,000 low-salt extractable protein spots could be resolved on the two-dimensional gels. Protein spots were divided into six categories according to the timing of appearance or disappearance during the 5-week period of comparison. Nineteen different proteins or protein fragments in 36 selected spots were identified by matrix-assisted laser-desorption ionization time of flight mass spectrometry (MS) or nano-electrospray tandem MS/MS. Some proteins were present throughout development (for example, cytosolic malate dehydrogenase), whereas others were associated with the early grain filling (ascorbate peroxidase) or desiccation (Cor14b) stages. Most noticeably, the development process is characterized by an accumulation of low-Mr ?-amylase/trypsin inhibitors, serine protease inhibitors, and enzymes involved in protection against oxidative stress. We present examples of proteins not previously experimentally observed, differential extractability of thiol-bound proteins, and possible allele-specific spot variation. Our results both confirm and expand on knowledge gained from previous analyses of individual proteins involved in grain filling and maturation.
Finnie, Christine; Melchior, Sabrina; Roepstorff, Peter; Svensson, Birte
Cold radiofrequency plasma treatment modifies wettability and germination speed of plant seeds.
We report the possibility to modify the wetting properties of the surfaces of a diversity of seeds including: lentils (Lens culinaris), beans (Phaseolus vulgaris) and wheat (Triticum, species C9) by cold radiofrequency air plasma treatment. Air plasma treatment leads to the dramatic decrease in the apparent contact angle. Moreover, the speed of germination and yield (germination rate) of seeds can be modified by preliminary plasma treatment. The change in the wetting properties of seeds is at least partially due to oxidation of their surface under plasma treatment. Significant growth of the peaks corresponding to the nitrogen containing groups in the mass spectra of air plasma treated seeds was registered by TOF-SIMS spectroscopy. PMID:23077725
Bormashenko, Edward; Grynyov, Roman; Bormashenko, Yelena; Drori, Elyashiv
Cold Radiofrequency Plasma Treatment Modifies Wettability and Germination Speed of Plant Seeds
We report the possibility to modify the wetting properties of the surfaces of a diversity of seeds including: lentils (Lens culinaris), beans (Phaseolus vulgaris) and wheat (Triticum, species C9) by cold radiofrequency air plasma treatment. Air plasma treatment leads to the dramatic decrease in the apparent contact angle. Moreover, the speed of germination and yield (germination rate) of seeds can be modified by preliminary plasma treatment. The change in the wetting properties of seeds is at least partially due to oxidation of their surface under plasma treatment. Significant growth of the peaks corresponding to the nitrogen containing groups in the mass spectra of air plasma treated seeds was registered by TOF-SIMS spectroscopy.
Lettuce seed germination: modulation of pregermination protein synthesis by gibberellic Acid, abscisic Acid, and cytokinin.
Protein synthesis in gibberellin-treated lettuce (Lactuca sativa) seeds has been studied during the lag phase between the beginning of imbibition and the first signs of radicle protrusion. When compared to the water-imbibed controls, both polyribosome populations and radioactive leucine incorporation into protein increase in the embryos of GA(3)- induced seeds early in the imbibition period. Since these results are contradictory to previously published studies, the reasons for the differences are outlined and various alternative possibilities eliminated. The protocol for protein extraction, particularly the speed at which the supernatant from the seed homogenate is cleared, is important for demonstrating the GA(3)-mediated changes. Embryos maintained in the dormant state by abscisic acid still conduct considerable amounts of protein synthesis, and this is enhanced by concentrations of 6-benzylaminopurine which also promote germination. Therefore, the actions of GA(3), abscisic acid, and cytokinin on lettuce seed germination are mediated, directly or indirectly, via protein synthesis. PMID:16659711
Fountain, D W; Bewley, J D
Seed dormancy-breaking and germination requirements of Drosera anglica, an insectivorous species of the Northern Hemisphere
Seeds of Drosera anglica collected in Sweden were dormant at maturity in late summer, and dormancy break occurred during cold stratification. Stratified seeds required light for germination, but light had to be given after temperatures were high enough to be favorable for germination. Seeds stratified in darkness at 5/1 °C and incubated in light at 12/12 h daily temperature regimes of 15/6, 20/10 and 25/15 °C germinated slower and to a significantly lower percentage at each temperature regime than those stratified in light and incubated in light. Length of the stratification period required before seeds would germinate to high percentages depended on (1) whether seeds were in light or in darkness during stratification and during the subsequent incubation period, and (2) the temperature regime during incubation. Seeds collected in 1999 germinated to 4, 24 and 92 % in light at 15/6, 20/10 and 25/15 °C, respectively, after 2 weeks of stratification in light. Seeds stratified in light for 18 weeks and incubated in light at 15/6, 20/10 and 25/15 °C germinated to 87, 95 and 100 %, respectively, while those stratified in darkness for 18 weeks and incubated in light germinated to 6, 82 and 91 %, respectively. Seeds collected from the same site in 1998 and 1999, stratified in light at 5/1 °C and incubated in light at 15/6 °C germinated to 22 and 87 %, respectively, indicating year-to-year variation in degree of dormancy. As dormancy break occurred, the minimum temperature for germination decreased. Thus, seed dormancy is broken in nature by cold stratification during winter, and by spring, seeds are capable of germinating at low habitat temperatures, if they are exposed to light.
Baskin, Carol C.; Milberg, Per; Andersson, Lars; Baskin, Jerry M.
TEMPERA TURA E SUBSTRA TO PARA O TESTE DE GERMINAÇĂO DE SEMENTES DE PINHĂO-MANSO Temperature and substrate for the germination test of physic nut seeds
Official rules for seed analysis don t establish criteria to execute germination tests for all species. This way, the aim of this research was to determinate the substrate, temperature and counting time for the germination test of physic nut seeds. For the germination test, four replications of 20 seeds were used, evaluating daily the normal seedlings until the end of
Cibele Chalita Martins; Carla Gomes Machado; Raquel Cavasini
Mechanical Resistance of the Seed Coat and Endosperm during Germination of Capsicum annuum at Low Temperature 1
Decoated pepper (Capsicum annuum L. cv Early Calwonder) seeds germinated earlier at 25°C, but not at 15°C, compared to coated seeds. The seed coat did not appear to impose a mechanical restriction on pepper seed germination. Scarification of the endosperm material directly in front of the radicle reduced the time to germination at both 15°C and 25°C. The amount of mechanical resistance imposed by the endosperm on radicle emergence before germination was measured using the Instron Universal Testing Machine. Endosperm strength decreased as imbibition time increased. The puncture force decreased faster when seeds were imbibed at 25°C than at 15°C. The reduction in puncture force corresponded with the ability of pepper seeds to germinate. Most radicle emergence occurred at 15°C and 25°C after the puncture force was reduced to between 0.3 and 0.4 newtons. Application of gibberellic acid4+7 (100 microliters per liter) resulted in earlier germination at 15°C and 25°C and decreased endosperm strength sooner than in untreated seeds. Similarly, high O2 concentrations had similar effects on germination earliness and endosperm strength decline as did gibberellic acid4+7, but only at 25°C. At 15°C, high O2 concentrations slowed germination and endosperm strength decline. Images Fig. 1
Watkins, James T.; Cantliffe, Daniel J.
Seed germination conditions and implications for establishment of an epiphyte, Aechmea bracteata (Bromeliaceae)
Aechmea bracteata is a common epiphytic bromeliad found in symbiosis with many other species throughout tropical forests of Mexico and south\\u000a through Panama. Given its importance and distribution in these forests, we asked how may A. bracteata be restored to areas where they have thrived in the past? We first investigated seed viability and response of seed germination\\u000a to temperature,
Laurel K. Goode; Michael F. Allen
Soluble Sugar Contents, Germination, and Vigor of Soybean Seeds in Response to Drought Stress
A greenhouse experiment was conducted to study the effect of drought stress on seed germination and vigor of soybean in relation with soluble sugars. Three drought stress treatments, well-watered treatment (WW), gradual stress (GS) imposed prior to severe stress treatment, and sudden severe stress (SS), were imposed on soybean plants at beginning seed fill stage (R5) for 20–23 d. Drought
N. H. Samarah; R. E. Mullen; I. Anderson
Effects of pre-sowing treatments on seed germination of Melia azedarach
A germination experiment of pre-treated seeds of Melia azedarach was conducted in the nursery of Forestry and Wood Technology Discipline, Khulna University, Bangladesh. Matured seeds of\\u000a Melia azedarach were collected from healthy trees of National Botanical Garden, Bangladesh and were treated with five pre-sowing treatments\\u000a (control, immersion in cold water, immersion in hot water, scarification with sand paper, and immersion
Seed germination techniques of Phoenix dactylifera : A new experience from Bangladesh
A new experiment on seed germination technique for Phoenix dactylifera, an exotic species was conducted in the nursery of Forestry and Wood Technology Discipline, Khulna University, Bangladesh.\\u000a The seeds imported from Saudi Arabia were collected from Nirala Central Mosque, Khulna, Bangladesh, in September 2008 and\\u000a treated with four presowing treatments (control, immersion in normal water at room temperature (20–22°C) for
Digital imaging information technology applied to seed germination testing. A review
The application of digital imaging information technology to seed germination testing is discussed. This technology is reviewed\\u000a in light of recent interest on the development and adoption of sustainable agrosystems joined with a modern strategy of "precision\\u000a agriculture", which provides new complex information tools for better crop production. Basic concepts on the patterns of image\\u000a analysis descriptors of imbibing seed
Antonio Dell' Aquila
Digital Imaging Information Technology Applied to Seed Germination Testing: A Review
Spatially regulated genes expressed during seed germination and postgerminative development are activated during embryogeny
We investigated the control of genes expressed primarily during seed germination and postgerminative development in Brassica napus L. We identified cloned mRNA sequences which became prevalent within 1 day after the start of imbibition and were at low or undetectable levels in immature embryos, dry seeds, and leaves. Most postgermination-abundant mRNAs accumulated primarily, though not exclusively, in different parts of
John J. Harada; Catherine S. Baden; Lucio Comai
Agrobacterium -mediated transformation of germinating seeds of Arabidopsis thaliana : A non-tissue culture approach
Germinating seeds of Arabidopsis thaliana were cocultivated with an Agrobacterium tumefaciens strain (C58Clrif) carrying the pGV3850:pAK1003 Ti plasmid. This Ti plasmid contains the neomycin phosphotransferase II gene (NPT II) which confers resistance to kanamycin and G418. Seeds (T1 generation) imbibed for 12 h before a 24 h exposure to Agrobacterium gave rise to the highest number of transformed progeny (T2
Kenneth A. Feldmann; M. David Marks
Seed germination of two cattail ( Typha ) species as A function of Everglandes nutrient levels
Sawgrass (Cladium jamaicense) is being replaced by cattails (Typha domingensis andTypha latifolia) in Water Conservation Area 2A (WCA 2A) of the Florida Everglades. This replacement coincides with changes in nutrients in\\u000a WCA 2A. Investigating seed germination ofTypha in response to different nutrient levels, focusing on phosphate, might help in understanding how this replacement occurs.\\u000a Three sets of experiments with seed
Herbert Stewart; Shi Li Miao; Marsha Colbert; Charles E. Carraher
Changes in phospholipase D experession in soybeans during seed development and germination
Activation of phospholipase D (PLD) has been linked to accumulation of nonhydratable phosphatides and lipid degradation leading\\u000a to soybean seed deterioration during preharvest and postharvest events. This study examined the changes in PLD activity, protein,\\u000a and mRNA in soybeans during seed development and germination. RNA blotting analysis indicated that expression of the gene\\u000a that encodes PLD was highest during the
Stephen B. Ryu; Ling Zheng; Xuemin Wang
The objective of this work was to evaluate the effects of Stimulate® (0.009 % of citocinine, 0.005 % of gibberelic acid, 0.005 % of indolbutyric acid, and 99.98 % of inert ingredients) applied to seeds, on seed germination, seedling vigor and initial growth of cotton plants, cv BRS 201. Rates of 3.5; 7.0; 10.5; 14.0; 17.5 and 21.0 mL of
Caio Márcio; Guimarăes Santos; Elvis Lima Vieira
The Effect of 5OH-1,4-Naphthoquinone on Norway Spruce Seeds during Germination 1
The effect of 5-OH-1,4-naphthoquinone (5OH-NQ), a known inhibitor of germination and growth and an inducer of oxidative stress, on seeds from Norway spruce (Picea abies) during germination was studied. 5OH-NQ was activated by homogenate from seeds to reactive species that reduce oxygen to superoxide radicals in vitro. Increasing concentrations of 5OH-NQ increased lipid peroxidation during this activation. Small effects of 5OH-NQ on germination of seeds were observed at concentrations up to 200 ?m. However, higher concentrations, e.g. 500 and 1000 ?m, exerted more pronounced effects on seeds. These results suggest that the effect of 5OH-NQ was a delay rather than an inhibition of germination. However, the effect of 5OH-NQ on postgerminative growth was more potent than that on germination, and higher concentrations inhibited growth >97%. These results suggest that the seeds have a very effective defense system against quinone and reactive oxygen species, since the small effects of 5OH-NQ on germination and postgermination at concentrations up to 200 ?m can be explained by the formation of a metabolite of 5OH-NQ that is not as reactive with oxygen as the original quinone. The 5OH-NQ metabolite collected during germination experiments showed differences in its absorption spectrum in comparison with 5OH-NQ, which suggest changes in structure. This metabolite was reduced by quinone reductase, but reduction of oxygen to superoxide radicals was not detected during its activation with homogenate from seeds. This metabolite may arise via a conjugation reaction, since the addition of 500 ?m uridine 5?-diphosphoglucuronic acid or 3?-phosphoadenosine-5?-phosphosulfate to the incubation mixture during activation of this metabolite by homogenate from seeds in vitro inhibited reduction of oxygen to superoxide radicals by 50 and 64%, respectively. The constitutive levels of superoxide dismutase and catalase were sufficient to prevent oxygen toxicity during activation of 5OH-NQ, since these enzymes were not induced when the seeds were treated with 200 ?m 5OH-NQ.
Segura-Aguilar, Juan; Hakman, Inger; Rydstrom, Jan
Arabidopsis thaliana DOF6 negatively affects germination in non-after-ripened seeds and interacts with TCP14
Seed dormancy prevents seeds from germinating under environmental conditions unfavourable for plant growth and development and constitutes an evolutionary advantage. Dry storage, also known as after-ripening, gradually decreases seed dormancy by mechanisms not well understood. An Arabidopsis thaliana DOF transcription factor gene (DOF6) affecting seed germination has been characterized. The transcript levels of this gene accumulate in dry seeds and decay gradually during after-ripening and also upon seed imbibition. While constitutive over-expression of DOF6 produced aberrant growth and sterility in the plant, its over-expression induced upon seed imbibition triggered delayed germination, abscisic acid (ABA)-hypersensitive phenotypes and increased expression of the ABA biosynthetic gene ABA1 and ABA-related stress genes. Wild-type germination and gene expression were gradually restored during seed after-ripening, despite of DOF6-induced over-expression. DOF6 was found to interact in a yeast two-hybrid system and in planta with TCP14, a previously described positive regulator of seed germination. The expression of ABA1 and ABA-related stress genes was also enhanced in tcp14 knock-out mutants. Taken together, these results indicate that DOF6 negatively affects seed germination and opposes TCP14 function in the regulation of a specific set of ABA-related genes.
Rueda-Romero, Paloma; Barrero-Sicilia, Cristina; Gomez-Cadenas, Aurelio; Carbonero, Pilar; Onate-Sanchez, Luis
Arabidopsis thaliana DOF6 negatively affects germination in non-after-ripened seeds and interacts with TCP14.
Seed dormancy prevents seeds from germinating under environmental conditions unfavourable for plant growth and development and constitutes an evolutionary advantage. Dry storage, also known as after-ripening, gradually decreases seed dormancy by mechanisms not well understood. An Arabidopsis thaliana DOF transcription factor gene (DOF6) affecting seed germination has been characterized. The transcript levels of this gene accumulate in dry seeds and decay gradually during after-ripening and also upon seed imbibition. While constitutive over-expression of DOF6 produced aberrant growth and sterility in the plant, its over-expression induced upon seed imbibition triggered delayed germination, abscisic acid (ABA)-hypersensitive phenotypes and increased expression of the ABA biosynthetic gene ABA1 and ABA-related stress genes. Wild-type germination and gene expression were gradually restored during seed after-ripening, despite of DOF6-induced over-expression. DOF6 was found to interact in a yeast two-hybrid system and in planta with TCP14, a previously described positive regulator of seed germination. The expression of ABA1 and ABA-related stress genes was also enhanced in tcp14 knock-out mutants. Taken together, these results indicate that DOF6 negatively affects seed germination and opposes TCP14 function in the regulation of a specific set of ABA-related genes. PMID:22155632
Rueda-Romero, Paloma; Barrero-Sicilia, Cristina; Gómez-Cadenas, Aurelio; Carbonero, Pilar; Ońate-Sánchez, Luis
Essential role of urease in germination of nitrogen-limited Arabidopsis thaliana seeds.
In Arabidopsis thaliana, urease transcript levels increased sharply between 2 and 4 d after germination (DAG) and were maintained at maximal levels until at least 8 DAG. Seed urease specific activity declined upon germination but began to increase in seedlings 2 DAG, reaching approximately 75% of seed activity by 8 DAG. Urea levels showed a small transient increase 1 DAG and then approximately paralleled urease activity, reaching maximal levels at approximately 9 DAG. Urease inhibition with phenylphosphorodiamidate resulted in a 2- to 4-fold increase in urea levels throughout seedling development. Arginine pools (0-8 DAG) changed approximately in parallel with the urea pool. Consistent with arginine being a major source of urea, arginase activity increased 10-fold in the interval 0 to 6 DAG. Allopurinol, a xanthine dehydrogenase inhibitor, had no effect on urea levels up to 3 DAG but reduced the urea pool by 30 to 40% during the interval 5 to 8 DAG, suggesting that purine degradation contributed to the urea pool well after germination, if at all. in aged Arabidopsis seeds, there was correlation between phenylphosphorodiamidate inactivation of urease and germination inhibition, the latter overcome by NH4NO3 or amino acids. Since urease activity, urea precursor, and urea increase in young seedlings, and since urease inactivation results in a nitrogen-reversible inhibition of germination, we propose that urease recycles urea-nitrogen in the seedling.
Zonia, L E; Stebbins, N E; Polacco, J C
Proteomic analysis of response to long-term continuous stress in roots of germinating soybean seeds.
Germination is a complex process, highly dependent on various environmental factors, including temperature and water availability. Germinating soybean seeds are especially vulnerable to unfavorable environmental conditions and exposure to long-term abiotic stresses may result in diminishing much of the yield and most importantly - restrained germination. In the present study, a proteomic approach was employed to analyze influence of cold and osmotic stress on roots of germinated soybean (Glycine max, L.) seeds. Seeds were germinating under continuous conditions of cold stress (+10°C/H2O), osmotic stress (+25°C/-0.2MPa) as well as cold and osmotic stress combined (+10°C/-0.2MPa). Proteome maps established for control samples and stress-treated samples displayed 1272 CBB-stained spots. A total of 59 proteins, present in both control and stress-treated samples and showing significant differences in volume, were identified with LC/nanoESI-MS. Identified proteins divided into functional categories, revealed 9 proteins involved in plant defense, 8 proteins responsible for plant destination and storage and 10 proteins involved in various tracks of carbohydrate metabolism. Furthermore, a number of proteins were assigned to electron transport, range of metabolic pathways, secondary metabolism, protein synthesis, embryogenesis and development, signal transduction, cellular transport, translocation and storage. By analyzing differences in expression patterns, it was possible to trace the soybean response to long-term abiotic stress as well as to distinguish similarities and differences between response to cold and osmotic stress. PMID:23394790
Swigonska, Sylwia; Weidner, Stanislaw
Ethylene Production is Associated with Germination but not Seed Dormancy in Red Rice
Background and Aims The relationship between ethylene production and both seed dormancy and germination was investigated using red rice (weedy rice) as a model species. Methods Both fully dormant and after-ripened (non-dormant) naked caryopses were incubated with or without inhibitors of ethylene synthesis [aminoethoxyvinylglycine (AVG)] and perception [silver thiosulfate (STS)], or in the presence of the natural ethylene precursor 1-aminocyclopropane-1-carboxylic acid (ACC). The kinetics of ethylene emissions were measured with a sensitive laser–photoacoustic system. Key Results Dormant red rice caryopses did not produce ethylene. In non-dormant caryopses, ethylene evolution never preceded the first visible stage of germination (pericarp splitting), and ethylene inhibitors completely blocked ethylene production, but not pericarp splitting. Accordingly, endogenous ACC appeared to be lacking before pericarp splitting. However, early seedling growth (radicle or coleoptile attaining the length of 1 mm) followed ethylene evolution and was delayed by the inhibitors. Wounding the dormant caryopses induced them to germinate and produce ethylene, but their germination was slow and pericarp splitting could be speeded up by ethylene. Conclusions The findings suggest that, in red rice, endogenous ethylene stimulates the growth of the nascent seedling, but does not affect seed dormancy or germination inception. Correspondingly, this phytohormone does not play a role in the dormancy breakage induced by wounding, but accelerates germination after such breakage has occurred.
Gianinetti, Alberto; Laarhoven, Lucas J. J.; Persijn, Stefan T.; Harren, Frans J. M.; Petruzzelli, Luciana
Effects of drying on sunflower seed oil quality and germination
Sunflower seed (SunGro 380) were harvested 101 to 121 days after planting, and their moisture levels were between 43 and 15%.\\u000a The seed were dried at 35, 53, 72, and 88 C to a final moisture level of 10% or below. Drying air flow was 2000 m3\\/hr.\\/m3 seed. Temperature had no effect on peroxide values, total oil, or fatty acid
W. Herbert Morrison; J. A. Robertson
Stimulation of Orobanche ramosa seed germination by fusicoccin derivatives: a structure-activity relationship study.
A structure-activity relationship study was conducted assaying 25 natural analogues and derivatives of fusicoccin (FC), and cotylenol, the aglycone of cotylenins, for their ability to stimulate the seed germination of the parasitic species Orobanche ramosa. Some of the compounds tested proved to be highly active, being 8,9-isopropylidene of the corresponding FC aglycone and the dideacetyl derivative the most active FC derivatives. In both groups of glucosides and aglycones (including cotylenol), the most important structural feature to impart activity appears to be the presence of the primary hydroxy group at C-19. Furthermore, the functionalities and the conformation of the carbotricyclic ring proved to play a significant role. The dideacetyl derivative of FC, being easily and rapidly obtainable in high yield starting by FC, could be of interest for its practical application as a stimulant of Orobanche ramosa seed germination, inducing the "suicidal germination", an interesting approach for parasitic plant management. PMID:16310229
Evidente, Antonio; Andolfi, Anna; Fiore, Michele; Boari, Angela; Vurro, Maurizio
Trigoxazonane, a monosubstituted trioxazonane from Trigonella foenum-graecum root exudate, inhibits Orobanche crenata seed germination.
Orobanche crenata is a major threat to grain legume production. Fenugreek (Trigonella foenum-graecum) is an annual legume that has been shown to effectively reduce O. crenata infection when intercropped with grain legumes. In this paper, we point that this can be attributed to allelopathy, through inhibition of the germination of O. crenata by fenugreek root exudates. The main inhibitory metabolite was isolated and characterized. Allelopathy was demonstrated in different bioassays, by inhibition of O. crenata seeds germination both by growing fenugreek and pea plants together (intercropped), and by application of fenugreek root exudates. Fenugreek root exudates were extracted with organic solvent and fractionated giving several fractions, two of which showed moderate (27%) and strong (54%) inhibition of O. crenata seed germination, respectively. The most active metabolite is a new monosubstituted trioxazonane, characterized by spectroscopic methods as the 2-butyl-[1,4,7,2]trioxazonane and named trigoxazonane. PMID:17604061
Evidente, Antonio; Fernández-Aparicio, Mónica; Andolfi, Anna; Rubiales, Diego; Motta, Andrea
Mimosine and albizziine are two toxic, non-protein amino acids found in several legume species. Both compounds have been shown to inhibit seed germination and seedling growth, but no comparative study of the two compounds has been conducted. In the present study the 10-3 M concentration of both com...
Field emergence and plant density of sand bluestem lines selected for increased seed germination.
Sand bluestem (Andropogon hallii Hack.) populations AB-medium Syn-1 and Syn-2, and CD-tall Syn-1 and Syn-2 were developed from populations AB-medium Syn-0 and CD-tall Syn-0 by recurrent selection for increased seed germination in low water potentials. The objective of this research was to verify if...
Post-pollen-germination barriers to seed set in sweet-potato
Three sweet-potato crossing combinations selected for good pollen germination were characterized by a moderate to high amount of failure of tubes to pass from stigma to style. The number of tubes penetrating the style was about 6 times the number of seeds produced. Ovules of compatibly pollinated flowers were divided into two classes, by size. Larger (probably fertilized) ovules matured
F. W. Martin; E. Cabanillas
Effects of plant hormones and 20-hydroxyecdysone on tomato (Lycopersicum esculentum) seed germination and seedlings growth
20-hydroxyecdysone (20E) is the major phytoecdysteroid of about 6% of plants. Its role in plant physiology has not been fully elucidated. In this work we studied the effects of 20E application on some morphological and biochemical parameters of tomato, Lycopersicum esculentum, seed during germination and seedling development (5 d). We compared the 20E effects with the action of phytohormones: gibberellic
Ahmed Bakrim; Mostapha Lamhamdi; Fouad Sayah; Fatiha Chibi
Effects of fungicides and bactericides on orchid seed germination and shoot tip cultures in vitro
Amphotericin B, benomyl, gentamycin, nystatin, quintozene penicillin G, sodium omadine, and vancomycin singly and in several\\u000a combinations have no deleterious effects on the germination of orchid seeds, but inhibit the growth in vitro of shoot tip\\u000a explants.
D. M. Brown; C. L. Groom; M. Cvitanik; M. Brown; J. L. Cooper; J. Arditti
Seed Germination Response of Rapid?Cycling Brassica oleracea Grown Under Increasing Sodium Selenate
Breeding plants to be more efficient at micronutrient accumulation is a proposed strategy for fighting worldwide malnutrition of humans. Selection for increased selenium (Se) in Brassica oleracea L. is possible. However, when present at high levels, micronutrients such as Se can affect seed germination and subsequently hamper breeding efforts. The objectives of this study were: (1) to evaluate the accumulation
Dean A. Kopsell; David E. Kopsell; William M. Randle
The coastal and near coastal habitats of Karachi, Pakistan are characterized by dominant stands of perennial halophytes like Aeluropus lagopoides, Desmostachya bipinnata, Haloxylon stocksii and Suaeda fruticosa. Experiments were carried out to investigate comparative effects of NaCl and seasalt salinity on both rate and final seed germination of these species. Salinity tolerance range of halophytes varied among species and also
Seed germination and seedling survival of two threatened endemic species of the northwest Iberian peninsula
We examined germination and seedling survival of Petrocoptis grandiflora and Petrocoptis viscosa (Caryophyllaceae), two narrow endemic species from the northwest Iberian Peninsula. The experiments were carried out with seeds of three of eight populations of P. grandiflora and one of the three sole populations of P. viscosa. Under natural conditions, both P. grandiflora and P. viscosa produce very large numbers
Luis Navarro; Javier Guitián
The Early Soybean Production System (ESPS) has been applied to the Southern Central area in the U.S. to maintain soybean (Glycine max Merrill) yield by avoiding drought. However, ESPS can produce seeds with good compositional quality but low germination and vigor. Our hypothesis is that high tempera...
Ecotoxicological Effects of Tonalide on Seed Germination and Seedling Development of Wheat (Triticum aestivum L.)
In order to obtain a comprehensive understanding about the toxicity of AHTN, the influences of AHTN on seed germination and the antioxidant enzymes in the growth of early seedlings of wheat (Triticum aestivum L.) were investigated. The results showed that AHTN had inhibition effects on the shoot elongation of wheat seedlings. And lower concentrations of AHTN (50-100 mg\\/kg) would promote
Su Chen; Lina Sun; Lei Chao; Tieheng Sun; Jing An
Ecotoxicological effects of paracetamol on seed germination and seedling development of wheat ( Triticum aestivum L.)
In order to assess ecological risk of pharmaceutical compounds entering into agricultural ecosystems, toxic effects of paracetamol with therapeutic action on wheat (Triticum aestivum L.) were investigated as an example, using early growing and developmental indexes of wheat, including seed germination, shoot height and root length, peroxidase, superoxide dismutase, chlorophyll, and soluble protein in the seedlings. The results showed that
Jing An; Qixing Zhou; Fuhong Sun; Lei Zhang
Phenolic acids as potential seed germination-inhibitors in animal-waste composts
A laboratory experiment was conducted to investigate the presence of phenolic acids in some animal-waste composts as well as their biological activity on the germination of sorghum (Sorghum bicolor Moench) seeds. Nine samples of composts, three in each group of cattle-, chicken-, and hog-waste composts, were extracted with deionized water at the rates of 10, 40, and 80 g L.
Buddhi Marambe; Tadao Ando
Allelopathic effects of sorghum extracts on Amaranthus retroflexus seed germination and growth
With regards to importance and abundance of Amaranthus retroflexus weed in fields an experiment was conducted using CRD based factorial design with three replications to study the allelopathic effects of sorghum extracts on germination and growth of Amaranthus retroflexus in 2008-2009. Treatments were: harvesting stage of extracted sorghum (vegetative, flowering and seed filling stage), extracted plant part (leaf, stem, root
M. Yarnia; M. B. Khorshidi Benam; E. Farajzadeh Memari Tabrizi
Ontogeny of glyoxysomes in maturing and germinated cotton seeds—a morphometric analysis
Morphometric procedures were used with light and electron microscopy to examine glyoxysome number, volume, shape and distribution as well as mesophyll cell volume, in cotyledons of mature (50 d postanthesis), imbibed (5h) and germinated (24 and 37 h) cotton (Gossypium hirsutum L.) seeds. Additionally, activities of five glyoxysomal marker enzymes in cotyledon extracts were assayed at each of the above
Christine M. Kunce; Richard N. Trelease; Diane C. Doman
Starch grain breakdown in cotyledon cells of germinating mung bean seeds
Ultrastructural aspects of the breakdown of starch grains during the mobilisation of reserves in Phaseolus aureus Roxb. seed germination are described. The starch grains show erosion from within leading to the formation of a hollow shell. The erosion is accompanied by intrusion of cytoplasm into the shell. No evidence of a vesicular transport system to or from the eroding face
N. Harris
Effects of podocarp extracts on lettuce seed germination and seedling growth
The effects of ethanol extracts from 16 of the 17 New Zealand species in the family Podo-carpaceae on the germination of lettuce seeds and hypocotyl elongation are reported. Extracts of both juvenile and adult forms of Halocarpus kirkii and Halocarpus bidwillii were tested. Each extract was tested at three different levels: undiluted, and diluted × 10 and × 10. The
N. B. Perry; L. M. Foster; P. E. Jameson
MicroRNAs are key regulatory molecules that play critical roles in developmental processes in plants and animals. To gain a better understanding of the regulation of gene expression in seed germination, an efficient screening system was developed to examine microRNAs present during various stages o...
In Vivo Effects of Barbituates on Seed Germination and Seedling Growth.
|A simple, low-cost experimental system can be used to demonstrate the "in vivo" effects of barbituates on seed germination and seedling growth behavior in different plant species. Lipid solubility and concentration of individual barbituates both affect the response. List of materials needed, procedures used, and typical results obtained are…
Kordan, H. A.
Phytohormone signalling pathways interact with sugars during seed germination and seedling development
Exogenous glucose delays seed germination in Arabi- dopsis thaliana not only in wild type (WT), but also in a number of mutants in hormone signalling pathways. This study demonstrates that the ABA Insensitive 3 (ABI3) gene in the ABA signalling pathway and the RGA-like 2 (RGL2) and SPINDLY (SPY) genes in the GA signalling pathways all play important roles in
Kun Yuan; Joanna Wysocka-Diller
Temperature effect on seed germination, seedling root development and growth of several vegetables
Experiments were conducted to study the effect of temperature and nutrition on seed germination and plant growth of different plant species. The nutrition studies of vegetables showed a normal response to fertilization rates on deficient soils at temperatures above their critical minimum. At soil temperatures below this little or no response was obtained to increased P concentration. Plant growth as
Gerald E. Wilcox; Charles L. Pfeiffer
Mycorrhizal fungi of Vanilla: diversity, specificity and effects on seed germination and plant growth
Mycorrhizal fungi are essential for the germination of orchid seeds. However, the specificity of orchids for their mycorrhizal fungi and the effects of the fungi on orchid growth are controversial. Mycorrhizal fungi have been studied in some tem- perate and tropical, epiphytic orchids, but the symbionts of tropical, terrestrial orchids are still unknown. Here we study diversity, specificity and function
Andrea Porras-Alfaro; Paul Bayman
Identification of QTLs for seed germination capability after various storage periods using two RIL populations in rice
Seed germination capability of rice is one of the important traits in the production and storage of seeds. Quantitative trait\\u000a loci (QTL) associated with seed germination capability in various storage periods was identified using two sets of recombinant\\u000a inbred lines (RILs) which derived from crosses between Milyang 23 and Tong 88-7 (MT-RILs) and between Dasanbyeo and TR22183\\u000a (DT-RILs). A total
Wenzhu Jiang; Joohyun Lee; Yong-Mei Jin; Yongli Qiao; Rihua Piao; Sun Mi Jang; Mi-Ok Woo; Soon-Wook Kwon; Xianhu Liu; Hong-Yu Pan; Xinglin Du; Hee-Jong Koh
Chlorophyll in desiccated seeds of a euhalophyte, Suaeda physophora, and its significancy in plant adaptation to salinity during germination.
The seed cotyledons of a euhalophyte, Suaeda physophora, were found to be dark green. The pigment extracted from the cotyledons was proved to be chlorophyll for the absorption spectra curve of extracts the same as that for leaves. Photosynthetic oxygen-exchanging could be detected after the seeds were moistened for 6 h. Microstructure of organelles in cotyledons of ungerminated seeds was detected by transmission electron microscopy. Histochemical pigmentation was used to investigate the degree of damage on the membrane of radicles. A xerophyte, Haloxylon persicum, whose cotyledons of desiccated seeds also contain chlorophyll was used as a comparative species. The results showed that S. physophora maintained the ultra-structure of chloroplasts, the integrity of plasma membranes of radicles kept much better than that of H. persicum, which showed the great adaptability to salinity of the euhalophyte even at the seed-germination stage. Seeds were incubated in 0 and 700 mmol/L NaCl for 10 days in darkness at 20 degrees C, then ungerminated seeds in NaCl solution were transferred to deionised water and reincubated for another 8 days and was recorded the germination recovery. Dry seeds moistened with deionised water germinated gradually in the dark and germination was maximal after 3 or 4 d. Seeds at 700 mmol/L NaCl for 10 d and transferred back to deionised water germinated abruptly, most seeds germinated in one day and photosynthesis was also detected. It is concluded that recovery germination of S. physophora ensured the seeds could germinate rapidly after salinity declines, for example under the mild but transitory favorable edaphic condition in early spring. Photosynthesis function in seeds might also promoted radicle growth and seedling establishment. PMID:18785586
Li, Yang; Zhang, ShiRong; Song, Jie; Wu, ChenXi; Tian, ChangYan; Feng, Gu
Sterol and triterpene synthesis in the developing and germinating pea seed
Developing and germinating pea seeds were compared with respect to their capacity to incorporate mevalonate into sterols and triterpenes. The capacity for sterol synthesis is greatest in the least mature fruits and decreases during their development. Label is shown, by gas–liquid chromatography and counting the radioactivity of trapped fractions, to be associated with campesterol, ?-sitosterol and isofucosterol. During early stages of germination sterol synthesis is insignificant. The triterpene fraction becomes heavily labelled during both development and germination. The label is associated almost exclusively with ?-amyrin during germination but with cycloartenol and 24-methylenecycloartanol during development. It is only in the terminal stages of maturation that ?-amyrin becomes significantly labelled. At the same time an unidentified radioactive polar compound appears. The possible significance of the appearance of this polar compound and the regulation of the synthesis of these higher terpenoids is discussed.
Baisted, D. J.
Seed Maturity, Germination, and Endophyte Relationships in Tall Fescue
siderable negative attention from a seed quality point of view. Thus, efforts were made to remove endophytes Endophytic fungi were once considered detrimental components from the host species to alleviate toxicosis syndromes of cool season pasture grass seed because of their association with toxic compounds. Development of new cultivars of forage grasses of grazing livestock. infected with nontoxic endophytes suggests
N. S. Hill; J. H. Bouton; E. E. Hiatt; B. Kittle
Seed Germination Patterns in Green Dragon (Arisaema dracontium, Araceae)
Arisaema dracontium (green dragon) is a perennial herb that is widely distributed in eastern North America. However, in Canada, at the northern edge of its distribution, the species is designated as ''vulnerable'' with respect to conservation status. In natural populations, seedlings are uncommon; the present study was undertaken in order to characterize seed and seedling properties in green dragon. Seeds
J. Yang; J. Lovett-Doust; L. Lovett-Doust
Influence of environmental factors on Vallisneria americana seed germination
Over the course of a growing season (April–October) water quality (water temperature, light, salinity, dissolved oxygen) and reproductive phenology (biomass, production of flowering shoots and seed pods, seed bank densities) were quantified in three Vallisneria americana beds in Nanjemoy Creek, MD, a tributary to the Chesapeake Bay. Clonal production of V. americana biomass increased at all sites when water temperatures
Jessie C. Jarvis; Kenneth A. Moore
An allelopathic substance exuded from germinating watermelon seeds
When watermelon seeds were cultured in a Petri dish together with amaranth, barnyard grass, cockscomb, lettuce or tomato seeds, the shoot growth of amaranth and cockscomb was markedly promoted, whereas the shoot growth of lettuce and tomato was inhibited. The shoot growth of barnyard grass was not affected. These results suggest that plant-selective allelopathic substance(s) affecting the shoot growth of
Midori Kushima; Hideo Kakuta; Seiji Kosemura; Shosuke Yamamura; Kosumi Yamada; Kaori Yokotani-Tomita; Koji Hasegawa
Dung beetles as secondary seed dispersers: impact on seed predation and germination
Dispersal of seeds away from the parent plant may facilitate escape from density-dependent seed mortality. However, many post-dispersal events can have a profound influence on the survival of dispersed seeds. By incorporating seeds in the dung that dung beetles process for consumption and oviposition, dung beetles could enhance seed survival if they remove seeds from areas of high pre- dation
ABA treatment of germinating maize seeds induces VP1 gene expression and selective promoter-associated histone acetylation.
Seed germination commences from a low metabolic state to a bioactive state and is associated with changes in the pattern of gene expression. Recent studies have revealed that epigenetic processes are involved in abscisic acid (ABA)-regulated seed germination processes. In this study, we showed that the expression of both histone acetyltransferases (HATs) and histone deacetylases (HDACs) was increased gradually during seed germination accompanying an increase in overall acetylation level of histone H3. Application of exogenous ABA repressed the expression of HATs as well as HDACs and delayed histone acetylation. Suppressing HDAC by treatment with an HDAC inhibitor, trichostatin A (TSA), led to an increase in global histone acetylation and inhibited seed germination and growth. However, ABA and TSA both delayed the downregulation of the embryogenesis-related gene viviparous1 (VP1) during seed germination. The further chromatin immunoprecipitation experiments showed that the promoter region of the VP1 gene was deacetylated during seed germination, and this deacetylation event was inhibited by both ABA and TSA. These results suggested that a balance of the two enzymes HATs and HDACs affected the acetylation status of the VP1 gene and ABA selectively activated its transcription by an accumulation of acetylated histone H3 associated with the promoter region during seed germination. PMID:21679193
Zhang, Lu; Qiu, Zhengming; Hu, Yong; Yang, Fei; Yan, Shihan; Zhao, Lin; Li, Bo; He, Shibin; Huang, Min; Li, Jun; Li, Lijia
Lead-induced phytotoxicity mechanism involved in seed germination and seedling growth of wheat (Triticum aestivum L.).
The mechanism of lead-inhibitory effects on seed germination and seedling growth was investigated in wheat cv. Xihan 2 subjected to different Pb(NO(3))(2) concentrations. High concentrations of lead and exogenous H(2)O(2) significantly inhibited seed germination and the growth of roots and shoots. Dimethylthiourea, catalase or diphenylene iodonium could reverse lead-inhibitory effects on seed germination. Significant elevated H(2)O(2) generation was observed in germinating seeds exposed to lead. Analysis using fluorescent dye 2',7'-dichlorodihydrofluorescein diacetate showed significantly increased H(2)O(2) level in the root tissue in response to lead treatment. Nitric oxide (NO) donor sodium nitroprusside could alleviate the Pb-inhibitory effects on seed germination and shoot growth, which was blocked by guanylyl cyclase inhibitor methylene blue. Therefore, NADH-dependent generation of extracellular H(2)O(2) is responsible for Pb-inhibitory effect on seed germination, the protection of exogenous NO against lead toxicity involved in seed germination and seedlings shoot growth may be associated with cGMP signaling pathway. PMID:20833428
Yang, Yingli; Wei, Xueling; Lu, Jin; You, Jia; Wang, Wenrui; Shi, Ruxia
Effects of cryopreservation of Phaseolus vulgaris L. seeds on early stages of germination.
In this work, we studied the effects of cryopreservation on various parameters of early stages of germination of Phaseolus vulgaris seeds (0, 7 and 14 days). Percentages of germination, fresh mass of different plant parts, levels of chlorophyll pigments (a, b, total), malondialdehyde, other aldehydes, phenolics (cell wall-linked, free, and total) and protein were determined. No phenotypic changes were observed visually in seedlings recovered from cryopreserved seeds. However, several significant effects of seed liquid nitrogen exposure were recorded at the biochemical level. There was a significant negative effect of cryopreservation on shoot protein content, which decreased from 3.11 mg g(-1) fresh weight for non-cryopreserved controls to 0.44 mg g(-1) fresh shoot weight for cryopreserved seeds. On the other hand, cryopreservation significantly increased levels of other aldehydes than malondialdehyde in shoots at day 7, from 56.47 ?mol g(-1) for non-cryopreserved controls to 253.19 ?mol g(-1) fresh shoot weight for cryopreserved samples. Liquid nitrogen exposure significantly reduced phenolics contents (free, cell-wall linked, total) in roots at day 7 after onset of germination. In general, roots were more affected by cryostorage compared with other plant parts, while leaves were the least affected. The effects of seed cryopreservation seem to decline progressively along with seedling growth. PMID:22843025
Cejas, Inaudis; Vives, Karel; Laudat, Taletha; González-Olmedo, Justo; Engelmann, Florent; Martínez-Montero, Marcos Edel; Lorenzo, José Carlos
Seed germination in response to diurnal fluctuations of temperature
DIURNAL fluctuations in temperature may initiate or accelerate germination in certain flowering plants1-6, and the effectiveness of the stimulus varies according to the amplitude of fluctuation7 and the presence or absence of light8. Attempts3,6 to assess the adaptive significance of the phenomenon, however, have been limited by the scarcity of data for species of contrasted ecology. We report here an
K. Thompson; J. P. Grime; G. Mason
Effect of herbicide Imazethapyr (pursuit™) on chickpea seed germination
Herbicides are the most successful weed control technology ever developed. To assess the effects of herbicides on non-target plants, a study was carried out by using Imazethapyr (IM) on JG-11 cultivar of chickpea germination and early growth. Hydroponic conditions with five concentrations (0.5, 1, 2.5, 5, and 10 ppm) of IM were employed along with control. On the termination day
Manijeh Hoseiny-Rad; Shobha Jagannath
Laboratory Studies of Thermotolerance Acquisition during Seed Imbibition and Germination.
|Describes a series of low-cost experiments to investigate the ability of seeds from different species to acquire tolerance of thermal stress. Suggests links to discussions on molecular biology, physiology, ecology, and evolution. (WRM)|
Choinski, John S., Jr.
Antagonism between abscisic acid and gibberellins is partially mediated by ascorbic acid during seed germination in rice.
The antagonism between abscisic acid (ABA) and gibberellin (GA) plays a key role in controlling seed germination, but the mechanism of antagonism during this process is not known. In the associated study, we investigated the relationship among ABA, reactive oxygen species (ROS), ascorbic acid (ASC) and GA during rice seed germination. ROS production is reduced by ABA, which hence results in decreasing ASC accumulation during imbibition. GA accumulation was also suppressed by a reduced ROS and ASC level, whereas application of exogenous ASC can partially rescue seed germination from ABA treatment. Further results show that production of ASC, which acts as a substrate in GA biosynthesis, was significantly inhibited by lycorine which thus suppressed the accumulation of GA. Consequently, expression of GA biosynthesis genes was suppressed by the low levels of ROS and ASC in ABA-treated seeds. These studies reveal a new role for ASC in mediating the antagonism between ABA and GA during seed germination in rice. PMID:22516812
Ye, Nenghui; Zhang, Jianhua
The role of the Arabidopsis FUSCA3 transcription factor during inhibition of seed germination at high temperature
Background Imbibed seeds integrate environmental and endogenous signals to break dormancy and initiate growth under optimal conditions. Seed maturation plays an important role in determining the survival of germinating seeds, for example one of the roles of dormancy is to stagger germination to prevent mass growth under suboptimal conditions. The B3-domain transcription factor FUSCA3 (FUS3) is a master regulator of seed development and an important node in hormonal interaction networks in Arabidopsis thaliana. Its function has been mainly characterized during embryonic development, where FUS3 is highly expressed to promote seed maturation and dormancy by regulating ABA/GA levels. Results In this study, we present evidence for a role of FUS3 in delaying seed germination at supraoptimal temperatures that would be lethal for the developing seedlings. During seed imbibition at supraoptimal temperature, the FUS3 promoter is reactivated and induces de novo synthesis of FUS3 mRNA, followed by FUS3 protein accumulation. Genetic analysis shows that FUS3 contributes to the delay of seed germination at high temperature. Unlike WT, seeds overexpressing FUS3 (ML1:FUS3-GFP) during imbibition are hypersensitive to high temperature and do not germinate, however, they can fully germinate after recovery at control temperature reaching 90% seedling survival. ML1:FUS3-GFP hypersensitivity to high temperature can be partly recovered in the presence of fluridone, an inhibitor of ABA biosynthesis, suggesting this hypersensitivity is due in part to higher ABA level in this mutant. Transcriptomic analysis shows that WT seeds imbibed at supraoptimal temperature activate seed-specific genes and ABA biosynthetic and signaling genes, while inhibiting genes that promote germination and growth, such as GA biosynthetic and signaling genes. Conclusion In this study, we have uncovered a novel function for the master regulator of seed maturation, FUS3, in delaying germination at supraoptimal temperature. Physiologically, this is important since delaying germination has a protective role at high temperature. Transcriptomic analysis of seeds imbibed at supraoptimal temperature reveal that a complex program is in place, which involves not only the regulation of heat and dehydration response genes to adjust cellular functions, but also the activation of seed-specific programs and the inhibition of germination-promoting programs to delay germination.
Spatially and genetically distinct control of seed germination by phytochromes A and B
Phytochromes phyB and phyA mediate a remarkable developmental switch whereby, early upon seed imbibition, canopy light prevents phyB-dependent germination, whereas later on, it stimulates phyA-dependent germination. Using a seed coat bedding assay where the growth of dissected embryos is monitored under the influence of dissected endosperm, allowing combinatorial use of mutant embryos and endosperm, we show that canopy light specifically inactivates phyB activity in the endosperm to override phyA-dependent signaling in the embryo. This interference involves abscisic acid (ABA) release from the endosperm and distinct spatial activities of phytochrome signaling components. Under the canopy, endospermic ABA opposes phyA signaling through the transcription factor (TF) ABI5, which shares with the TF PIF1 several target genes that negatively regulate germination in the embryo. ABI5 enhances the expression of phytochrome signaling genes PIF1, SOMNUS, GAI, and RGA, but also of ABA and gibberellic acid (GA) metabolic genes. Over time, weaker ABA-dependent responses eventually enable phyA-dependent germination, a distinct type of germination driven solely by embryonic growth.
Lee, Keun Pyo; Piskurewicz, Urszula; Tureckova, Veronika; Carat, Solenne; Chappuis, Richard; Strnad, Miroslav; Fankhauser, Christian; Lopez-Molina, Luis
Role of Ethylene in Lactuca sativa cv `Grand Rapids' Seed Germination
Promotion of thermoinhibited (30°C) lettuce (Lactuca sativa cv `Grand Rapids') seed germination by ethylene is similar to the action of the gas in other hormonal systems. Ethylene was more active than propylene and ethane was inactive. An inhibitor of ethylene production, aminoethoxy-vinylglycine, reduced ethylene evolution and germination. Inhibitors of ethylene action such as, 5-methyl-7-chloro-4-ethoxycarbonylmethoxy-2,1,3-benzothiadiazole, 2,5-norbornadiene, and silver thiosulfate inhibited germination and the effect was reversed by the addition of ethylene to the gas phase. The action of ethylene appears to be due to the promotion of radial cell expansion in the embryonic hypocotyl. The action of N6-benzyladenine and fusiccocin, which also overcome thermoinhibition, appears to be due to a promotion of hypocotyl elongation. None of the germination promoters studied appeared to function by lowering the mechanical resistance of the endosperm to embryonic growth. Data presented here are consistent with the view that ethylene plays a role in lettuce seed germination under thermoinhibited and normal conditions.
Abeles, Fred B.
The mobilization of defence mechanisms in the early stages of pea seed germination against Ascochyta pisi.
Ascochyta pisi is a necrotrophic pathogenic fungus, which mainly survives between seasons through infected seeds. Defence responses of pea embryo axes to A. pisi were investigated in the heterotrophic phase of seed germination and during the transition from the heterotrophic to the autotrophic phase. Germinated pea seeds, both non-inoculated and inoculated with A. pisi, were cultured in perlite for 96 h. Polarographic studies performed on intact embryo axes of germinating pea seeds infected with A. pisi showed a high respiratory intensity in time from 48 to 96 h after inoculation. Forty-eight-hour embryo axes of germinating pea seeds exhibited the highest respiration rate, which in infected axes was maintained at the following time points after inoculation. Moreover, at 72 and 96 h after inoculation, respiratory intensity was by 64% and 73% higher than in the control. Electron paramagnetic resonance analysis revealed a higher concentration of semiquinone free radicals with g values of g (||) = 2.0031 ± 0.0004 and g (?) = 2.0048 ± 0.0004 in infected axes than in the control. Generation of superoxide anion radical was also higher in infected axes than in the control but stronger at 72 and 96 h after inoculation. Starting from 72 h after infection, the level of Mn(2+) ions in infected axes decreased in relation to the control. At the same time, the highest activity of superoxide dismutase (EC 220.127.116.11) and catalase (EC 184.108.40.206) was observed in 72-h infected axes. In turn, the activity of peroxidase (EC 126.96.36.199) up to 72 h after infection was lower than in the control. In 48-h infected embryo axes, a very high level of pterocarpan pisatin was observed. Infection of germinating pea seeds with A. pisi restricted mainly the growth of the epicotyl, but did not inhibit the increase in length and fresh weight of root embryo axes versus cultivation time. These results indicate that in pea during the stages of seed germination and early seedling growth, protective mechanisms are induced in embryo axes against A. pisi. PMID:22274650
Morkunas, Iwona; Formela, Magda; Marczak, Lukasz; Stobiecki, Maciej; Bednarski, Waldemar
Reduced germination of Orobanche cumana seeds in the presence of Arbuscular Mycorrhizal fungi or their exudates.
Broomrapes (Orobanche and Phelipanche spp) are parasitic plants responsible for important crop losses, and efficient procedures to control these pests are scarce. Biological control is one of the possible strategies to tackle these pests. Arbuscular Mycorrhizal (AM) fungi are widespread soil microorganisms that live symbiotically with the roots of most plant species, and they have already been tested on sorghum for their ability to reduce infestation by witchweeds, another kind of parasitic plants. In this work AM fungi were evaluated as potential biocontrol agents against Orobanche cumana, a broomrape species that specifically attacks sunflower. When inoculated simultaneously with O. cumana seeds, AM fungi could offer a moderate level of protection against the broomrape. Interestingly, this protection did not only rely on a reduced production of parasitic seed germination stimulants, as was proposed in previous studies. Rather, mycorrhizal root exudates had a negative impact on the germination of O. cumana induced by germination stimulants. A similar effect could be obtained with AM spore exudates, establishing the fungal origin of at least part of the active compounds. Together, our results demonstrate that AM fungi themselves can lead to a reduced rate of parasitic seed germination, in addition to possible effects mediated by the mycorrhizal plant. Combined with the other benefits of AM symbiosis, these effects make AM fungi an attractive option for biological control of O. cumana. PMID:23145139
Louarn, Johann; Carbonne, Francis; Delavault, Philippe; Bécard, Guillaume; Rochange, Soizic
[Effects of root exudates of squash grafted with cucumber shoot on seed germination].
Cucumber (Cucumis statirus L.) is commonly cultivated by grafting on squash (Cucurbita moschata) in commercial production. The effects of root exudates of squash grafted with cucumber on seed germination rate of cucumber and squash were tested. In this study, the exudates of cucumber-grafted squash roots were continuously collected with XAD-4 resin, and were further diluted with distilled water to make 5%, 10%, 20% and 40% concentrations. Cucumber and squash seeds were used for bioassay. The seeds were germinated in glass petri dishes with 2 filter papers at bottoms and containing 5 mL the diluted root exudates. The results showed that the exudates of cucumber-grafted squash roots significantly inhibit germination rate, radicel and hypocotyl elongation in cucumber and squash, and the inhibitory rate positively correlate with the concentration of the grafted cucumber root exudates. So grafted cucumber still have allelopathy. The exudates of cucumber-grafted squash roots significantly stimulated IAA oxidase activity in cucumber and squash. As a result, they decrease IAA level in cucumber and squash, and restrained their growth. The exudates of cucumber-grafted squash roots also decrease significantly the activities of amylase and alpha-amylase in cucumber and squash, and this decrease effects were strengthening with the increasing of the concentration of the grafted cucumber root exudates. So the exudates of cucumber-grafted squash roots can inhibit the hydrolysis and utilization of starch in cucumber and squash, and thereby suppress germination and seedling growth. PMID:15840942
Qi, Jian-Hua; Liang, Yin-Li; Liang, Zong-Suo
Influences of interyear rainfall variability and microhabitat on the germinable seed bank of annual plants in a sandy Monte Desert
We addressed the effects of growing-season rainfall of two consecutive years and of two microhabitats on seed density and floristic composition of the germinable seed bank of annual plants in a sandy desert. We hypothesised that seed composition and density is affected by the presence of vegetated patches, but that this effect varies according to rainfall. We predict an overall
L. Quevedo-Robledo; E. Pucheta; Y. Ribas-Fernández
Germination responses of the invasive Calotropis procera (Ait.) R. Br. (Apocynaceae): comparisons with seeds from two ecosystems in northeastern Brazil.
Life history traits are considered key indicators of plant invasibility. Among them, the germination behavior of seeds is of major relevance because it is influenced by environmental factors of invaded ecosystem. Here, we investigated how seed traits and seed tolerance to environmental factors on seed germination of Calotropis procera vary depending on the invaded ecosystems in northeastern Brazil. We have tested seeds from two vegetation types - Caatinga and Restinga - to different levels of light intensity, salinity, and water stress. Previous to those experiments, seed-set and morphometric analysis were carried out for both studied populations. We have observed a higher seed-set in Caatinga. Seeds produced in this ecosystem had lower seed moisture content. Seeds from Restinga showed lower germination time when light intensity decreased. We observed a reduction in both the germinability and the synchronization index with decreasing osmotic potential and increasing salinity. Nevertheless, both populations exhibited changes in photoblastism when seeds were submitted to water and saline stress. In conclusion, C. procera seeds are tolerant to environmental factors assessed. That characteristic ensures the colonization success and wide distribution of this plant species in the studied ecosystems. PMID:24068090
Leal, Laura C; Meiado, Marcos V; Lopes, Ariadna V; Leal, Inara R
Is reduced seed germination due to water limitation a special survival strategy used by xerophytes in arid dunes?
Using multi-sampling methods, seeds of xerophytic species, Caragana korshinskii, Artemisia sphaerocephala, and Hedysarum scoparium were collected from semi-arid regions of northwest China, while those of Reaumuria soongorica and Zygophyllum xanthoxylum were harvested from arid regions. Seed germination in these five species was studied under water limiting conditions, imposed by increasing concentrations of polyethylene glycol (PEG 6000). Seeds of C. korshinskii,
Yan Jun Zeng; Yan Rong Wang; Ju Ming Zhang
7 CFR 201.29a - Germination of vegetable seed in containers of more than 1 pound.
...vegetable seed in containers of more than 1 pound. 201.29a Section 201.29a Agriculture Regulations of the Department of Agriculture...ACT REGULATIONS Labeling Vegetable Seeds § 201.29a Germination of vegetable seed in containers of...
Sensitivity of two wheat species's seeds (Triticum durum, variety Karim and Triticum aestivum, variety Salambô) to heat constraint during germination.
The aim of this study is determine the effect of different temperature regimes on germination of wheat seeds and early germination events. Germination is very sensitive to environment conditions, particularly the temperature. Physiological and biochemical responses of wheat seed germination during time at various temperatures (5, 15, 25, 35 and 45 degrees C) have shown that optimal temperature (25 degrees C) favorites a good aptitude to germinate, whereas low (5 degrees C) and high temperature (45 degrees C) were extend the delay of germination. Residuary dry matter's mass of germinating, both Karim and Salambô wheat species, Seeds at 5 and 45 degrees C decreased lightly. This show a less mobilization of reserves to embryo. The activity of totals solubles peroxidases changes with temperature of wheat seed germination. At low (5 degrees C) and high (45 degrees C) temperatures, for both two cultivars, peroxidase activity decreases during germination. With exception, during imbibition (2 h), only 45 degrees C involves a high stimulation of this activity for Karim cultivar. This increase is considered as a biochemical response to high temperature. In control temperature (25 degrees C), we have obtained a light increase in peroxidase activity in comparison with that of dry seeds for both these two wheat species. At the end of this study, we have studied the effect of heat stress on totals proteins content. Nevertheless, both for these two wheat cultivars, at 5 degrees C there is no a markedly change in proteins amount during germination. In control condition (25 degrees C) of germination, there is a slight decrease in this content. Germination under high temperature, for Karim variety, induces a rapid synthesis of Heat Shock Proteins (HSPs) and concomitantly a weak degradation of normal proteins. The opposite phenomenon was observed for Salambô variety (weak synthesis of HSPs and important degradation of normal proteins). PMID:19090228
Essemine, Jemâa; Ammar, Saďda; Jbir, Najoua; Bouzid, Sadok
Antioxidant activity associated with lipid and phenolic mobilization during seed germination of Pangium edule Reinw.
Seeds of the tropical tree Pangium edule Reinw. are widely eaten in Southeast Asia after some treatment or processing. Fermented seeds are a specialty in Indonesia and have been used as spices. Because the tree is wild and has not been cultivated commercially, the physiology of germinated seeds of this tree for food uses is not known. This study reports some biochemical changes during seed germination associated with antioxidant activity and the mobilization of lipids and phenolics. Lipid content decreased, whereas the dominant fatty acids did not change significantly. The dominant fatty acids were oleic acid (C(18:1(n-9))) and linoleic acid (C(18:2(n-6))). During germination, oleic acid decreased while linoleic acid increased proportionally. The hypocotyl synthesized chlorophyll and the tocol composition also changed substantially. The antioxidant activity of phenolic extract increased in proportion to the total phenolics. Guaiacol peroxidase and glucose-6-phosphate dehydrogenase, selected enzymes association with phenolic metabolism, showed that the increased activities coincided with increased total phenolics and free proline. PMID:10552624
Andarwulan, N; Fardiaz, D; Wattimena, G A; Shetty, K
An extracellular lipid transfer protein is relocalized intracellularly during seed germination.
Plant lipid transfer proteins (LTPs) constitute a family of small proteins recognized as being extracellular. In agreement with this notion, several lines of evidence have shown the apoplastic localization of HaAP10, a LTP from Helianthus annuus dry seeds. However, HaAP10 was recently detected intracellularly in imbibing seeds. To clarify its distribution, immunolocalization experiments were performed during the course of germination and confirmed its intracellular localization upon early seed imbibition. Further assays using a hydrophobic dye, FM4-64, inhibitors of vesicular traffic, and immunolocalization of the pectin rhamnogalacturonan-II, allowed the conclusion that endocytosis is activated as soon as seed imbibition starts. Furthermore, this study demonstrated that HaAP10 is endocytosed throughout imbibition. Biochemical and cellular approaches indicate that the intracellular fraction of this LTP appears associated with oil bodies and some evidence also suggest its presence in glyoxysomes. So, HaAP10 is apoplastic in dry seeds and upon imbibition is rapidly internalized and relocalized to organelles involved in lipid metabolism. The results suggest that HaAP10 may be acting as a fatty acid shuttle between the oil body and the glyoxysome during seed germination. This concept is consistent with the initial proposition that LTPs participate in the intracellular transfer of lipids which was further denied based on their apparent extracellular localization. This report reveals for the first time the relocalization of a lipid transfer protein and opens new perspectives on its role. PMID:23162115
Pagnussat, Luciana; Burbach, Christian; Baluska, Frantisek; de la Canal, Laura
Effects of osmopriming on seed germination of canola (Brassica napus L.) under salinity stress.
Canola has good yield and performance in weak and saline soils that other oil crops can not be cultivated in them. Performance and production of this crop can be improved by increasing the vigor of its seeds. Priming is one of the techniques for enhancing seed vigor under stress condition. Pretreatment of seeds in osmotic solutions is called osmopriming, which is used to increase the seed moisture content and speed of germination. In this study, seeds of three varieties of canola (SLM046, Okapi and Licord) were primed in osmotic solutions and then were germinated under salinity stress at laboratory conditions. Osmotic solutions were made by polyethylene glycol 6000 in osmotic potentials of -10, -12, -14, -16 and -18 bar for 24 h. NaCl solutions with electrical conductivities of 0, 6, 12 and 18 ds/m were used to make salinity stress. Results of this study showed that osmopriming could be used to increase the performance of seeds under normal and salinity stress. PMID:17390787
Ehsanfar, S; Modarres-Sanavy, S A M; Tavakkol-Afshari, R
An Increase in Pectin Methyl Esterase Activity Accompanies Dormancy Breakage and Germination of Yellow Cedar Seeds1
Pectin methyl esterase (PME) (EC 220.127.116.11) catalyzes the hydrolysis of methylester groups of cell wall pectins. We investigated the role of this enzyme in dormancy termination and germination of yellow cedar (Chamaecyparis nootkatensis [D. Don] Spach) seeds. PME activity was not detected in dormant seeds of yellow cedar but was induced and gradually increased during moist chilling; high activity coincided with dormancy breakage and germination. PME activity was positively correlated to the degree of dormancy breakage of yellow cedar seeds. The enzyme produced in different seed parts and in seeds at different times during moist chilling, germination, and early post-germinative growth consisted of two isoforms, both basic with isoelectric points of 8.7 and 8.9 and the same molecular mass of 62 kD. The pH optimum for the enzyme was between 7.4 and 8.4. In intact yellow cedar seeds, activities of the two basic isoforms of PME that were induced in embryos and in megagametophytes following dormancy breakage were significantly suppressed by abscisic acid. Gibberellic acid had a stimulatory effect on the activities of these isoforms in embryos and megagametophytes of intact seeds at the germinative stage. We hypothesize that PME plays a role in weakening of the megagametophyte, allowing radicle emergence and the completion of germination.
Ren, Chengwei; Kermode, Allison R.
Arabinan Metabolism during Seed Development and Germination in Arabidopsis
Arabinans are found in the pectic network of many cell walls, where, along with galactan, they are present as side chains of Rhamnogalacturonan l. Whilst arabinans have been reported to be abundant polymers in the cell walls of seeds from a range of plant species, their proposed role as a storage reserve has not been thoroughly investigated. In the cell
Leonardo D. Gomez; Clare G. Steele-King; Louise Jones; Jonathan M. Foster; Supachai Vuttipongchaikij; S. J. McQueen-Mason
Bottlebrush squirreltail [Elymus elymoides (Raf.) Swezey] and big squirreltail [E. multisetus (J. G. Smith) Burtt Davy) are short lived perennial bunchgrasses found on rangelands from the Pacific Coast to the Great Plains and from Canada to Mexico. They are valuable native species seeded to suppress...
Germination of Achira Seed (Canna sp.) Approximately 550 Years Old
DURING the excavation of a tomb at the archaeological site of Santa Rosa de Tastil, Argentina (24° 25' S., 65° 50' W.), we found a necklace made out of nuts of Juglans australis. Inside each nut was a seed of Canna sp., making a rattle. Samples from bones of cameloids in the upper strata of garbage from the site were
E. Sivori; F. Nakayama; E. Cigliano
HRS1 acts as a negative regulator of abscisic acid signaling to promote timely germination of Arabidopsis seeds.
In this work, we conducted functional analysis of Arabidopsis HRS1 gene in order to provide new insights into the mechanisms governing seed germination. Compared with wild type (WT) control, HRS1 knockout mutant (hrs1-1) exhibited significant germination delays on either normal medium or those supplemented with abscisic acid (ABA) or sodium chloride (NaCl), with the magnitude of the delay being substantially larger on the latter media. The hypersensitivity of hrs1-1 germination to ABA and NaCl required ABI3, ABI4 and ABI5, and was aggravated in the double mutant hrs1-1abi1-2 and triple mutant hrs1-1hab1-1abi1-2, indicating that HRS1 acts as a negative regulator of ABA signaling during seed germination. Consistent with this notion, HRS1 expression was found in the embryo axis, and was regulated both temporally and spatially, during seed germination. Further analysis showed that the delay of hrs1-1 germination under normal conditions was associated with reduction in the elongation of the cells located in the lower hypocotyl (LH) and transition zone (TZ) of embryo axis. Interestingly, the germination rate of hrs1-1 was more severely reduced by the inhibitor of cell elongation, and more significantly decreased by the suppressors of plasmalemma H(+)-ATPase activity, than that of WT control. The plasmalemma H(+)-ATPase activity in the germinating seeds of hrs1-1 was substantially lower than that exhibited by WT control, and fusicoccin, an activator of this pump, corrected the transient germination delay of hrs1-1. Together, our data suggest that HRS1 may be needed for suppressing ABA signaling in germinating embryo axis, which promotes the timely germination of Arabidopsis seeds probably by facilitating the proper function of plasmalemma H(+)-ATPase and the efficient elongation of LH and TZ cells. PMID:22545134
Wu, Chongming; Feng, Juanjuan; Wang, Ran; Liu, Hong; Yang, Huixia; Rodriguez, Pedro L; Qin, Huanju; Liu, Xin; Wang, Daowen
HRS1 Acts as a Negative Regulator of Abscisic Acid Signaling to Promote Timely Germination of Arabidopsis Seeds
In this work, we conducted functional analysis of Arabidopsis HRS1 gene in order to provide new insights into the mechanisms governing seed germination. Compared with wild type (WT) control, HRS1 knockout mutant (hrs1-1) exhibited significant germination delays on either normal medium or those supplemented with abscisic acid (ABA) or sodium chloride (NaCl), with the magnitude of the delay being substantially larger on the latter media. The hypersensitivity of hrs1-1 germination to ABA and NaCl required ABI3, ABI4 and ABI5, and was aggravated in the double mutant hrs1-1abi1-2 and triple mutant hrs1-1hab1-1abi1-2, indicating that HRS1 acts as a negative regulator of ABA signaling during seed germination. Consistent with this notion, HRS1 expression was found in the embryo axis, and was regulated both temporally and spatially, during seed germination. Further analysis showed that the delay of hrs1-1 germination under normal conditions was associated with reduction in the elongation of the cells located in the lower hypocotyl (LH) and transition zone (TZ) of embryo axis. Interestingly, the germination rate of hrs1-1 was more severely reduced by the inhibitor of cell elongation, and more significantly decreased by the suppressors of plasmalemma H+-ATPase activity, than that of WT control. The plasmalemma H+-ATPase activity in the germinating seeds of hrs1-1 was substantially lower than that exhibited by WT control, and fusicoccin, an activator of this pump, corrected the transient germination delay of hrs1-1. Together, our data suggest that HRS1 may be needed for suppressing ABA signaling in germinating embryo axis, which promotes the timely germination of Arabidopsis seeds probably by facilitating the proper function of plasmalemma H+-ATPase and the efficient elongation of LH and TZ cells.
Wang, Ran; Liu, Hong; Yang, Huixia; Rodriguez, Pedro L.; Qin, Huanju; Liu, Xin; Wang, Daowen
Relationships Between Salt Type and Seed Germination in Three Plant Species Growing in Salt Marsh Soils of Semi-Arid Mediterranean Environments
The present work studied the germination recovery of Arthrocnemum macrostachyum, Juncus acutus, and Schoenus nigricans seeds after submersion in hypersaline solution of different salt types. Germination recovery of seed lots incubated in 1, 2, 3, 4, or 5% saline solutions of NaCl, MgCl2, MgSO4, and Na2SO4 for 30 d was studied by transferring ungerminated seeds to distilled water. Seed germination of
María José Vicente; Encarnación Conesa; José Álvarez-Rogel; José Antonio Franco; Juan José Martínez-Sánchez
Thermotolerance Is Developmentally Dependent in Germinating Wheat Seed 1
During the initial 9 to 12 hours of imbibition, the imbibing wheat (Triticum aestivum L.) seed was found to exhibit substantial tolerance to high temperature relative to later times of imbibition. Tolerance was assessed by seed viability and seedling growth. This initial high temperature tolerance gradually declines with increasing time of seed imbibition. A range of 2 hour heat pretreatments (38-42°C) prior to imposition of a 2 hour heat shock (51-53°C) during this same 9 to 12 hour interval was unable to increase survival or seedling growth over that of seed that did not receive a pretreatment. However, after 9 to 12 hours of imbibition the pretreatment provided both increased survival and increased seedling growth, measured 120 hours later, i.e., classical thermotolerance could be acquired. This response is called a `thermotolerance transition.' Isolated embryos responded in a similar manner using a 2,3,5-triphenyltetrazolium chloride assay for viability determination following heat treatments. The high temperature tolerance during early imbibition indicates that the thermotolerance transition involves the loss of an existing thermotolerance coincident with acquiring the ability to become thermotolerant following heat pretreatment. Despite the inability to acquire thermotolerance, heat shock protein synthesis was induced by heat shock immediately upon imbibition of wheat seed or isolated embryos. Developmentally regulated heat shock proteins of 58 to 60, 46, 40, and 14 kilodaltons were detected at 1.5 hours of imbibition following heat shock, but were absent or greatly reduced by 12 hours. Constitutive synthesis of 70 and 90 kilodalton hsp groups appeared to be greater at 1.5 hours of imbibition than at 12 hours of imbibition. Images Figure 2
Abernethy, Rollin H.; Thiel, David S.; Petersen, Nancy S.; Helm, Kenneth
Interacting infl uence of cold stratifi cation treatment and osmotic potential on seed germination of Triglochin maritima L
Th e eff ect of cold stratifi cation treatment and isoosmotic NaCl and polyethyleneglycol (PEG) concentrations on germination of Triglochin maritima seeds was assessed. Th e highest (400 mM) NaCl concentration caused a signifi cant decrease in germination percentage and no germination was observed at the two highest (64 and 128 mM) PEG concentrations. Th e large diff erence in
Gederts Ievinsh
Germination response of Hylocereus setaceus (Salm-Dyck ex DC: ) Ralf Bauer (Cactaceae) seeds to temperature and reduced water potentials.
The germination response of Hylocereus setaceus seeds to isothermic incubation at different water potentials was analysed by using the thermal time and hydrotime models, aiming to describe some germination parameters of the population and to test the validity of the models to describe the response of the seeds to temperature and water potential. Hylocereus setaceus seeds germinated relatively well in a wide range of temperatures and the germination was rate limited from 11 to 20 degrees C interval and beyond 30 degrees C until 40 degrees C, in which the germination rate respectively shifts positively and negatively with temperature. The minimum or base temperature (T(b)) for the germination of H. setaceus was 7 degrees C, and the ceiling temperature varied nearly from 43.5 to 59 degrees C depending on the percent fraction, with median set on 49.8 degrees C. The number of degrees day necessary for 50% of the seeds to germinate in the infra-optimum temperature range was 39.3 degrees C day, whereas at the supra-optimum interval the value of theta = 77 was assumed to be constant throughout. Germination was sensitive to decreasing values of psi in the medium, and both the germinability and the germination rate shift negatively with the reduction of psi, but the rate of reduction changed with temperature. The values of base water potential (psi(b)) shift to zero with increasing temperatures and such variation reflects in the relatively greater effect of low psi on germination in supra optimum range of T. In general, the model described better the germination time courses at lower than at higher water potentials. The analysis also suggest that Tb may not be independent of psi and that psi(b(g)) may change as a function of temperature at the infra-otimum temperature range. PMID:20231970
Simăo, E; Takaki, M; Cardoso, V J M
Seed reserve composition in 19 tree species of a tropical deciduous forest in Mexico and its relationship to seed germination and seedling growth
Background and Aims The size and composition of seed reserves may reflect the ecological strategy and evolutionary history of a species and also temporal variation in resource availability. The seed mass and composition of seed reserves of 19 co-existing tree species were studied, and we examined how they varied among species in relation to germination and seedling growth rates, as well as between two years with contrasting precipitation (652 and 384 mm). Methods Seeds were collected from a tropical deciduous forest in the northwest of Mexico (Chamela Biological Station). The seed dry mass, with and without the seed coat, and the concentrations of lipids, nitrogen and non-structural carbohydrates for the seed minus seed coat were determined. The anatomical localization of these reserves was examined using histochemical analysis. The germination capacity, rate and lag time were determined. The correlations among these variables, and their relationship to previously reported seedling relative growth rates, were evaluated with and without phylogenetic consideration. Key Results There were interannual differences in seed mass and reserve composition. Seed was significantly heavier after the drier year in five species. Nitrogen concentration was positively correlated with seed coat fraction, and was significantly higher after the drier year in 12 species. The rate and lag time of germination were negatively correlated with each other. These trait correlations were also supported for phylogenetic independent contrasts. Principal component analysis supported these correlations, and indicated a negative association of seedling relative growth rate with seed size, and a positive association of germination rate with nitrogen and lipid concentrations. Conclusions Nitrogen concentration tended to be higher after the drier year and, while interannual variations in seed size and reserve composition were not sufficient to affect interspecific correlations among seed and seedling traits, some of the reserves were related to germination variables and seedling relative growth rate.
Soriano, Diana; Orozco-Segovia, Alma; Marquez-Guzman, Judith; Kitajima, Kaoru; Gamboa-de Buen, Alicia; Huante, Pilar
Involvement of the abscisic acid catabolic gene CYP707A2 in the glucose-induced delay in seed germination and post-germination growth of Arabidopsis.
Earlier studies showed that sugars as signaling molecules play pivotal roles in the regulation of seed germination. ABA biosynthesis upregulation is suggested as one of the possible mechanisms mediating the glucose-induced delay in seed germination. In this study, the role of ABA catabolism in glucose-induced inhibition was investigated. Using Arabidopsis thaliana seeds, the results show that the repression of ABA catabolism by diniconazole aggravated the glucose-induced delay in seed germination. The transcript and protein profiles of CYP707A2, a key gene encoding ABA 8'-hydroxylase in ABA catabolism in Arabidopsis, were significantly decreased by exogenous glucose treatment. Transgenic experiments confirmed that the over-expression of the CYP707A2 gene alleviated the glucose-induced inhibition effect, whereas the cyp707a2 mutant seeds displayed a hypersensitivity to glucose during imbibition. Exogenous glucose also arrested the early seedling development of Arabidopsis. The CYP707A2 over-expression seedlings exhibited lower ABA levels and seemed less sensitive to exogenous glucose compared with wild type seedlings. In summary, the glucose-induced delay in seed germination and seedling development is directly related to the suppression of ABA catabolism through the repression of the CYP707A2 expression. PMID:21883251
Zhu, Guohui; Liu, Yinggao; Ye, Nenghui; Liu, Rui; Zhang, Jianhua
Subcellular analysis of starch metabolism in developing barley seeds using a non-aqueous fractionation method.
Compartmentation of metabolism in developing seeds is poorly understood due to the lack of data on metabolite distributions at the subcellular level. In this report, a non-aqueous fractionation method is described that allows subcellular concentrations of metabolites in developing barley endosperm to be calculated. (i) Analysis of subcellular volumes in developing endosperm using micrographs shows that plastids and cytosol occupy 50.5% and 49.9% of the total cell volume, respectively, while vacuoles and mitochondria can be neglected. (ii) By using non-aqueous fractionation, subcellular distribution between the cytosol and plastid of the levels of metabolites involved in sucrose degradation, starch synthesis, and respiration were determined. Wit