horizontal resistance, race non-specific resistance) genotype germ theory giant cell girdle giant cells gram-negative Gram-negative bacteria are those that do not retain crystal violet dye in the Gram staining protocol. gram-positive Gram-positive bacteria are classified as bacteria that retain a crystal violet dye during the Gram stain process. gram stain growth regulator (syn. hormone) gummosis (pl. gummoses) H haploid hardiness haustorium (pl. haustoria) The haustorium is the hyphal tip of a parasitic fungus hemiparasite hermaphrodite (adj. hermaphroditic) heteroecious heterokaryon (adj. heterokaryotic) heterothallic heterotroph holomorph holoparasite homokaryon (adj. homokaryotic) homothallism (adj. homothallic) horizontal resistance (syn. general resistance, race non-specific resistance) host plant host range hyaline hymenium hyperparasite hyperplasia hypertrophy hypersensitive hypersensitive reaction and pathogenicity (hrp) gene hypersensitive response (HR) hypha hyphal sheath (syn. mantle) hyphomycetes hyphopodium hypoplasia hypovirulence hypovirulence is reduced virulence of a pathogen. Hypovirulence in fungi can be caused by a virus within the fungus. The virus reduces virulence and sporulation. A hypovirus-fungus can be used in biological control. I immune immunity imperfect fungi (syn. Fungi Imperfecti, deuteromycetes) imperfect state (syn. anamorph) in planta in situ in vitro in vivo incubation period indicator plant indirect penetration induced induced systemic resistance (ISR) infection court infection cushion infection focus infection peg (syn. penetration peg) infection period infectious infective infest (n. infestation) initial inoculum (syn. primary inoculum) injury inoculate (n. inoculation) inoculum (pl. inocula) inoculum density integrated pest management (abbr. IPM) intumescence (syn. edema or oedema) IPM (abbr. for integrated pest management) isolate K klendusity The disease-escaping ability of plants. Koch's postulates knot L latent infection latent period leaf dip leaf spot leafroll lesion life cycle lignification local lesion local necrosis lodge M macerate macroconidium (pl. macroconidia) macrocyclic macronutrient mantle (syn. hyphal sheath) mating types mechanical injury mechanical transmission medium (pl. media) melanin microbial microclimate microconidium (pl. microconidia) microcyclic microflora micronutrient microorganism (syn. microbe) microsclerotium mildew MLO (syn. mycoplasmalike organism) mold mollicute monocyclic monoecious monogenic monogenic resistance (syn. single gene resistance) monotrichous monoxenic culture mosaic motile mottle movement protein multigenic resistance (syn. polygenic resistance) multiline multinucleate multiparticulate virus multipartite virus multiseptate mummification mummy mushroom mutagen Mycelia sterilia mycelium (pl. mycelia) Mycelium is the vegetative part of a fungus consisting of a mass of branching, threadlike hyphae that exists below the ground or within another substrate. mycology mycoparasite mycoplasmalike organism (syn. MLO) mycorrhiza (pl. mycorrhizae; adj. mycorrhizal) mycotoxin mycovirus Myxomycetes (syn. slime molds) N necrosis (adj. necrotic) necrotroph needle cast (of conifers) nematicide