Erythroxylum novogranatense
Introduction '''''Erythroxylum novogranatense''''' is a neotropical species of ''Erythroxylum'' (Erythroxylaceae). Cocaine is produced from the leaves.
Name "Novogranatense" is derived from Latin: ''novo'' (new) and ''granatense'' (Granada). It was named by William Turner Thiselton-Dyer, the third director of Royal Botanic Gardens, Kew, because its country of origin was the Spanish colonial Viceroyalty of New Granada—present day Colombia.
Subspecies ''Erythroxylum novogranatense'' contains 2 subspecies:*''Erythroxylum novogranatense'' var. ''novogranatense'' (D.Morris) Hieron*''Erythroxylum novogranatense'' var. ''truxillense'' (Rusby) PlowmanThese two subspecies are phenotypically similar, but morphologically distinguishable.
Taxonomy Among the genus ''Erythroxylum'', cocaine-rich leaves are obtained from 4 taxa: *''Erythroxylum coca'' var. ''coca''*''Erythroxylum coca'' var. ''ipadu''*''Erythroxylum novogranatense'' var. ''novogranatense''*''Erythroxylum novogranatense'' var. ''truxillense''''Erythroxylum novogranatense'' was originally identified as ''E. coca'', subsequently described as a variety, and finally came to be recognized as its own species. ''Erythroxylum novogranatense'' var. ''novogranatense'' is native to Colombia and Venezuela. Unlike ''Erythroxylum coca'', it tolerates non-acidic soils. Its adaptability and easy propagation has led to a wide distribution over the Old World and New World tropics. It was introduced in Bogor (West Java, Indonesia) in 1875, and by 1888 large quantities of seed were already being distributed in South-East Asia. It has been grown in Peninsular Malaysia, western and eastern Java (Indonesia), northern Borneo (Indonesia), northern Sulawesi (Indonesia) and the Philippines (Luzon).
Cocaine content In an extensive study, the cocaine content in leaves of ''E. coca'' var. ''coca'' (30 samples) was found to range from 0.23-0.96%, with a mean of 0.63%, while the cocaine content in ''E. coca'' var. ''ipadu'' (6 samples) was lower: 0.11-0.41%, with an average of 0.25%. ''E. novogranatense'' var. ''novogranatense'' (3 samples) contained 0.55-0.93% cocaine, with an average of 0.77% and ''E. novogranatense'' var. ''truxillense'' (14 samples) 0.42-1.02%, with a mean of 0.72%.
Ecology ''Erythroxylum novogranatense'' is a highland variety that is utilized in lowland areas. It is cultivated in drier regions in South America, where it requires irrigation. However, ''E. novogranatense'' is very adaptable to varying ecological conditions, and grows well in both humid and dry areas, and at low and higher altitudes. In Java (Indonesia), ''E. novogranatense'' has been cultivated from sea-level to  altitude, with best results at .In controlled environment studies, the optimum average daily temperature for leaf growth for ''E. novogranatense'' var. ''novogranatense'' was found to be around , whereas leaf growth was generally higher at photosynthetic photon flux densities (PPFD) of 250 or 400 micromol per meter square per second than at 155 micromol per meter square per second. Environmental effects on the cocaine concentration in the leaves were smaller, so that total cocaine production per plant was largely a function of leaf mass, with environmental conditions that stimulated leaf growth giving higher cocaine yields. Both species grow on soils with low pH, and a greenhouse study has shown that the optimum pH for biomass accumulation of ''E. novogranatense'' is between 4.7 and 6.0.
Propagation and planting ''Erythroxylum novogranatense'' var. ''novogranatense'', ''E. novogranatense'' var. ''truxillense'' and ''E. coca'' var. ''coca'' have to be reproduced by seed, because vegetative propagation is difficult. However, ''E. coca'' var. ''ipadu'' does not produce seed and is produced by stem cuttings. It cannot reproduce without human interference. Cultivated ''E. novogranatense'' var. ''novogranatense'' produces abundant seed and is easy to propagate. Seed viability decreases rapidly. Germination percentages of ''E. coca'' and ''E. novogranatense'' seed were found to decrease from around 95% and 89% directly after harvesting to 29% and 0%, respectively, after 24 days of storage at . Coca seedlings are usually sown in shaded nurseries and transplanted to the field when they are about one year old and  tall. In the field, they are planted at a spacing of . The actual time of transplanting and the spacing of the plants varies with climatic factors and whether coca is interplanted or cultivated as a sole crop.Coca farmers in South America, when collecting their seeds, pour them into a container of water; the seeds that float are discarded as they are non-viable.
Identification ''Erythroxylum novogranatense'' var. ''truxillense'' flowerThe basic physical difference between ''E. coca'' and ''E. novogranatense'' is that the ''E. coca'' (sometimes called ''E. bolivianum'') has larger leaves that are elliptical, oval and broader near the middle (broad-elliptic) and darker green color above. The ''E. novogranatense'' has smaller, narrower leaves, broadest near the apex (oblong-obovate), and bright green color above. To identify ''E. novogranatense'' var. ''novogranatense'' from ''E. novogranatense'' var. ''truxillense'': The leaves of ''E. novogranatense'' var. ''truxillense'' does not possess parallel lines either side of the central vein like all other varieties.
Harvesting The first harvest of coca takes place at 1–3 years after transplanting. In the Island of Java (Indonesia), a first harvest can be expected within a year after transplanting. The leaves have to be stiff and easily detachable to be harvested. Leaves can be harvested every 50–60 days in the rainy season, but when it is drier, they are usually harvested every 3–4 months. The leaves should be pinched from the plant, not ripped off.
References * Plant Resources of South-East Asia 12(3) Medicinal and Poisonous Plants 3: R.H.M.J. Lemmens, N. Bunyapraphatsara (Eds. ); Backhuys Publishers, Leiden, 2003, 664 pages,
Further reading
External links * The Dutch Colonial Coca Boom, 1905-1930