Editing Erythroxylum coca

{{Short description|Species of flowering plant}}
{{Speciesbox
|name = Coca
|image = Koeh-204.jpg
|genus = Erythroxylum
|species = coca
|authority = [[Jean-Baptiste Lamarck|Lam.]]
}}

'''''Erythroxylum coca''''' is one of two species of cultivated [[coca]].

==Description==
The coca plant resembles a [[blackthorn]] bush, and grows to a height of {{convert|2|–|3|m|ft|abbr=on|sigfig=1}}. The branches are straight, and the leaves, which have a green tint, are thin, opaque, oval, and taper at the extremities. A marked characteristic of the leaf is an areolated portion bounded by two longitudinal curved lines, one line on each side of the midrib, and more conspicuous on the underside of the leaf. Coca plants are mainly found in Colombia. 

The flowers are small, and disposed in little clusters on short stalks; the [[corolla (botany)|corolla]] is composed of five yellowish-white [[petal]]s, the [[anther]]s are heart-shaped, and the [[pistil]] consists of three [[carpel]]s united to form a three-chambered [[ovary (botany)|ovary]]. The flowers mature into red [[Berry (botany)|berries]].

Unlike ''Erythroxylum novogranatense'', ''Erythroxylum coca'' requires very acidic soil conditions. Soil acidity and water acidity need to be below [[pH]] 5.5, with the optimal value being pH 3.5, similar to that of ''[[Rhododendron]]'' [[potting soil]]s. At pH 6.5 and above, [[chlorosis]] and leaf distortion occur.<ref>{{cite journal |last1=Johnson |first1=Emanuel L. |last2=Campbell |first2=T. Austin |last3=Foy |first3=Charles D. |title=Effect of soil pH on mineral element concentrations of two erythroxylum species |journal=Journal of Plant Nutrition |date=November 1997 |volume=20 |issue=11 |pages=1503–1515 |doi=10.1080/01904169709365352}}</ref>

The leaves are sometimes eaten by the [[larva]]e of the [[moth]] ''[[Eloria noyesi]]''.

Of the two cultivated species of coca, ''Erythroxylum coca'' has greater resistance to the use of glyphosate as an herbicide than ''Erythroxylum novogranatense''.<ref>{{cite journal |last1=Ferreira |first1=Jorge F. S. |last2=Smeda |first2=Reid J. |last3=Duke |first3=Stephen O. |title=Control of Coca Plants (Erythroxylum coca and E. novogranatense) with Glyphosate |journal=Weed Science |date=August 1997 |volume=45 |issue=4 |pages=551–556 |doi=10.1017/S0043174500088809}}</ref>

==Taxonomy==
{{Further|Coca#Species and evolution}}
Among the genus ''[[Erythroxylum]]'', [[cocaine]]-rich leaves are obtained from four taxa:
* ''Erythroxylum coca'' var. ''coca''
* ''Erythroxylum coca'' var. ''ipadu''
* ''[[Erythroxylum novogranatense]]'' var. ''novogranatense''
* ''Erythroxylum novogranatense'' var. ''truxillense''

==Amazonian coca==
''Erythroxylum coca'' var. ''ipadu'', also known as Amazonian coca, is closely related to ''Erythroxylum coca'' var. ''coca'', from which it originated relatively recently.<ref name="Plowman1979">Plowman T.  "Botanical Perspectives on Coca."  Journal of Psychedelic Drugs.  1979.  11(1-2): 103-117.</ref> ''E. coca'' var. ''ipadu'' does not escape cultivation or survive as a feral or wild plant like ''E. coca'' var. ''coca'' <ref name="Plowman1984">Plowman T.  "The Origin, Evolution, and Diffusion of Coca, Erythroxylum spp., in South and Central America."  In: Stone D, ed. Pre-Columbian Plant Migration.  Papers of the Peabody Museum of Archaeology and Ethnology.  Harvard University. Vol 76.  Cambridge MA: Harvard University Press; 1984. p. 125-163.</ref>  It has been suggested that due to a lack of genetic isolation to differentiate it from ''E. coca'' var. ''coca'', ''E. coca'' var. ''ipadu'' may be better defined as a distinct cultivar than a taxonomic variety.<ref name="Bohm1982">Bohm B, Ganders F, Plowman T.  Biosystematics and Evolution of Cultivated Coca (Erythroxylaceae).  Systematic Botany. 1982; 7(2): 121-133.</ref>

Unlike the other species of [[coca]] which are propagated through seeds, ''E. coca'' var. ''ipadu'', which rarely produce seeds, is propagated through stem cuttings which remain viable for several weeks if kept moist.<ref name="Plowman1984" /> Since Amazonian coca is vegetatively propagated, entire plantations may be populated from the same clone.  ''E. coca'' var. ''ipadu'' is specially adapted to the shifting agriculture of semi-nomadic Amazonian peoples.  Since cuttings of ''E. coca'' var. ''coca'' do not easily root, it is likely that ''E. coca'' var. ''ipadu'' has been artificially selected for its ease of vegetative propagation.<ref name="Plowman1984" />
In contrast to the Andean ''E. coca'' var. ''coca'', Amazonian ''E. coca'' var. ''ipadu'' is typically a weaker plant evidenced by the fact that after a few years plants lose their vigor and easily fall prey to disease or insect infestation. Overharvesting can speed up this process.<ref name="Plowman1981" >Plowman T.  Amazonian Coca.  Journal of Ethnopharmacology. 1981. 3: 195 - 225.</ref>

Amazonian coca is prepared differently than the other three cultivated cocas. After fire-toasting the leaves dry, they are pulverized. Once sifted, the powder is combined with ashes from plants which serve as the necessary alkaline admixture for coca chewing.<ref name="Plowman1981" />

== See also ==
* [[Coca alkaloid]]s

== References ==
=== Citations ===
{{Reflist}}

=== Sources ===
{{Refbegin}}
* Turner C. E., Elsohly M. A., Hanuš L., Elsohly H. N. Isolation of dihydrocuscohygrine from Peruvian coca leaves. Phytochemistry 20 (6), 1403-1405 (1981)
* ''History of Coca. The Divine Plant of the Incas'' by W. Golden Mortimer, M.D. 576 pp. And/Or Press San Francisco, 1974. This title has no ISBN.
* {{EB1911|wstitle=Coca|volume=6|pages=614–615}}
{{Refend}}

== External links ==
{{Commons and category|Erythroxylum coca|Erythroxylum_coca}}
{{Wikispecies|Erythroxylum coca}}
* [https://www.tni.org/en/primer/coca-leaf-myths-and-reality Coca leaf: Myths and Reality] website of the Transnational Institute (TNI)
* [https://www.tni.org/en/collection/coca-leaf Unscheduling the coca leaf], UN Drug Control website of the Transnational Institute (TNI)
* [http://historyofalcoholanddrugs.typepad.com/alcohol_and_drugs_history/coca_leaf/index.html Coca leaf news page] – [[Alcohol and Drugs History Society]]
* [http://www.weberseeds.de/files/erythroxylum_coca_08.jpg Erythroxylum coca flower closeup]

{{Taxonbar|from=Q158018}}
{{Authority control}}

[[Category:Erythroxylum|coca]]
[[Category:Flora of the Andes]]
[[Category:Flora of the Amazon]]
[[Category:Flora of western South America]]
[[Category:Crops originating from the Americas]]
[[Category:Medicinal plants of South America]]
[[Category:Taxa named by Jean-Baptiste Lamarck]]
[[Category:Coca]]
[[Category:Culture of Bolivia]]