Cannabis
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/* Various strains of cannabis */ copyedit
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{{otheruses4|the plant genus ''Cannabis''|use as a psychoactive drug|Cannabis (drug)}}
{{Taxobox
| name = Cannabis
| image = Cannabis sativa Koehler drawing.jpg
| image_width = 250px
| image_caption = common hemp
| regnum = [[Plant]]ae
| divisio = [[Flowering plant|Magnoliophyta]]
| classis = [[Magnoliopsida]]
| ordo = [[Rosales]]
| familia = [[Cannabaceae]]
| genus = '''''Cannabis'''''
| genus_authority = [[Carolus Linnaeus|L.]]
| subdivision_ranks = Species
| subdivision =
'''''Cannabis sativa'' subsp. ''indica''''' L.<ref name="grin">
{{cite web
|url=http://www.ars-grin.gov/cgi-bin/npgs/html/taxon.pl?8862
|title=Cannabis sativa information from NPGS/GRIN
|publisher=www.ars-grin.gov
|accessdate=2008-07-13
|last=
|first=
}}
</ref><br />
'''''Cannabis sativa'' subsp. ''sativa''''' Lam.<ref name="grin"/><br />
'''''Cannabis ruderalis Janisch.'''''
}}
[[Image:Hash museum amsterdam.JPG|thumb|right|220px|Cannabis Museum in Amsterdam]]
'''''Cannabis''''' (''[[Syllable stress of Botanical Latin|Cán-na-bis]]'') is a [[genus]] of [[flowering plant]]s that includes three putative species, ''Cannabis sativa'' subsp. ''indica'' L.,<ref name="grin"/> ''Cannabis sativa'' subsp. ''sativa'' Lam.,<ref name="grin"/> and ''Cannabis ruderalis'' Janisch. These three taxa are [[indigenous]] to [[central Asia]] and surrounding regions. Cannabis has long been used for fibre ([[hemp]]), for [[medical cannabis|medicinal purposes]], and as a [[cannabis (drug)|psychoactive]]. Industrial [[hemp]] products are made from ''Cannabis'' plants selected to produce an abundance of fiber and minimal levels of [[THC]] (Δ<sup>9</sup>- tetrahydrocannabinol), one [[psychoactive]] molecule that produces the "high" associated with [[cannabis (drug)|marijuana]]. The drug consists of dried flowers and leaves of plants selected to produce high levels of THC. Various extracts including [[hashish]] and hash oil are also produced.<ref name=erowid>Erowid. 2006. [http://www.erowid.org/plants/cannabis/cannabis_basics.shtml ''Cannabis'' Basics]. Retrieved on 25 Feb 2007</ref> The cultivation and possession of ''Cannabis'' for recreational use is outlawed in most countries.
== Etymology ==
{{main|Cannabis (etymology)}}
The plant name '''cannabis''' is from [[Ancient Greek|Greek]] '''{{lang|grc|κάνναβις}}''' (''{{lang|grc|kánnabis}}''), via [[Latin]] ''{{lang|la|cannabis}}'', a [[Scythian languages|Scythian]] or [[Thracian language|Thracian]] word, also loaned into [[Persian language|Persian]] as ''{{lang|fa|kanab}}''. English ''[[hemp]]'' (Old English {{lang|ags|hænep}}) may be an early loan (predating [[Grimm's Law]]) from the same source. In [[Hebrew language|Hebrew]], the word is ''קַנַּבּוֹס'' [qan:a'bos]. It is found in Exodus 30:22-29 as a constituent of the [[Spiritual use of cannabis|anointing oil]]) and Old Akkadian ''qunnabtu'', Neo-[[Assyrian]] and Neo-[[Babylonian]] ''qunnabu'' were used to refer to the plant.<ref>{{Citation
| last =
| first =
| author-link =
| last2 =
| first2 =
| author2-link =
| year =1976
| date =
| publication-date =
| contribution =
| contribution-url =
| editor-last =Rubin
| editor-first =Vera
| editor-link =
| title =Cannabis and Culture
| edition =
| series =
| place =The Hague
| publication-place =
| publisher =Mouton
| volume =
| pages =305
| id =
| isbn =9027976694
| doi =
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}}</ref><ref>{{Citation
| last =
| first =
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| last2 =
| first2 =
| author2-link =
| year =1999
| date =
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| contribution =
| contribution-url =
| editor-last =Black
| editor-first =Jeremy
| editor-link =
| editor2-last =George
| editor2-first =Andrew
| editor2-link =
| editor3-first=Postgate
| editor3-last=Nicholas
| title =A Concise Dictionary of Akkadian
| edition =
| series =SANTAG
| volume =5
| place =
| publication-place =Wiesbaden
| publisher =Harrassowitz Verlag
| pages =
| id =
| isbn =3-447-04225-7
| doi =
| oclc =
| url =
}}</ref>
The further origin of the Scythian term is uncertain.
== Description ==
''Cannabis'' is an [[Annual plant|annual]], [[dioecious]], [[Flowering plant|flowering]] [[herb]]. The [[leaf|leaves]] are [[Leaf shape|palmately compound]], with [[serrate]] [[leaflet]]s. The first pair of leaves usually have a single leaflet, the number gradually increasing up to a maximum of about thirteen leaflets per leaf (usually seven or nine), depending on variety and growing conditions. At the top of a flowering plant, this number again diminishes to a single leaflet per leaf. The lower leaf pairs usually occur in an opposite [[Phyllotaxis|leaf arrangement]] and the upper leaf pairs in an alternate arrangement on the main stem of a mature plant.
''Cannabis'' usually has [[Plant sexuality#Terminology|imperfect]] [[flowers]] with [[Stamen|staminate]] "male" and [[pistil]]late "female" flowers occurring on separate plants,<ref name=”lebel1997”>Lebel-Hardenack, S. and S. R. Grant. 1997. Genetics of sex determination in flowering plants. ''Trends in Plant Science'' '''2'''(4): 130–136.</ref> although [[Hermaphrodite#In plants|hermaphroditic]] plants sometimes occur.<ref name="moliterni2005">Cristiana Moliterni, V. M., L. Cattivelli, P. Ranalli. and G. Mandolino. 2005. [http://www.springerlink.com/content/t491042240h422v8/?p=702c2acbac6445a095ebaf968bca427d&pi=11 The sexual differentiation of ''Cannabis sativa'' L.: A morphological and molecular study]. ''Euphytica'' '''140'''(1-2): 95-106. Retrieved on 25 Feb 2007</ref> Male flowers are borne on loose [[panicle]]s, and female flowers are borne on [[raceme]]s.<ref name="bouquet1950"> Bouquet, R. J. 1950. [http://www.unodc.org/unodc/bulletin/bulletin_1950-01-01_4_page003.html ''Cannabis'']. United Nations Office on Drugs and Crime. Retrieved on 23 Feb 2007</ref> It is not unusual for individual plants to bear both male and female flowers, though these are referred to as 'intersexual' or hermaphroditic rather than monoecious, since staminate and pistillate structures appear at different points on the plant, not within the same flower.
[[Cannabinoids]], [[terpenoids]], and other compounds are secreted by glandular [[trichomes]] that occur most abundantly on the floral [[sepal|calyxes]] and [[bract]]s of female plants.<ref name="mahlberg2001a">Mahlberg, Paul G. and Eun Soo Kim. 2001. [http://www.hempreport.com/issues/17/malbody17.html THC (tetrahyrdocannabinol) accumulation in glands of ''Cannabis'' (Cannabaceae)]. ''The Hemp Report'' '''3'''(17). Retrieved on 23 Feb 2007</ref>
All known strains of ''Cannabis'' are [[Anemophily|wind-pollinated]]<ref name="clarke1991a">Clarke, Robert C. 1991. ''Marijuana Botany'', 2nd ed. Ron Publishing, California. ISBN 0-914171-78-X</ref> and produce "[[seed]]s" that are technically called [[achene]]s.<ref name="small1975c">Small, E. 1975. Morphological variation of achenes of ''Cannabis''. ''Canadian Journal of Botany'' '''53'''(10): 978-987.</ref> Most strains of ''Cannabis'' are [[short day plant]]s,<ref name=clarke1991a/> with the possible exception of ''C. sativa'' subsp. ''sativa'' var. ''spontanea'' (= ''C. ruderalis''), which is commonly described as "auto-flowering" and may be [[Day neutral plant|day-neutral]].
''Cannabis'' is naturally [[Ploidy|diploid]], having a [[chromosome]] complement of 2n=20, although polyploid individuals have been artificially produced.<ref name=”small1972a”>Small, E. 1972. Interfertility and chromosomal uniformity in ''Cannabis''. ''Canadian Journal of Botany'' '''50'''(9): 1947-1949.</ref>
Cannabis is a genus of flowering plant which includes one or more species. The plant is believed to have originated in the mountainous regions just north west of the Himalayas. It is also known as hemp, although this term usually refers to varieties of Cannabis cultivated for non-drug use. Cannabis plants produce a group of chemicals called cannabinoids which produce mental and physical effects when consumed. As a drug it usually comes in the form of dried buds or flowers ([[cannabis (drug)|marijuana]]), [[resin]] ([[hashish]]), or various extracts collectively known as [[hashish oil]].<ref name=erowid/> In the early 20th century, it became illegal in most of the world to cultivate or possess Cannabis for drug purposes.
== Taxonomy ==
[[Image:Marijuana.jpg|thumb|right|Leaf of a ''Cannabis'' plant.]]
The genus ''Cannabis'' was formerly placed in the [[Nettle]] ([[Urticaceae]]) or [[Mulberry]] ([[Moraceae]]) family, but is now considered along with [[Hop (plant)|hops]] (''Humulus'' sp.) to belong to the [[Hemp]] family ([[Cannabaceae]]).<ref name=schultes2001a>Schultes, R. E., A. Hofmann, and C. Rätsch. 2001. The nectar of delight. In: ''Plants of the Gods'' 2nd ed., Healing Arts Press, Rochester, Vermont, pp. 92-101. ISBN 0-89281-979-0</ref> Recent [[phylogenetic]] studies based on [[cpDNA]] [[restriction site]] analysis and [[gene sequencing]] strongly suggest that the Cannabaceae arose from within the [[Celtidaceae]] [[clade]], and that the two families should be merged to form a single [[monophyletic]] group.<ref name=song2001>Song, B.-H., Wang, X.-Q., Li, F.-Z., and Hong, D.-Y. 2001. [http://springerlink.metapress.com/content/9v01xfaw7t8qx288/?p=db82cdfc53554cc687fd999a5c7e371f&pi=8 Further evidence for paraphyly of the Celtidaceae from the chloroplast gene ''matK'']. ''Plant Systematics and Evolution'' '''228'''(1-2): 107-115.</ref><ref name=sytsma2002>Sytsma, K. J., Morawetz, J., Pires, J. C., Nepokroeff, M., Conti, E., Zjhra, M., Hall, J. C., and Chase, M. W. 2002. [http://www.amjbot.org/cgi/content/abstract/89/9/1531 Urticalean Rosids: circumscription, Rosid ancestry, and phylogenetics based on ''rbcL'', ''trnL-F'', and ''ndh-F'' sequences]. ''American Journal of Botany'' '''89'''(9): 1531-1546.</ref>
Various types of ''Cannabis'' have been described, and classified as [[species]], [[subspecies]], or [[Variety (biology)|varieties]]:<ref name="small1975b">Small, Ernest. 1975. [http://www.unodc.org/unodc/bulletin/bulletin_1975-01-01_3_page002.html American law and the species problem in ''Cannabis'': Science and semantics]. ''Bulletin on Narcotics'' '''27'''(3): 1-20. Retrieved on 23 Feb 2007</ref>
*plants cultivated for fiber and seed production, described as low-intoxicant, non-drug, or fiber types
*plants cultivated for drug production, described as high-intoxicant or drug types
*escaped or wild forms of either of the above types.
''Cannabis'' plants produce a unique family of terpeno-phenolic compounds called cannabinoids, which produce the "high" one experiences from smoking marijuana. The two cannabinoids usually produced in greatest abundance are cannabidiol ([[Cannabidiol|CBD]]) and/or Δ<sup>9</sup>-tetrahydrocannabinol ([[THC]]), but only THC is psychoactive. Since the early 1970s, ''Cannabis'' plants have been categorized by their chemical [[phenotype]] or "chemotype," based on the overall amount of THC produced, and on the ratio of THC to CBD.<ref name="small1973a">Small, E. and H. D. Beckstead. 1973. Common cannabinoid phenotypes in 350 stocks of ''Cannabis''. ''Lloydia'' '''36''': 144–165.</ref> Although overall [[cannabinoid]] production is influenced by environmental factors, the THC/CBD ratio is genetically determined and remains fixed throughout the life of a plant.<ref name="meijer2003a">Etienne P. M. de Meijer, M. Bagatta, A. Carboni, P. Crucitti, V. M. Cristiana Moliterni, P. Ranalli, and G. Mandolino. 2003. [http://www.genetics.org/cgi/content/abstract/163/1/335 The Inheritance of Chemical Phenotype in ''Cannabis sativa'' L.] ''Genetics'' '''163'''(1): 335-346. Retrieved on 23 Feb 2007</ref> Non-drug plants produce relatively low levels of THC and high levels of CBD, while drug plants produce high levels of THC and low levels of CBD. When plants of these two chemotypes cross-pollinate, the plants in the first filial (F<sub>1</sub>) generation have an intermediate chemotype and produce similar amounts of CBD and THC. Female plants of this chemotype may produce enough THC to be utilized for drug production.<ref name=small1973a/><ref name="hillig2004a">Hillig, Karl W. and Paul G. Mahlberg. 2004. [http://www.amjbot.org/cgi/content/abstract/91/6/966 A chemotaxonomic analysis of cannabinoid variation in ''Cannabis'' (Cannabaceae)]. ''American Journal of Botany'' '''91'''(6): 966-975. Retrieved on 22 Feb 2007</ref>
[[Image:Cannabis-vegetative-growth-00003.jpg|right|thumb|Top of ''Cannabis'' plant in vegetative growth stage.]]
Whether the drug and non-drug, cultivated and wild types of ''Cannabis'' constitute a single, highly variable species, or the genus is polytypic with more than one species, has been a subject of debate for well over two centuries. This is a contentious issue because there is no universally accepted definition of a [[species]].<ref name=”small1979a”>Small, E. 1979. Fundamental aspects of the species problem in biology. In: ''The Species Problem in Cannabis'', vol. 1: Science. Corpus Information Services, Toronto, Canada, pp. 5-63. ISBN 0-919217-11-7</ref> One widely applied criterion for species recognition is that species are "groups of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups."<ref name="glossary">Rieger, R., A. Michaelis, and M. M. Green. 1991. ''Glossary of Genetics'', 5th ed. Springer-Verlag, pp. 458-459. ISBN 0-387-52054-6</ref> Populations that are physiologically capable of interbreeding, but morphologically or genetically divergent and isolated by geography or ecology, are sometimes considered to be separate species.<ref name=glossary/> [[Reproductive isolation|Physiological barriers to reproduction]] are not known to occur within ''Cannabis'', and plants from widely divergent sources are interfertile.<ref name=”small1972a”>Small, E. 1972. Interfertility and chromosomal uniformity in ''Cannabis''. ''Canadian Journal of Botany'' '''50'''(9): 1947-1949.</ref> However, physical barriers to gene exchange (such as the Himalayan mountain range) might have enabled ''Cannabis'' gene pools to diverge before the onset of human intervention, resulting in speciation.<ref name=”hillig2005a”>Hillig, Karl W. 2005. [http://www.ingentaconnect.com/content/klu/gres/2005/00000052/00000002/00004452 Genetic evidence for speciation in ''Cannabis'' (Cannabaceae)]. ''Genetic Resources and Crop Evolution'' '''52'''(2): 161-180. Retrieved on 23 Feb 2007</ref> It remains controversial whether sufficient morphological and genetic divergence occurs within the genus as a result of geographical or ecological isolation to justify recognition of more than one species.<ref name="small1975a"> Small, E. 1975. [http://www.botany.org/PlantScienceBulletin/psb-1975-21-3.php On toadstool soup and legal species of marihuana]. ''Plant Science Bulletin'' '''21'''(3): 34-39. Retrieved on 23 Feb 2007</ref><ref name="emboden1981a">Emboden, W. A. 1981. The genus ''Cannabis'' and the correct use of taxonomic categories. ''Journal of Psychoactive Drugs'' '''13''': 15–21.</ref><ref name="schultes1980a">Schultes, R. E., and A. Hofmann. 1980. ''Botany and Chemistry of Hallucinogens''. C. C. Thomas, Springfield, Illinois, pp. 82–116. ISBN 0-398-03863-5</ref>
=== Early classifications ===
[[Image:Cannab2 new.png|thumb|right|225px|Relative size of types of cannabis]]
The ''Cannabis'' genus was first [[Scientific classification|classified]] using the "modern" system of taxonomic [[Binomial nomenclature|nomenclature]] by [[Carolus Linnaeus]] in 1753, who devised the system still in use for the naming of species.<ref name="linnaeus1753">Linnaeus, C. 1753. ''Species Plantarum'' '''2''': 1027. Salvius, Stockholm. [Facsimile edition, 1957-1959. Ray Society, London, U.K.]</ref> He considered the genus to be monotypic, having just a single species that he named ''Cannabis sativa'' L. (L. stands for Linnaeus, and indicates the authority who first named the species). Linnaeus was familiar with European hemp, which was widely cultivated at the time. In 1785, noted evolutionary biologist [[Jean-Baptiste de Lamarck]] published a description of a second species of ''Cannabis'', which he named ''Cannabis indica'' Lam.<ref name="lamarck1785">de Lamarck, J.B. 1785. ''Encyclopédie Méthodique de Botanique'', vol. 1, pt. 2. Paris, France, pp. 694-695</ref> Lamarck based his description of the newly named species on plant specimens collected in India. He described ''C. indica'' as having poorer fiber quality than ''C. sativa'', but greater utility as an [[Psychoactive drug|inebriant]]. Additional ''Cannabis'' species were proposed in the 19th century, including strains from China and Vietnam (Indo-China) assigned the names ''Cannabis chinensis'' Delile, and ''Cannabis gigantea'' Delile ex Vilmorin.<ref name="small1976a">Small, E. and A. Cronquist. 1976. A practical and natural taxonomy for ''Cannabis''. ''Taxon'' '''25'''(4): 405–435.</ref> However, many taxonomists found these putative species difficult to distinguish. In the early 20th century, the single-species concept was still widely accepted, except in the Soviet Union where ''Cannabis'' continued to be the subject of active taxonomic study. The name ''Cannabis indica'' was listed in various [[Pharmacopoeia]]s, and was widely used to designate ''Cannabis'' suitable for the manufacture of medicinal preparations.<ref name=”winek1977”>Winek, C. L. 1977. Some historical aspects of marijuana. ''Clinical Toxicology'' '''10'''(2): 243-253.</ref>
=== 20th Century ===
In 1924, Russian botanist D.E. Janichevsky concluded that [[ruderal]] ''Cannabis'' in central Russia is either a variety of ''C. sativa'' or a separate species, and proposed ''C. sativa'' L. var. ''ruderalis'' Janisch. and ''Cannabis ruderalis'' Janisch. as alternative names.<ref name=small1975b/> In 1929, renown plant explorer [[Nikolai Vavilov]] assigned wild or feral populations of ''Cannabis'' in Afghanistan to ''C. indica'' Lam. var. ''kafiristanica'' Vav., and ruderal populations in Europe to ''C. sativa'' L. var. ''spontanea'' Vav.<ref name="hillig2004a">Hillig, Karl W. and Paul G. Mahlberg. 2004. [http://www.amjbot.org/cgi/content/abstract/91/6/966 A chemotaxonomic analysis of cannabinoid variation in ''Cannabis'' (Cannabaceae)]. ''American Journal of Botany'' '''91'''(6): 966-975. Retrieved on 22 Feb 2007</ref><ref name=small1976a/> In 1940, Russian botanists Serebriakova and Sizov proposed a complex classification in which they also recognized ''C. sativa'' and ''C. indica'' as separate species. Within ''C. sativa'' they recognized two subspecies: ''C. sativa'' L. subsp. ''culta'' Serebr. (consisting of cultivated plants), and ''C. sativa'' L. subsp. ''spontanea'' (Vav.) Serebr. (consisting of wild or feral plants). Serebriakova and Sizov split the two ''C. sativa'' subspecies into 13 varieties, including four distinct groups within subspecies ''culta''. However, they did not divide ''C. indica'' into subspecies or varieties.<ref name=small1975b/><ref name="serebriakova1940">Serebriakova T. Ya. and I. A. Sizov. 1940. Cannabinaceae Lindl. In: Vavilov N. I. (ed.), ''Kulturnaya Flora SSSR'', vol. 5, Moscow-Leningrad, USSR, pp. 1-53. [in Russian]</ref> This excessive splitting of ''C. sativa'' proved too unwieldy, and never gained many adherents.
[[Image:Cannabis ruderalis.jpg|right|thumb|Ruderal ''Cannabis''.]]
In the 1970s, the taxonomic classification of ''Cannabis'' took on added significance in North America. Laws prohibiting ''Cannabis'' in the United States and Canada specifically named products of ''C. sativa'' as prohibited materials. Enterprising attorneys for the defense in a few drug busts argued that the seized ''Cannabis'' material may not have been ''C. sativa'', and was therefore not prohibited by law. Attorneys on both sides recruited botanists to provide expert testimony. Among those testifying for the prosecution was Dr. Ernest Small, while [[Richard E. Schultes|Dr. Richard E. Schultes]] and others testified for the defense. The botanists engaged in heated debate (outside of court), and both camps impugned the other's integrity.<ref name=small1975a/><ref name=emboden1981a/> The defense attorneys were not often successful in winning their case, because the intent of the law was clear.<ref name=”watts2006”>Watts, G. 2006. [http://www.bmj.com/cgi/reprint/332/7534/175.pdf ''Cannabis'' confusions]. BMJ 332: 175-176. Retrieved on 23 Feb 2007</ref>
In 1976, Canadian botanist Ernest Small<ref name=”smallbiography”>[http://pubs.nrc-cnrc.gc.ca/cgi-bin/rp/rp2_gene_e?mlist-authors-small_e.html Ernest Small (biography)]. National Research Council Canada. Retrieved on 23 Feb 2007</ref> and American taxonomist [[Arthur Cronquist]] published a taxonomic revision that recognizes a single species of ''Cannabis'' with two subspecies: ''C. sativa'' L. subsp. ''sativa'', and ''C. sativa'' L. subsp. ''indica'' (Lam.) Small & Cronq.<ref name=small1976a/> The authors hypothesized that the two subspecies diverged primarily as a result of human selection; ''C. sativa'' subsp. ''sativa'' was presumably [[Artificial selection|selected]] for traits that enhance fiber or seed production, whereas ''C. sativa'' subsp. ''indica'' was primarily selected for drug production. Within these two subspecies, Small and Cronquist described ''C. sativa'' L. subsp. ''sativa'' var. ''spontanea'' Vav. as a wild or escaped variety of low-intoxicant ''Cannabis'', and ''C. sativa'' subsp. ''indica'' var. ''kafiristanica'' (Vav.) Small & Cronq. as a wild or escaped variety of the high-intoxicant type. This classification was based on several factors including interfertility, chromosome uniformity, chemotype, and numerical analysis of [[phenotypic]] characters.<ref name=small1973a/><ref name=small1976a/><ref name="small1976b">Small, E., P. Y. Jui, and L. P. Lefkovitch. 1976. A numerical taxonomic analysis of ''Cannabis'' with special reference to species delimitation. ''Systematic Botany'' '''1'''(1): 67-84.</ref>
Professors William Emboden, Loran Anderson, and Harvard botanist [[Richard E. Schultes]] and coworkers also conducted taxonomic studies of ''Cannabis'' in the 1970s, and concluded that stable [[morphology (biology)|morphological]] differences exist that support recognition of at least three species, ''C. sativa'', ''C. indica'', and ''C. ruderalis.''<ref name=”schultes1974a”>Schultes, R. E., W. M. Klein, T. Plowman, and T. E. Lockwood. 1974. ''Cannabis'': an example of taxonomic neglect. ''Harvard University Botanical Museum Leaflets'' '''23''': 337–367.</ref><ref name=”anderson1974a”>[http://www.bio.fsu.edu/faculty-anderson.php Anderson, L. C.] 1974. A study of systematic wood anatomy in ''Cannabis''. ''Harvard University Botanical Museum Leaflets'' '''24''': 29–36. Retrieved on 23 Feb 2007</ref><ref name=”anderson1980a”>[http://www.bio.fsu.edu/faculty-anderson.php Anderson, L. C.] 1980. Leaf variation among ''Cannabis'' species from a controlled garden. ''Harvard University Botanical Museum Leaflets'' '''28''': 61–69. Retrieved on 23 Feb 2007</ref><ref name=emboden1974a>Emboden, W. A. 1974. ''Cannabis'' – a polytypic genus. ''Economic Botany'' '''28''': 304-310.</ref> For Schultes, this was a reversal of his previous interpretation that ''Cannabis'' is monotypic, with only a single species.<ref name="schultes1970a">Schultes, R. E. 1970. Random thoughts and queries on the botany of ''Cannabis''. In: Joyce, C. R. B. and Curry, S. H. (eds), ''The Botany and Chemistry of Cannabis''. J. & A. Churchill, London, pp. 11-38.</ref> According to Schultes' and Anderson's descriptions, ''C. sativa'' is tall and laxly branched with relatively narrow leaflets, ''C. indica'' is shorter, conical in shape, and has relatively wide leaflets, and ''C. ruderalis'' is short, branchless, and grows wild in [[central Asia]]. This taxonomic interpretation was embraced by ''Cannabis'' aficionados who commonly distinguish narrow-leafed "sativa" drug [[cannabis strains|strains]] from wide-leafed "indica" drug strains.<ref name="clarke2005a">[http://www.norml.org.nz/modules.php?name=News&file=print&sid=588 Interview with Robert Connell Clarke]. 1 Jan 2005. NORML, New Zealand. Retrieved on 19 Feb 2007</ref>
=== Ongoing research ===
[[Molecular biology|Molecular analytical techniques]] developed in the late twentieth century are being applied to questions of taxonomic classification. This has resulted in many reclassifications based on [[History of plant systematics#Evolutionary systematics|evolutionary systematics]]. Several studies of Random Amplified Polymorphic DNA ([[RAPD]]) and other types of genetic markers have been conducted on drug and fiber strains of ''Cannabis'', primarily for plant breeding and forensic purposes.<ref name=”faeti1996a”>Faeti, V., G. Mandolino, and P. Ranalli. 1996. Genetic diversity of ''Cannabis sativa'' germplasm based on RAPD markers. ''Plant Breeding'' '''115''': 367–370.</ref><ref name=”forapani2001a”>Forapani, S., A. Carboni, C. Paoletti, V. M. Christiana Moliterni, P. Ranalli, and G. Mandolino. 2001. [http://crop.scijournals.org/cgi/content/abstract/41/6/1682 Comparison of hemp (''Cannabis sativa'' L.) varieties using Random Amplified Polymorphic DNA markers]. ''Crop Science'' '''41''': 1682-1689. Retrieved on 23 Feb 2007</ref><ref name="mandolino2002a">Mandolino, G. and Ranalli, P. 2002. [https://www.haworthpress.com/store/ArticleAbstract.asp?sid=WHMFTL5P4HRL8KGL589LPHULAS5X554F&ID=8157 The applications of molecular markers in genetics and breeding of hemp]. ''Journal of Industrial Hemp'' '''7'''(1): 7-23. Retrieved on 23 Feb 2007</ref><ref name=”gilmore2003a”>Gilmore S., R. Peakall, and J. Roberts. 2003. [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T6W-478RNWR-7&_user=10&_coverDate=01%2F09%2F2003&_alid=541458074&_rdoc=2&_fmt=summary&_orig=search&_cdi=5041&_sort=d&_docanchor=&view=c&_ct=2&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=196333f36d13d0b0bacdfa4dbbfd5abe Short tandem repeats (STR) DNA markers are hypervariable and informative in ''Cannabis sativa'': implications for forensic investigations]. ''Forensic Science International'' '''131'''(1): 65-74. Retrieved on 25 Feb 2007</ref><ref name=”kojoka2002a”>Kojoka M., O. Iida, Y. Makino, S. Sekita, and M. Satake. 2002. DNA fingerprinting of ''Cannabis sativa'' using inter-simple sequence repeat (ISSR) amplification. ''Planta Medica'' '''68'''(1): 60-63.</ref> Dutch ''Cannabis'' researcher E.P.M. de Meijer and coworkers described some of their RAPD studies as showing an "extremely high" degree of genetic polymorphism between and within populations, suggesting a high degree of potential variation for selection, even in heavily selected hemp cultivars.<ref name="meijer2003a">Etienne P. M. de Meijer, M. Bagatta, A. Carboni, P. Crucitti, V. M. Cristiana Moliterni, P. Ranalli, and G. Mandolino. 2003. [http://www.genetics.org/cgi/content/abstract/163/1/335 The Inheritance of Chemical Phenotype in ''Cannabis sativa'' L.] ''Genetics'' '''163'''(1): 335-346. Retrieved on 23 Feb 2007</ref> They also commented that these analyses confirm the continuity of the ''Cannabis'' gene pool throughout the studied accessions, and provide further confirmation that the genus comprises a single species.
Karl W. Hillig, a [[graduate]] student in the laboratory of long-time ''Cannabis'' researcher Paul G. Mahlberg<ref name=”mahlbergNAIHC”>[http://www.naihc.org/MahlbergArticles.html Dr. Paul G. Mahlberg's ''Cannabis'' Research]. North American Industrial Hemp Council. Retrieved on 23 Feb 2007</ref> at [[Indiana University (Bloomington)|Indiana University]], conducted a systematic investigation of genetic, morphological, and [[chemotaxonomic]] variation among 157 ''Cannabis'' accessions of known geographic origin, including fiber, drug, and feral populations. In 2004, Hillig and Mahlberg published a chemotaxomic analysis of cannabinoid variation in their ''Cannabis'' [[germplasm]] collection. They used [[gas chromatography]] to determine cannabinoid content and to infer [[allele]] frequencies of the [[gene]] that controls CBD and THC production, within the studied populations.<ref name=hillig2004a/> Hillig and Mahlberg concluded that the patterns of cannabinoid variation support recognition of ''C. sativa'' and ''C. indica'' as separate species, but not ''C. ruderalis.'' The authors assigned fiber/seed landraces and feral populations from Europe, central Asia, and Asia Minor to ''C. sativa''. Narrow-leaflet and wide-leaflet drug accessions, southern and eastern Asian hemp accessions, and feral Himalayan populations were assigned to ''C. indica.'' In 2005, Hillig published a genetic analysis of the same set of accessions (this paper was submitted ahead of his 2004 manuscript with Mahlberg, but was delayed in publication), and proposed a three-species classification, recognizing ''C. sativa'', ''C. indica'', and (tentatively) ''C. ruderalis''.<ref name=”hillig2005a”>Hillig, Karl W. 2005. [http://www.ingentaconnect.com/content/klu/gres/2005/00000052/00000002/00004452 Genetic evidence for speciation in ''Cannabis'' (Cannabaceae)]. ''Genetic Resources and Crop Evolution'' '''52'''(2): 161-180. Retrieved on 23 Feb 2007</ref> In his doctoral [[dissertation]] published the same year, Hillig stated that [[principal components analysis]] of [[phenotypic]] (morphological) traits failed to differentiate the putative species, but that [[canonical analysis|canonical variates analysis]] resulted in a high degree of discrimination of the putative species and infraspecific taxa.<ref name=”hillig2005b”>Hillig, Karl William. 2005. A systematic investigation of ''Cannabis''. Doctoral Dissertation. Department of Biology, Indiana University. Bloomington, Indiana. Published by [http://wwwlib.umi.com/dxweb/gateway UMI]. Retrieved on 23 Feb 2007</ref> Another paper published by Hillig on chemotaxonomic variation in the [[terpenoid]] content of the essential oil of ''Cannabis'' revealed that several wide-leaflet drug strains in their collection had relatively high levels of certain [[sesquiterpene]] alcohols, including guaiol and isomers of eudesmol, that set them apart from the other putative taxa.<ref name="hillig2004b">Hillig, Karl W. 2004. [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T4R-4CPD4SG-1&_user=10&_coverDate=10%2F31%2F2004&_rdoc=1&_fmt=&_orig=search&_sort=d&view=c&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=9e491613fa59a0a2cb5b5a3f83cd3118 A chemotaxonomic analysis of terpenoid variation in ''Cannabis'']. ''Biochemical Systematics and Ecology'' '''32''': 875-891. Retrieved on 23 Feb 2007</ref> Hillig concluded that the patterns of genetic, morphological, and chemotaxonomic variation support recognition of ''C. sativa'' and ''C. indica'' as separate species. He also concluded there is little support to treat ''C. ruderalis'' as a separate species from ''C. sativa'' at this time, but more research on wild and weedy populations is needed because they were underrepresented in their collection.
As of 2007, most taxonomy web sites continue to list ''Cannabis'' as a single species.<ref name="GRIN">USDA, ARS, National Genetic Resources Program. [http://www.ars-grin.gov/cgi-bin/npgs/html/splist.pl?2034 Germplasm Resources Information Network - (GRIN)], National Germplasm Resources Laboratory, Beltsville, Maryland. Retrieved on 23 Feb 2007</ref><ref name="APNI">Barlow, Snow. 2006. [http://www.plantnames.unimelb.edu.au/Sorting/Cannabis.html Sorting ''Cannabis'' names]. Multilingual Multiscript Plant Name Database. The University of Melbourne. Retrieved on 23 Feb 2007</ref><ref name="ITIS">[http://www.itis.gov/servlet/SingleRpt/SingleRpt?search_topic=TSN&search_value=19109 Integrated Taxonomic Information System (ITIS)]. Retrieved on 23 Feb 2007</ref><ref name="taxonomicon">[http://www.taxonomy.nl/Taxonomicon/TaxonTree.aspx?id=6455 The Taxonomicon]. Universal Taxonomic Services. Retrieved on 23 Feb 2007</ref>
===U.S. founding fathers who cultivated cannabis===
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|<center>[[Image:George Washington dollar.jpg|175px]]</center><center>''[[George Washington]]''</center> || style="width:500px"| [[Major General]] [[George Washington]], [[U.S. Revolutionary War]] hero and first president of the United States, shown here on a [[U.S. dollar]] treasury note, cultivated hemp as a crop on his farm.<ref name="altahemp">
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|<center>[[Image:Tj3.gif|175px]]</center><center>''[[Thomas Jefferson]]''</center> || style="width:500px"| [[Thomas Jefferson]], the principal author of the American [[Declaration of Independence]], which he drafted on hemp paper, was the third president of the United States. He cultivated hemp.<ref name="altahemp"/>
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|<center>[[Image:Benjamin-Franklin-U.S.-$100-bill.jpg|175px]]</center><center>''[[Benjamin Franklin]]''</center> || style="width:500px"| [[Benjamin Franklin]], shown here on a [[U.S. $100 bill]], started the first American [[paper mill]], which made paper exclusively from hemp.<ref>
{{cite web
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|title=American Hemp History
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=== Popular usage ===
The scientific debate regarding taxonomy has had little effect on the terminology in widespread use among cultivators and users of drug-type ''Cannabis''. ''Cannabis'' aficionados recognize three distinct types based on such factors as morphology, native range, aroma, and subjective psychoactive characteristics. "Sativa" is the term used to describe the most widespread variety, which is usually tall, laxly branched, and found in warm lowland regions. "Indica" is used to designate shorter, bushier plants adapted to cooler climates and highland environments. "Ruderalis" is the term used to describe the short plants that grow wild in Europe and central Asia.
Breeders, seed companies, and cultivators of drug type ''Cannabis'' often describe the ancestry or gross [[phenotype|phenotypic]] characteristics of [[cultivar]]s by categorizing them as "pure indica," "mostly indica," "indica/sativa," "mostly sativa", or "pure sativa."
In September 2005, [[New Scientist]] reported that researchers at the Canberra Institute of Technology had identified a new type of ''Cannabis'' based on analysis of [[mitochondria]]l and [[chloroplast]] DNA.<ref name=”newscientist”>2005. [http://www.newscientist.com/article.ns?id=mg18725175.200 Rasta lends its name to a third type of ''Cannabis'']. ''New Scientist'' '''2517''': 12. Retrieved on 24 Feb 2007</ref> The New Scientist story, which was picked up by many news agencies and web sites, indicated that the research was to be published in the journal ''Forensic Science International''. As of 25 Feb 2007 the article is listed as "in press," and there is no mention in the abstract of "Rasta."<ref name=gilmore2007a>Gilmore, S., R. Peakall, and J. Robertson. 2007. [http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6T6W-4N1SJSG-1&_user=10&_coverDate=02%2F12%2F2007&_alid=541458074&_rdoc=1&_fmt=summary&_orig=search&_cdi=5041&_sort=d&_docanchor=&view=c&_ct=2&_acct=C000050221&_version=1&_urlVersion=0&_userid=10&md5=18b36b5a075a1cf95491de46a56b6c7f Organelle DNA haplotypes reflect crop-use characteristics and geographic origins of ''Cannabis sativa'']. ''Forensic Science International''. In Press. Retrieved on 25 Feb 2007</ref>
=== Wild cannabis ===
Wild ''C. sativa'' subsp. ''indica'' is mainly confined to [[hashish]] producing areas such as [[Afghanistan]], and parts of [[Morocco]]. In the U.S. wild cannabis can grow wild in mid-west areas such as Kansas and Nebraska. This type is not valued for recreational use and is viewed as a weed by farmers. Wild ''C. sativa'' subsp. ''sativa'' shows great local variation; for example, in warm places, it can reach heights up to 20 feet (6 m) tall, but in colder climates it can be as short as 1 foot (30 cm) in height. Almost every single flower branch bears a seed. The wild ''C. sativa'' subsp. ''sativa'' has long, thin and airy buds and a Christmas tree shape structure. Wild ''C. sativa'' subsp. ''indica'' remains compact and bushy with thick buds for the most part, and is sometimes used by the locals for hashish production. Generally, there are far fewer seeds in wild ''C. sativa'' subsp. ''indica''.
In many areas, wild or naturalized populations of ''Cannabis'' are considered [[invasive species]], and are often targeted by government-sponsored eradication programmes.
== Reproduction ==
=== Breeding systems ===
[[Image:CannabisSeeds.jpg|right|thumb|Some ''Cannabis sativa'' seeds]]
[[Image:Cannabis female flowers close-up.jpg|thumb|Female Cannabis flowers.]]
[[Image:Cannabis male flowers.JPG|thumb|Male Cannabis flowers.]]
''Cannabis'' is predominantly [[dioecious]],<ref name=clarke1991a/><ref name="ainsworth2000">Ainsworth, C. 2000. [http://aob.oxfordjournals.org/cgi/reprint/86/2/211 Boys and girls come out to play: the molecular biology of dioecious plants]. ''Annals of Botany'' '''86'''(2): 211-221. Retrieved on 24 Feb 2007</ref> although many monoecious varieties have been described.<ref name="meijer1999a">de Meijer, E. P. M. 1999. ''Cannabis'' germplasm resources. In: Ranalli P. (ed.). ''Advances in Hemp Research'', Haworth Press, Binghamton, NY, pp. 131-151. ISBN 1-56022-872-5</ref> Subdioecy (the occurrence of monoecious individuals and dioecious individuals within the same population) is widespread.<ref name="mignoni1999">{{cite web|url=http://www.globalhemp.com/Archives/Government_Research/UN/03_odccp_bulletin.html|title=Cannabis as a licit crop: recent developments in Europe|accessDate=February, 2008}}</ref><ref name="schumann1999">Schumann, E., A. Peil, and W. E. Weber. 1999. [http://www.springerlink.com/content/j0581734t3222674/?p=17537b5e5396490d82c1dd09c0da993d&pi=9 Preliminary results of a German field trial with different hemp (''Cannabis sativa'' L.) accessions]. ''Genetic Resources and Crop Evolution'' '''46'''(4): 399-407. Retrieved on 24 Feb 2007</ref><ref name="ranalli2004a">Ranalli, P. 2004. Current status and future scenarios of hemp breeding. ''Euphytica'' '''140'''(1): 121-131.</ref> Many populations have been described as sexually labile.<ref name="hirata1924">Hirata, K. 1924. Sex reversal in hemp. ''Journal of the Society of Agriculture and Forestry'' '''16''': 145-168.</ref><ref name="schaffner1931">Schaffner, J. H. 1931. The fluctuation curve of sex reversal in staminate hemp plants induced by photoperiodicity. ''American Journal of Botany'' '''18'''(6): 424-430.</ref><ref name="mandolino2002a"/>
As a result of intensive selection in cultivation, ''Cannabis'' exhibits many sexual phenotypes that can be described in terms of the ratio of female to male flowers occurring in the individual, or typical in the cultivar.<ref name="truta2002a">Truta, E., E. Gille, E. Toth, and M. Maniu. 2002. [http://jag.igr.poznan.pl/2002-Volume-43/4/pdf/2002_Volume_43_4-451-462.pdf Biochemical differences in ''Cannabis sativa'' L. depending on sexual phenotype]. ''Journal of Applied Genetics'' '''43'''(4): 451-462. Retrieved on 24 Feb 2007</ref> Dioecious varieties are preferred for drug production, where the [[Cannabis (drug) cultivation#Sinsemilla|female plants]] are preferred. Dioecious varieties are also preferred for textile fiber production, whereas monoecious varieties are preferred for pulp and paper production. It has been suggested that the presence of monoecy can be used to differentiate between licit crops of monoecious hemp and illicit dioecious drug crops.<ref name="mignoni1999"/>
=== Mechanisms of sex determination ===
''Cannabis'' has been described as having one of the most complicated mechanisms of [[sex determination]] among the dioecious plants.<ref name="truta2002a"/> Many models have been proposed to explain sex determination in ''Cannabis''.
Based on studies of sex reversal in [[hemp]], it was first reported by K. Hirata in 1924 that an [[XY sex-determination system]] is present.<ref name="hirata1924"/> At the time, the XY system was the only known system of sex determination. The [[X0 sex-determination system|X:A system]] was first described in Drosophila spp in 1925.<ref name=”bridges1925”>Bridges, C. B. 1925. Sex in relation to chromosomes and genes. ''American Naturalist'' '''59''': 127-137.</ref> Soon thereafter, Schaffner disputed Hirata's interpretation,<ref name="schaffner1929">Schaffner, J. H. 1929. Heredity and sex. ''Ohio Journal of Science'' '''29'''(1): 289-300.</ref> and published results from his own studies of sex reversal in hemp, concluding that an X:A system was in use and that furthermore sex was strongly influenced by environmental conditions.<ref name="schaffner1931"/>
Since then, many different types of sex determination systems have been discovered, particularly in plants.<ref name="ainsworth2000"/> Dioecy is relatively uncommon in the plant kingdom, and a very low percentage of dioecious plant species have been determined to use the XY system. In most cases where the XY system is found it is believed to have evolved recently and independently.<ref name=”negrutiu2001”> Negrutiu, I., B. Vyskot, N. Barbacar, S. Georgiev, and F. Moneger. 2001. [http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1540173 Dioecious plants; a key to the early events of sex chromosome evolution]. ''Plant Physiology'' '''127'''(4): 418-424.</ref>
Since the 1920s, a number of sex determination models have been proposed for ''Cannabis''. Ainsworth describes sex determination in the genus as using "an X/autosome dosage type".<ref name="ainsworth2000"/>
[[Image:Cannabis indica Selkem.jpg|left|thumb|Dense raceme of carpellate flowers typical of drug-type varieties of ''Cannabis'']]
The question of whether heteromorphic sex chromosomes are indeed present is most conveniently answered if such chromosomes were clearly visible in a [[karyotype]]. ''Cannabis'' was one of the first plant species to be karyotyped; however, this was in a period when karyotype preparation was primitive by modern standards (see [[Cytogenetics#History|History of Cytogenetics]]). Heteromorphic sex chromosomes were reported to occur in staminate individuals of dioecious "Kentucky" hemp, but were not found in pistillate individuals of the same variety. Dioecious "Kentucky" hemp was assumed to use an XY mechanism. Heterosomes were not observed in analyzed individuals of monoecious "Kentucky" hemp, nor in an unidentified German cultivar. These varieties were assumed to have sex chromosome composition XX.<ref name="menzel1964">Menzel, Margaret Y. 1964. Meiotic chromosomes of monoecious Kentucky hemp (''Cannabis sativa''). ''Bulletin of the Torrey Botanical Club'' '''91'''(3): 193-205.</ref> According to other researchers, no modern karyotype of ''Cannabis'' had been published as of 1996.<ref name=”hong1996a”>Shao Hong and Robert C. Clarke. 1996. [http://www.hempfood.com/IHA/iha03207.html Taxonomic studies of Cannabis in China]. ''Journal of the International Hemp Association'' '''3'''(2): 55-60. Retrieved on 25 Feb 2007</ref> Proponents of the XY system state that Y chromosome is slightly larger than the X, but difficult to differentiate cytologically.<ref name="peil2003">Peil, A., H. Flachowsky, E. Schumann, and W. E. Weber. 2003. Sex-linked AFLP markers indicate a pseudoautosomal region in hemp (''Cannabis sativa'' L.). ''Theoretical and Applied Genetics'' '''107'''(1): 102-109.</ref>
More recently, Sakamoto and various co-authors<ref name=”sakamoto1995a”> Sakamoto, K., K. Shimomura, Y. Komeda, H. Kamada, and S. Satoh. 1995. [http://pcp.oxfordjournals.org/cgi/content/abstract/36/8/1549 A male-associated DNA sequence in a dioecious plant, ''Cannabis sativa'' L.] ''Plant & Cell Physiology'' '''36'''(8): 1549-1554. Retrieved on 25 Feb 2007</ref><ref name=”sakamoto2005a”> Sakamoto, K., T. Abe, T. Matsuyama, S. Yoshida, N. Ohmido, K. Fukui, and S. Satoh. 2005. [http://article.pubs.nrc-cnrc.gc.ca/ppv/RPViewDoc?_handler_=HandleInitialGet&journal=gen&volume=48&calyLang=eng&articleFile=g05-056.pdf RAPD markers encoding retrotransposable elements are linked to the male sex in ''Cannabis sativa'' L.] ''Genome'' '''48'''(5): 931-936. Retrieved on 25 Feb 2007</ref> have used [[RAPD]] to isolate several [[genetic marker]] sequences that they name Male-Associated DNA in Cannabis (MADC), and which they interpret as indirect evidence of a male chromosome. Several other research groups have reported identification of male-associated markers using RAPD and [[Amplified fragment length polymorphism|AFLP]].<ref name="torjek2002">Törjék, O., N. Bucherna, E. Kiss, H. Homoki, Z. Finta-Korpelová, I. Bócsa, I. Nagy, and L. E. Heszky. 2002. Novel male specific molecular markers (MADC5, MADC6) for sex identification in hemp. ''Euphytica'' '''127''': 209-218.</ref><ref name="mandolino2002a">Mandolino, Giuseppe and Paolo Ranalli. 2002. [https://www.haworthpress.com/store/ArticleAbstract.asp?sid=WHMFTL5P4HRL8KGL589LPHULAS5X554F&ID=8157 The applications of molecular markers in genetics and breeding of hemp]. ''Journal of Industrial Hemp'' '''7'''(1): 7-23. Retrieved on 23 Feb 2007</ref><ref name="meijer2003a">Meijer, Etienne P. M. de, M. Bagatta, A. Carboni, P. Crucitti, V. M. Cristiana Moliterni, P. Ranalli, and G. Mandolino. 2003. [http://www.genetics.org/cgi/content/abstract/163/1/335 The Inheritance of Chemical Phenotype in ''Cannabis sativa'' L.] ''Genetics'' '''163'''(1): 335-346. Retrieved on 23 Feb 2007</ref> Ainsworth commented on these findings, stating,<blockquote>It is not surprising that male-associated markers are relatively abundant. In dioecious plants where sex chromosomes have not been identified, markers for maleness indicate either the presence of sex chromosomes which have not been distinguished by cytological methods or that the marker is tightly linked to a gene involved in sex determination.<ref name="ainsworth2000" /></blockquote>
Environmental sex determination is known to occur in a variety of species.<ref name=”tanurdzic2004”>Tanurdzic, M. and J. A. Banks. 2004. Sex-determining mechanisms in land plants. ''Plant Cell'' '''16''' (suppl.): S61-71.</ref> Many researchers have suggested that sex in ''Cannabis'' is determined or strongly influenced by environmental factors.<ref name=schaffner1931/> Ainsworth reviews that treatment with [[auxin]] and [[ethylene]] have feminizing effects, and that treatment with [[cytokinins]] and [[gibberellins]] have masculinizing effects.<ref name=ainsworth2000/> It has been reported that sex can be reversed in ''Cannabis'' using chemical treatment.<ref name=”mohanram1982”>Mohan Ram, H. Y., and R. Sett. 1982. Induction of fertile male flowers in genetically female ''Cannabis sativa'' plants by silver nitrate and silver thiosulfate anionic complex. ''Theoretical and Applied Genetics'' '''62''': 369-375.</ref>
A [[PCR]]-based method for the detection of female-associated [[Polymorphism (biology)|DNA polymorphisms]] by [[genotyping]] has been developed.<ref name=PCR>Journal of Industrial Hemp 2003 Vol 8 issue 1 page 5-9, Female-Associated DNA Polymorphisms of Hemp (''Cannabis sativa'' L.), Hong Shao, Shu-Juan Song, Robert C. Clarke </ref>
==Various strains of cannabis==
Although there are hundreds of strains of cannabis in existence, there are also many rumors and urban legends. Many alleged strains, such as [[Purple Haze]], are very predominant in pop-culture (see right), but the actual existence of many of these strains is uncertain and the slang terms used to refer to these strains do not appear to be used by botanists. Some strains, such as [[G-13]], are acknowledged to be [[urban legend]]s.<ref>Doorenbos, Norman J., Patricia S. Fetterman, Maynard W. Quimby, and Carlton Turner. 1971. Cultivation, extraction, and analysis of Cannabis sativa L. Annals New York Academy of Sciences 191: 3-14.</ref>
Strains of cannabis:
* [[Acapulco gold]]
* [[BC Bud]]
* Cinderella 99
* Chocolate Thai
* [[Panama Red]]
* [[G-13]]
* [[Kush (cannabis)|Kush]]
* [[Northern Lights (strain)|Northern Lights]]
* [[Purple Haze (marijuana)|Purple Haze]]
* [[Quebec Gold (marijuana)|Quebec Gold]]
* [[White widow (cannabis)|White Widow]]
Some of the strains' names, such as ''Chocolate Thai'',<ref>{{cite journal | last=Hirsch | first=Robert | coauthors=''Edited by'' Judith Pynchon | title=Clinicians' self-assessment questions and answers in substance abuse treatment | publisher=Journal of Substance Abuse | volume=14 | issue=1 | pages=95–98 | year=1997 | doi=10.1016/S0740-5472(97)00050-0 | journal = Journal of Substance Abuse Treatment}}</ref> popular in the early 1990s due to its supposed high potency,<ref>[http://www.cannabisculture.com/articles/4280.html "Strains of Yesteryear" by DJ Short]</ref> entered the mass culture. For example, ''Chocolate Thai'' was adopted as a [[stage name]] of a jazz performer, whose album ''The Real McCoy'' was released in 2006.<ref>[http://www.answers.com/topic/the-real-mccoy-2006-album-by-chocolate-thai?cat=entertainment Answers.com album list]</ref> It should be noted, however, that because there is no manufacturing or state control over the process of production of cannabis, many "strains" may in fact be just marketing [[brands]] adopted by [[drug dealer]]s to increase sales.
== Aspects of ''Cannabis'' production and use ==
[[Image:Greendays01.jpg|190px|right|thumb|''Cannabis'' field seized by authorities]]
*[[Medical Cannabis]] discusses its use as a medication.
*[[Cannabis (drug)]] discusses its use as a recreational [[drug]].
*[[Spiritual use of cannabis]] discusses sacramental and religious use.
*[[Hemp]] discusses its uses as a source of [[house|housing]], [[Vegetable oil|oil]], [[food]], [[Fiber crop|fibers]], and industrial materials.
*[[Cannabis (drug) cultivation]] discusses aspects of cultivation for medicinal and recreational drug purposes
*[[Legality of cannabis]] focuses on the law and enforcement aspects of growing, transporting, selling and using cannabis as a drug.
**[[Cannabis rescheduling in the United States]]
**[[Drug policy of the Netherlands]]
*[[Health issues and the effects of cannabis]] discusses the [[pharmacology]], physical, and mental effects of ''Cannabis'' when used as drug.
==Gallery of images==
<gallery>
Image:Cannabis_sativa1.JPG|Cannabis plants
Image:Cannabis_sativa2.JPG|Cannabis plants
Image:Cannabis_sativa3.JPG|Cannabis plants
Image:Cannabis_sativa4.JPG|Cannabis plants
</gallery>
== References ==
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== See also==
*[[Medical Cannabis]]
*[[Cannabis (drug)]]
*[[Legality of cannabis by country]]
{{Cannabis resources}}
{{Ancient anaesthesia-footer}}
{{Herbal Sedatives}}
{{Herbs & spices}}
== Further reading ==
* ''Cannabis: A History'' (2005) Martin Booth ISBN 0-312-32220-8
* [http://www.unodc.org/pdf/WDR_2006/wdr2006_chap2_why.pdf ''UNODC: World Drug Report 2006, Chapter 2: Cannabis: Why We Should Care'' (2006)]
*[http://www.emcdda.europa.eu/?nnodeid=25484 EMCDDA drugs profile: Cannabis (2007)]
== External links ==
{{Portal}}
{{wiktionary}}
{{Wikispecies|Cannabis}}
{{commons|Cannabis sativa}}
{{wikiquote|Cannabis}}
* [http://www.ipni.org/ipni/advPlantNameSearch.do?find_family=&find_genus=Cannabis&find_species=&find_infrafamily=&find_infragenus=&find_infraspecies=&find_authorAbbrev=&find_includePublicationAuthors=off&find_includeBasionymAuthors=off&find_publicationTitle=&find_isAPNIRecord=on&find_isAPNIRecord=false&find_isGCIRecord=on&find_isGCIRecord=false&find_isIKRecord=on&find_isIKRecord=false&find_rankToReturn=all&output_format=normal&find_sortByFamily=on&find_sortByFamily=off&query_type=by_query&back_page=plantsearch International Plant Names Index (IPNI)]
* [http://www.endocannabinoid.net/ The Endocannabinoid System Network (ECSN)] - Contains medical information to the Endocannabinoid System
*[http://www.erowid.org/plants/cannabis/ Erowid: Cannabis (Marijuana) Vault].
[[Category:Cannabis|*]]
[[Category:Herbs]]
[[Category:Fiber plants]]
[[Category:Greek loanwords]]
[[Category:Underutilized crops]]
[[Category:Medicinal plants]]
[[Category:Psychedelics, dissociatives and deliriants]]
[[ar:قنب هندي]]
[[zh-min-nan:Toā-moâ]]
[[bg:Коноп]]
[[ca:Cànnabis]]
[[da:Cannabis]]
[[de:Hanf]]
[[et:Kanep]]
[[el:Κάνναβις]]
[[es:Cannabis sativa]]
[[eo:Kanabo]]
[[fa:شاهدانه]]
[[fr:Cannabis]]
[[hr:Konoplja]]
[[io:Kanabo]]
[[ilo:Cannabis]]
[[id:Cannabis]]
[[is:Kannabis]]
[[it:Cannabis]]
[[he:קנאביס]]
[[la:Cannabis]]
[[lt:Kanapė]]
[[hu:Kender]]
[[nl:Hennep]]
[[ja:アサ]]
[[no:Hamp]]
[[pt:Cannabis]]
[[qu:Kañamu]]
[[ru:Конопля]]
[[simple:Cannabis]]
[[sr:Конопља]]
[[fi:Kannabis]]
[[sv:Cannabis]]
[[vi:Cần sa]]
[[tr:Kenevir]]
[[uk:Коноплі (рослина)]]
[[zh:麻]]