A preparation of the plant Cannabis sativa, widely used as a recreational drug for its euphoric, relaxing properties: its extracts are found as hashish and marijuana. The plant, also called ganja or hemp, is an annual growing to 2·5 m/8 ft; its leaves have 57 narrow, toothed, spreading, finger-like lobes; there are tiny green flowers in terminal clusters, with males and females on separate plants. It is native to Asia, but widely cultivated elsewhere. It is a source of rope fibre and birdseed, but is best known as a narcotic resin. Its active principle, the cannabinoid tetrahydrocannabinol, was first synthesized in 1967. Historically, cannabis has been extensively used in medicine, but since the 1930s its therapeutic use has been abandoned because of its abuse potential. However, cannabinoids appear to have therapeutic value in pain due to nerve damage, eg in muscular sclerosis and in suppressing severe vomiting that occurs during cancer chemotherapy. AIDS patients have campaigned (so far unsuccessfully) for cannabis to be prescribed because it also promotes appetite. Use of cannabis is illegal in all Western countries, but in landmark legislation (Sep 2003) The Netherlands became the first country in the world to permit the medical use of cannabis when prescribed by a doctor as a painkiller where conventional drugs had been ineffective. In 1991 a receptor for cannabis was discovered in the human brain, and since then several molecules have been identified in the brain which bind to them. These molecules are believed to be the brain's own cannabis. They probably act as neurotransmitters to modify mood, memory, and muscle function, and may also have other functions. (Family: Cannabidaceae.)
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Cannabis sativa L |
Cannabis is a genus of flowering plant that includes one or more species.
Species
Cannabis sativa L
Putative species or subspecies:
C. = C. Cronquist C. = C. = C. sativaDescription
Cannabis is a dioecious annual flowering herb. Cannabis is dioecious , which means that entire plants usually bear only male or only female flowers, with male flowers borne on loose panicles, and female flowers borne on racemes. Dense clusters of female flowers produced by drug varieties of Cannabis are commonly called "buds" although in this usage the term refers to clusters of mature flowers, rather than the undeveloped shoots that the word ordinarily describes.
All varieties of Cannabis are wind-pollinated and produce seeds that are called nuts or achenes. Most varieties of Cannabis are short day plants , with the exception of C. C.
Cannabis is used as a food plant by the larvae of some Lepidoptera species including Ghost Moth and The Nutmeg.
Taxonomy
The genus Cannabis was formerly placed with nettles in the family Urticaceae or with mulberries in the family Moraceae, but is now considered along with hops (Humulus sp.) to belong to the family Cannabaceae.
All strains of Cannabis can interbreed, and produce fertile offspring, which means that all known Cannabis plants satisfy one criterion for a single species type called Cannabis sativa L.. But whether the different strains of Cannabis actually do constitute a single species or multiple species has been a contentious issue for more than two centuries.
Early classifications
Cannabis was first classified by Carolus Linnaeus in 1753 as a genus comprising a single species, called Cannabis sativa, describing hemp, which was widely cultivated at the time. In 1785, famous French biologist Jean-Baptiste Lamarck described C. indica, a type of Cannabis from India having morphological distinctiveness from the C. Numerous additional species were proposed in the 19th century, but by the beginning of the 20th century, the single-species concept was widely accepted., except within the Soviet Union, where Cannabis continued to be the subject of active taxonomic study.
20th Century
In 1924, Janischevsky described the low-intoxicant type of wild (ruderal) Cannabis found in central Russia as either a species or a variety, proposing C. ruderalis or C. In 1929, Vavilov described wild populations of drug-type Cannabis as the variiety C. indica var kafiristanica, and recognized the wild populations previously described by Janischevsky as the variety C. In 1940, Serebriakova and Sizov proposed a classification of Cannabis recognizing C. sativa L and C. Within common hemp, they recognized cultivated and wild populatins as distinct subspecies, C. culta and C. They additionally recognized a total of 17 varieties within C. sativa, including 4 distinct groups within the cultivated subspecies, but did not describe variation within C.
In the late 1960's and 1970's, the question of scientific classification of Cannabis took on legal importance in North America. Several persons charged with violating these laws claimed that the material was in fact derived from C. indica or C.
In the early 1970's, botanists Richard E. Schultes and Loran Anderson conducted taxonomic studies of Cannabis, and concluded that sufficient evidence exists to support recognition of three species, C. sativa L, C. indica Lam., and C. According to their species 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. This concept was embraced by Cannabis aficionados who commonly distinguish narrow-leafleted "sativa" drug strains from wide-leafleted "indica" drug strains.
In 1976, Ernest Small and Arthur Cronquist proposed a classification comprising a single species Cannabis sativa L, with two subspecies: C. sativa and C. According to this concept, C. sativa was selected for traits that enhance fiber or seed production and has low levels of the psychoactive delta-9-tetrahydrocannabinol (THC), whereas C. Within these subspecies they described C. spontanea (Vav.) as a wild or escaped type of low-intoxicant Cannabis, and described C. Cooley Prize by the American Association of Plant Taxonomists for his work involving Cannabis.
Ongoing research
Molecular analytical techniques developed in the late twentieth century are being brought to bear on questions of scientific classification.
Several groups conducted genetic analyses of RAPD markers among drug and fiber cultivars. Long-time Cannabis researcher EPM de Meijer described these analyses as confirming the continuity of the gene pool throughout the studied accessions, and as further confirmation that the genus comprises a single species.
In 2004, Karl W. They concluded that observed chemotypes support recognition of C. sativa and C. indica as distinct species, but concluded that recognition of C. ruderalis was not supported but rather was consistent with classification of C. ruderalis as C. The authors categorized fiber/seed landraces and feral populations from Europe, central Asia, and Asia Minor in C. sativa., and categorized narrow-leaflet drug (NLD), wide-leaflet drug (WLD) cultivars, southern and eastern Asian hemp cultivars, and feral Himalayan populations as C. indica. In 2005, Hillig published another paper based on the same research, with additional statistical analyses, and this time proposed a 3-species classification, recognizing C. sativa, C. indica, and C. Hillig stated that the patterns of variation support a two-species concept, but not recognition of C. ruderalis as a separate species from C.
As of 2006, the single-species concept of Cannabis continues to be widely accepted.
Popular usage
Breeders, seed companies, and cultivators of drug type Cannabis often describe the ancestry or gross phenotypic characteristics of cultivars by categorizing them as pure indica, mostly indica, indica/sativa, mostly sativa, or pure sativa.
In September of 2005, New Scientist reported that researchers at the Canberra Insitute of Technology had identified a new subspecies of Cannabis, based on analysis of mitochondrial and chloroplast DNA.
Geographical distribution
Wild cannabis
Wild C. Wild C. The wild C. Wild C. Generally, there are far fewer seeds in wild C.
In many areas, wild or naturalized populations of Cannabis are considered invasive species, and are often targeted by government-sponsored eradication programs.
Reproduction
Breeding systems
Cannabis has been described as predominantly dioecious , although some monoecious varieties have also been described Subdioecy (the occurrence of monoecious individuals and dioecious individuals within the same population) is widespread.
As a result of intensive selection in cultivation, Cannabis exhibits many sexual phenotypes, which can be described in terms of the ratio of female to male flowers occurring in the individual or typical in the cultivar.
Mechanisms of sex determination
Cannabis has been described as having one of the most complicated mechanisms of sex determination among the dioecious plants.
Based on studies of sex reversal in hemp, it was first reported in 1924 by K.
Since then, many different types of sex determination system have been discovered, particularly in plants.
Since the 1920's, a number of sex determination models have been proposed for 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 History of Cytogenetics).
More recently, Sakamoto and various co-authors 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.
Environmental sex determination is known to occur in a variety of species. Health issues and the effects of cannabis discusses the pharmacology, physical, and mental effects of Cannabis when used as drug.
Etymology
The plant name cannabis is probably of Semitic origin, possibly Hebrew.
Hebrew קְנֵה בֹּשֶׂם qěnēh bośem > English
However, the earlier Sumerian language used the word "kanubi", which means 'cane of two (sexes?)'.
The Biblical Hebrew term qěnēh bośem, literally "reed of balm", probably refers to cannabis according to some etymologists , but is more commonly thought to be lemon grass, calamus , or even sweet cane, due to widespread translation issues. Notably, this anointing oil is a special herbal formula that functions as a kind of polish and fragrance for the Ark and Tabernacle, and the Bible forbids its manufacture and use to anoint people (Exodus 30:31-33) with the exception of the Aaronic priesthood (Exodus 30:30)
Elsewhere, the Hebrew Bible simply uses "reed" qānēh as the name of a plant in four places whose context seems to mean "reed of balm" as a fragrant resin, Isaiah 43:24, Jeremiah 6:20, Ezekiel 27:19 and Song of Songs 4:14.
This Biblical Hebrew term is often mistranslated as "calamus", also called "lemon grass" (Cymbopogon citratus) or "sweet flag" (Acorus calamus), following an ancient misunderstanding in the Greek Septuagint translation.
Unambiguous Hebrew or Aramaic references to cannabis are rare and obscure.
The Scythian term cannabis probably derives from a Semitic origin as well. Sara Benetowa of the Institute of Anthropological Sciences in Warsaw is quoted in the Book of Grass as saying:
The astonishing resemblance between the Semitic kanbos and the Scythian cannabis lead me to suppose that the Scythian word was of Semitic origin. The Semites could also have spread the word during their migrations through Asia Minor.
Likely, the name 'cannabis' was known from the Semitic merchants who sold this commodity throughout the ancient trade routes of Southeast Asia.
Comparing the English word hemp and the Greek word kannabis shows that the word came down from the presumed Proto-Indo-European language.
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