Cannabis sativa

Cannabis sativa is an annual herbaceous flowering plant. The species was first classified by Carl Linnaeus in 1753. The specific epithet sativa means 'cultivated'. Indigenous to Eastern Asia, the plant is now of cosmopolitan distribution due to widespread cultivation. It has been cultivated throughout recorded history and used as a source of industrial fiber, seed oil, food, and medicine. It is also used as a recreational drug and for religious and spiritual purposes.

Description

The flowers of Cannabis sativa plants are most often either male or female, but, only plants displaying female pistils can be or turn hermaphrodite. Males can never become hermaphrodites. It is a short-day flowering plant, with staminate (male) plants usually taller and less robust than pistillate (female or male) plants. The flowers of the female plant are arranged in racemes and can produce hundreds of seeds. Male plants shed their pollen and die several weeks prior to seed ripening on the female plants. Under typical conditions with a light period of 12 to 14 hours, both sexes are produced in equal numbers because of heritable X and Y chromosomes. Although genetic factors dispose a plant to become male or female, environmental factors including the diurnal light cycle can alter sexual expression. Naturally occurring monoecious plants, with both male and female parts, are either sterile or fertile; but artificially induced "hermaphrodites" can have fully functional reproductive organs. "Feminized" seed sold by many commercial seed suppliers are derived from artificially "hermaphroditic" females that lack the male gene, or by treating the plants with hormones or silver thiosulfate.

Cultivation

A Cannabis plant in the vegetative growth phase of its life requires more than 16–18 hours of light per day to stay vegetative. Flowering usually occurs when darkness equals at least 12 hours per day. The flowering cycle can last anywhere between seven and fifteen weeks, depending on the strain and environmental conditions. When the production of psychoactive cannabinoids is sought, female plants are grown separately from male plants to induce parthenocarpy in the female plant's fruits (popularly called "sin semilla" which is Spanish for "without seed" ) and increase the production of cannabinoid-rich resin.

In soil, the optimum pH for the plant is 6.3 to 6.8. In hydroponic growing, the nutrient solution is best at 5.2 to 5.8, making Cannabis well-suited to hydroponics because this pH range is hostile to most bacteria and fungi.

Tissue culture multiplication has become important in producing medically important clones, while seed production remains the generally preferred means of multiplication. Sativa plants have narrow leaves and grow best in warm environments. They do, however, take longer to flower than their Indica counterparts, and they grow taller than the Indica cannabis strains as well.

Uses

Cannabis sativa seeds are chiefly used to make hempseed oil which can be used for cooking, lamps, lacquers, or paints. They can also be used as caged-bird feed, as they provide a source of nutrients for most animals. The flowers and fruits (and to a lesser extent the leaves, stems, and seeds) contain psychoactive chemical compounds known as cannabinoids that are consumed for recreational, medicinal, and spiritual purposes. When so used, preparations of flowers and fruits (called marijuana) and leaves and preparations derived from resinous extract (e.g., hashish) are consumed by smoking, vaporising, and oral ingestion. Historically, tinctures, teas, and ointments have also been common preparations. In traditional medicine of India in particular cannabis sativa has been used as hallucinogenic, hypnotic, sedative, analgesic, and anti-inflammatory agent. Terpenes have gained public awareness through the growth and education of medical and recreational cannabis. Organizations and companies operating in cannabis markets have pushed education and marketing of terpenes in their products as a way to differentiate taste and effects of cannabis. The entourage effect, which describes the synergy of cannabinoids, terpenes, and other plant compounds, has also helped further awareness and demand for terpenes in cannabis products.
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