tobacco
tobacco name for any plant of the genus Nicotiana of the Solanaceae family ( nightshade family) and for the product manufactured from the leaf and used in cigars and cigarettes , snuff , and pipe and chewing tobacco. Tobacco plants are also used in plant bioengineering, and some of the 60 species are grown as ornamentals. The chief commercial species, N. tabacum, is believed native to tropical America, like most nicotiana plants, but has been so long cultivated that it is no longer known in the wild. N. rustica, a mild-flavored, fast-burning species, was the tobacco originally raised in Virginia, but it is now grown chiefly in Turkey, India, and Russia. The alkaloid nicotine is the most characteristic constituent of tobacco and is responsible for its addictive nature. The possible harmful effects of the nicotine, tarry compounds, and carbon monoxide in tobacco smoke vary with the individual's tolerance (see smoking ).
Cultivation and Curing
The tobacco plant is a coarse, large-leaved perennial, usually cultivated as an annual, grown from seed in cold frames or hotbeds and then transplanted to the field. Tobacco requires a warm climate and rich, well-drained soil. The plant is susceptible to numerous bacterial, fungal, and viral diseases (e.g., the tobacco mosaic virus) and is attacked by several species of worms, beetles, and moths. The characteristics of many of the named grades depend upon the regional environmental conditions and cultivation techniques. Tobacco leaves are picked as they mature, or they are harvested together with the stalk.
Tobacco leaves are cured, fermented, and aged to develop aroma and reduce the harsh, rank odor and taste of fresh leaves. Fire-curing, dating from pre-Columbian times, is done by drying the leaves in smoke; in air-curing, the leaves are hung in well-ventilated structures; in flue-curing, used for over half the total crop, the leaves are dried by radiant heat from flues or pipes connected to a furnace. The cured tobacco is graded, bunched, and stacked in piles called bulks or in closed containers for active fermentation and aging. Most commercial tobaccos are blends of several types, and flavorings (e.g., maple and other sugars) are often added.
World Production
The United States produced nearly 1.7 billion pounds of tobacco in 1997 (about one tenth of world production), of which about 30% was exported; the United States imports some tobacco for special purposes, e.g., Asian cigarette leaf for blending, Puerto Rican tobacco for cigar filler, and cigar-wrapper leaf from Sumatra and Java. In the United States about two thirds of the crop is grown in North Carolina and Kentucky. China, India, Brazil, Turkey, Malawi, and Zimbabwe are the other chief producing countries, and Russia, Japan, and Germany are the major importers.
Early History
The use of tobacco originated among the indigenous inhabitants of the Western Hemisphere in pre-Columbian times. Tobacco was introduced into Spain and Portugal in the mid-16th cent., initially for its supposed virtues as a panacea. It spread to other European countries and then to Asia and Africa, where its use became general in the 17th cent. The first tobacco to reach England was probably a crop harvested in Virginia, where John Rolfe experimented with Spanish types of tobacco seed and introduced tobacco as a crop as early as 1612. By 1619 tobacco had become a leading export of Virginia, where it was later used as a basis of currency.
Classification
Tobacco is classified in the division Magnoliophyta , class Magnoliopsida, order Solanales, family Solanaceae.
Bibliography
See R. Jahn, ed., Tobacco Dictionary (1954); J. C. Robert, The Story of Tobacco in America (1967); E. R. Billings, Tobacco (1875, repr. 1973); I. Gately, Tobacco: The Story of How Tobacco Seduced the World (2002).
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