Cultivated Tobacco

Nicotiana tabacum, tobacco, is a stout herbaceous plant in the Solanaceae (nightshade family) that originated in the tropical Americas (South America, Mexico, and the West Indies) and now cultivated worldwide as the primary commercial source of tobacco, which is smoked or chewed as a drug for its mild stimulant effects. The World Health Organization (WHO) estimates that around 1 billion people worldwide smoke tobacco—around 14% of the global population—making tobacco a major cash crop in many places. Tobacco, which is usually annual but in some varieties perennial, is a thick-stemmed viscid (gummy) plant that can grow 1 to 3 m (3 to 10 ft) tall, usually 1 to 2 m. The ovate to lanceolate leaves are alternate, spiraling around the stem, and often large—in many varieties, 0.6 to 1.0 m (2 to 3 ft) long and half as wide, although in some Near Eastern commercial varieties, they may only be around 8 cm (3 in) long. The tubular flowers, which range in color from white or cream to pink to carmine red, grow in a large, branching terminal clusters, with individual flowers 3.5 to 5 cm (1.25 to 2 in) long. The flowers may be attractive and aromatic—many related species of Nicotiana are grown as ornamentals—but in commercial cultivation, the inflorescence is generally cut off before fully developed to encourage greater leaf growth. Fruits are oval to elliptical capsules that contain several to numerous small brown seeds (0.5 mm, or less than 1/32nd in, in diameter). Tobacco use was observed by Christopher Columbus, who saw natives of Cuba inhaling the smoke through rolled leaves. It was widely used and cultivated for medicinal and ritual purposes (including peace pipe ceremonies) in many native cultures throughout North, Central, and South America. It was brought to Europe in the 1500s for medicinal purposes, although at first it was often considered a poison (it contains compounds that can be toxic in large amounts, and have been used as insecticides). However, tobacco use eventually expanded from occasional medicinal treatment to routine smoking and chewing, and its cultivation spread widely in the North American colonies, where it became an important cash crop, as well as to Europe, India, and China. Discovery of adverse health effects from smoking and the addictive effects of nicotine (its primary active component), as well as to the role of the tobacco industry in suppressing information about negative effects, have led to public health campaigns against smoking and restrictions on tobacco use, which have resulted in a decline of tobacco use in the U.S. in recent decades. FAO estimates that total commercial production was 7.1 million metric tons worldwide in 2010, harvested from 4.0 million hectares, with a market value of over $7.2 billion U.S. dollars. China was the largest producer, responsible for nearly 75% of the global harvest, followed by Brazil and India (with 19% and 18%, respectively). The U.S. was a distant 4th, producing around 8% of the total. Within the U.S., production has been declining since 1975 due to health concerns, but tobacco is still an important crop in southeastern states, including North Carolina, Kentucky, Tennessee, South Carolina, Virginia, and Georgia, partly due to increased demand for exports. Nicotine is usually compared in its addictive effects to widely banned drug products derived from opium (Papaver somniferum) and cocaine (Erythroxylum coca and E. novogranatense), rather than to milder stimulants of caffeine and theobromine derived from plant species including tea (Camellia sinensis), coffee (Coffea arabica and other Coffea species), cocoa (Theobroma cacao), and kola (Cola species). (Bailey et al. 1976, Congressional Research Service 2003, Encyclopedia Britannica 1993, Flora of China 1994, Hedrick 1919, Magness et al. 1971.)