Tobacco
Family Solanaceae
Nicotiana tabacum, tobacco (N. tabacum 1), is a viscid annual herb, 1-3 m tall, with simple ovate-lanceolate leaves, 50-75 cm long (N. tabacum 2), covered with multicellular hairs. Leaves ripen from the base of the stem upwards, indicated by a change in colour from green to yellowish. The flowers are borne in terminal racemes ( N. tabacum 3, N. tabacum 9) with up to 150 flowers per inflorescence. Each flower with a funnel-shaped corolla, 3-5 cm long, usually pink and with 5 stamens and a superior ovary. The fruit is a capsule containing numerous small seeds. Tobacco is grown for the alkaloid nicotine, which is most abundant in the leaves. The content varies with the location. The glandular hairs contain ethereal oils and resins, which determine the aroma of the tobacco.
Distribution
Tobacco probably originated in the Argentinean Andes and was cultivated in pre-Columbian times in the West Indies, Central America and the northern parts of South America. The genus is called after Jean Nicot, the French ambassador in Portugal, who introduced seeds in Europe from Brazil around 1560. In 1565 seeds were taken from England to Florida. Thereafter tobacco spread rapidly and by the first decade of the 17th century, it was reported from Africa, India, Japan, the Middle East and the Philippines. Today it is one of the most widely distributed crops with many variations. The leaves (N. tabacum 4) after curing, are processed in cigarettes, cigars, pipe tobacco, chewing tobacco and snuffing tobacco.
Use
In Europe, tobacco was first grown as an ornamental and for medicinally use. At the end of the 16th century sailors returning from the New World introduced the habit of smoking pipe. Sir Walther Raleigh introduced the habit at the court of Elisabeth II and soon it spread to Africa and Asia. A puritan reaction followed, but persecution and taxation could not stop the habit. Smoking cigarettes became popular during World War I. The different aroma’s are the result of adding flavourings like glycerine, liquorice, sugar and tonka beans. In Indonesia cloves are added.
The lowest leaves ripen about 3 months after planting and are picked by hand (N. tabacum 8). Each week 2-4 leaves are picked from a plant. The leaves are carefully cured (N. tabacum 5) and dried (N. tabacum 6), (N. tabacum 7), during which process the colour of the leaves changes from green to yellow. Next the leaves are sorted and baled. Usually the tobacco is left in bales for 1-2 years to mature before it is processed. Yields vary from about 1000 kg per ha in Africa, to 2000 or even more in the US and Europe. The main producing countries are the US, China and India. The biggest importers are the UK and Germany.