1) It is one of the very few crops entering world trade entirely on a leaf basis.

2) It is the most widely grown commercial non-food plant in the world.

3) It holds a high importance in financial and economic policies in many countries.

4) Consumption is by way of smoking, inhaling or chewing and is a habit forming narcotic, and although bans of it's use have been attempted, it's consumption marches steadily forward.

5) Originally having religious significance, subsequent claims of medicinal benefit have alternated with accusations of a positive danger to health.

Tobacco is grown with assistance of man with the leaf as the only valuable part of the plant. Tobacco growth is restricted, by environmental factors, to about the latitudes of 60 degrees north to 45 degrees south, with the majority of the tobacco entering the world trade produced in the latitudes between 45 degrees north and 30 degrees south. Limits to it's growth are figured by the number of frost free days. Almost all continents are capable of growing tobacco but the United States, China, India and Brazil are the leading countries to grow tobacco. (1)

History

Natural occurrence of Nicotiana is restricted to the American continent, Australia and the South Pacific. The majority are confined to South America and this, with other geographical evidence suggests a South American origin for this genus. N. tabacum has a uniquely high proportion of alkaloids occurring as nicotine and is considered to have survived as a species by man's protection. Creation of new species through hybridization is a natural botanical occurrence. It is an accepted assumption that N. tabacum arose as a natural hybrid. N. sylvestris contributes one genome, but agreement on the other contributor is not agreed upon. Artificial creation of hybrids which results in 'synthetic tobacco' bear very close genetic similarity to N. tabacum. Cultivated tobaccos have changed immensely over time and it is unlikely that the forms of other species now available bear to close a resemblance to what existed in the distant past.(1)

Botany

Tobacco is normally grown as an annual and is potentially a woody, shrub like perennial. The tobacco plant has a very shallow root system which provides poor anchorage for the more extensive above ground development. The N. tabacum types are one of the smaller species of tobacco varieties. The leaves supply the most important economic value of the plant and are given the most attention by botanists. Although there is variation in leaf size and shape there is general uniformity of distribution, size and shape within cultivated types. Between types, size and shape may vary considerably but not in distribution. The characters which may include leaf shape , leaf angle to the stem, form of the leaf tip, attachment of leaf to the stem, structure of the attachment and leaf asymmetry. In N. tabacum, ovate or oblong-lanceolate shapes are the most common and the leaves are most usually borne directly (sessile) on the main stem. The leaf surface has a matte appearance. The calyx is not of notable significance but the corolla extends much beyond it and is fairly characteristic. The tabacum colour is usually pink. The five stamens are attached to the corolla tube and bear oval-shaped anthers on the ends of long filaments. The stigma is likewise borne on the end of a long style that rises to just above the mouth of the corolla. The flower structure is very simple, being biased towards self fertilization but it is also easy to manipulate for cross breeding purposes. Most tobacco plants produce about 25 square feet of usable leaf.(1)

Modern Use

The tobacco leaf is used in many forms today. It can be rolled into cigarettes or cigars to be smoked or kept almost whole or ground up to be chewed or snorted. Tobacco is believed to be first used by the natives in the new world (Americas) by chewing or snorting the leaves for medicinal purposes by shamans or medicine men. It was not until later that it was smoked. Tobacco swept across Europe after Columbus discovered the natives in the late 1400's. Nicotine is the primary stimulant for man and is the primary alkaloid in N. tabacum. Nearly all of the nicotine is produced in the roots and is transported to the leaves for storage. It is not clear why nicotine is produced by the plant other than it might be a relic of part of a growth or development process which has been lost in evolution.(1) In any case it is the nicotine content in the leaves which attracted man to the tobacco plant.

In the early use of the plant the leaves were ground up or grated and either snorted through the nose or placed between the lip and gums and sucked. The use of tobacco was performed by men and women as a way to relax after a meal or as a medicinal agent for headaches. The plant must be topped at an early age. This is the removal of the leading stem to prevent the plant from flowering and seeding to starve the leaves. The suckering of the plant must take place, which is removing the suckers or shoots that appear at the junction of the leaves to the stem.(1) This ensures a high quality of the leaves that have already been established. Once the plant is fully-grown and the time is right the plant is severed near the ground and laid out in the sun for about a day to properly dry. Once the leaves are wilted or until the leaves are flaccid and will bend without breaking, the plant is then hung in a room to dry further, for about a month, or laid out to ferment. The leaves are removed from the stem and the main vein is removed from the leaf. The leaf is now ready to be manufactured. This whole process of drying and preparing is called 'curing' the leaf. Virginia or Burley tobaccos are primarily used for chewing tobacco and snuff. Fire curing, which is the use of fire amidst the hung plants to add flavor, is the curing process used in snuff production.(3) The leaf destined for snuff is generally kept whole or cut into strips. The dried leaves must undergo a severe fermentation of about two months. The tobacco is cut into one to two inch strips. The fermented tobacco is then completely dried and ground into a fine powder, which is then filtered through a silk blotting cloth. The powder can be of various textures depending on the company producing the final product. Various flavoring compounds can be added to some snuffs such as cherry, spearmint or mint flavor and is added during the grinding process. The newly ground tobacco is then ready to be sold. It is packaged in either plastic or hard cardboard containers. Each container is then sold for about three to four dollars at almost any store across the country.

Conclusion

The use of tobacco can be detrimental to the user. Its use has been linked to various forms of cancer and the loss of teeth. So, why has man been using and profiting from the plant for so long It is very hard to stop using tobacco after the user has been using tobacco in whatever form. Just ask a long-time smoker or chewer. Don't start is the best advice that I would have for anyone considering to start the use of tobacco. It is without a doubt the nicotine in the plant, which makes it addictive and a hard habit to break no matter how harmful the use of tobacco may be to the user. The money profited from the manufacture of tobacco is significant. The people making this money will not stop producing this product until its demand is nil. The tobacco plant has survived for a very long time and its use has been around for a long period of time. Tobacco plants will continue to be produced and processed for a long time to come. The use of tobacco shows how unintelligent man is because we keep using it even knowing its detrimental effects. The tobacco plant remains to this day one of the most important economic crops in the world.

References

1) Akehurst, B.C. Tobacco, Longmans, Green and Co., London. 1968 pages 2-11.

2) Fairholt, F.W. Tobacco: It's History and Associations, Chapman and Hall, Piccadilly, London. 1968, all pages.

3) Vogues, Ernst. Tobacco Encyclopedia, Tobacco Journal International, Federal Republic of Germany, 1984, all pages.

4) Britannica Online, Southern Illinois University, Morris Library.

EBL HOME PAGE