It is a large family, commonly called ‘potato family’ with 90 genera, and 2000 species including 60 from India. It is widely distributed in tropics, subtropics and even temperate zones.
Vegetative Characters
Habit: Plants are herbs or undershrubs and some of them are climbers.
Root: Taproot, well developed, branched. Stem: Erect, branched, herbaceous or woody, solid, cylindrical, hairy or glabrous.
Leaves: Cauline or ramal, simple, exstipulate, petiolate or sessile, arranged alternately, rarely opposite, pinnatisect in tomato, unicostate, reticulate venation. Floral Characters Inflorescence: Solitary, axillary, umbellate or helicoid cyme as in Solanum.
Flower: Bracteate or ebracteate, pedicellate, complete, hermaphrodite, pentamerous, actinomorphic and hypogynous.
Calyx: Sepals five, gamosepalous, tubular or campanulate, persistent, green or coloured, hairy.
Corolla: Petals five, fused, tubular or infundibuliform, aestivation valvate or imbricate, coloured.
Androecium: Stamens five, epipetalous, anther introrse, dithecous, basifixed or dorsifixed, filament deeply inserted in corolla tube.
Gynoecium: Bicarpellary, syncarpous, ovary superior, obliquely placed, placentation axile, with many ovules in each locule, style simple, stigma bifid or capitate. Fruit: Capsule or berry with endospermic flat seeds.
Economic Importance
1. The family includes many species cultivated for their edible fruits or tubers, such as the tomato, potato, eggplant and chilli pepper. 2. Deadly nightshade (Atropa belladonna) yield belladona for relieving pain externally, cough and excessive perspiration internally and atropine for dilating pupil. The root is the basis of the principal preparations of belladona. 3. Tobacco comes from the dried and cured leaves of Nicotiana tabacum. It is chewed, smoked or snuffed. Tobacco is intoxicant and stimulant but is habit forming and increases the incidence of heart trouble, lung cancer, and gum cancer, impotency in males and infant deformities in smoking mothers. Tobacco contains the alkaloid nicotine, a powerful neurotoxin that is particularly harmful to insects. 4. Henbane (Hyoscyamus niger) plant contains a relatively high concentration of alkaloids primarily atropine, hyoscyamine and scopolamine. It is used extensively as a sedative and pain killer and is specifically used for pain affecting the urinary tract, especially when due to kidney stones. 5. Roots of Ashwagandha (Withania somnifera) are used to cure rheumatism and general weakness. 6. Thornapple (Datura stramonium) gives an alkaloid called stramonium for relaxing bronchial muscles. 7. Some plants like night jasmine (Cestrum nocturnum), Poorman’s orchid (Schizanthus pinnatus), Petunia, are grown in garden for their beautiful flowers.
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