Family Solanaceae

Family Solanaceae, popularly known as the potato family, is a large and economically important family of herbs, shrubs and, occasionally, small trees, distributed widely across tropical, subtropical and even temperate regions. Solanum nigrum (makoi) is often used as the representative plant to illustrate the family's characters, though several of its cultivated relatives -- potato, tomato, brinjal -- are far more familiar.

Vegetative characters. The stem is generally herbaceous, occasionally slightly woody, aerial, erect, cylindrical, branched, and either solid or hollow, with a surface that may be hairy or smooth (glabrous) depending on the species; in potato, however, the stem is modified into an underground storage tuber, a clear illustration that stem modification (covered earlier in this chapter) and family membership are independent classifications. Leaves are alternate, simple (occasionally pinnately compound), without stipules, and show reticulate venation.

Floral characters. The inflorescence is solitary, axillary, or a cyme. The flower is actinomorphic and bisexual. The calyx has five sepals fused together (gamosepalous), notably persistent -- it remains attached even as the fruit develops and matures -- and shows valvate aestivation. The corolla likewise has five petals fused into a tube (gamopetalous), also showing valvate aestivation, and is often funnel-shaped or wheel-shaped (rotate). The androecium has exactly five stamens, matching the corolla's five petals in number, each individually attached to the inner surface of the corolla tube (a condition called epipetalous) and alternating in position with the petals rather than sitting directly opposite them. The gynoecium is the family's single most diagnostic feature: it is bicarpellary (formed of two carpels) and syncarpous (the carpels fused together), and the resulting ovary -- superior, bilocular -- is placed obliquely on the floral axis rather than sitting straight and symmetrically, with axile placentation and a swollen placenta bearing numerous ovules in each chamber.

Fruit. The fruit is typically a many-seeded berry, as in tomato and brinjal, though in some genera such as Datura it is instead a capsule. …