Vigna

Vigna is a genus of plants, legume family Fabaceae, with a pantropical distribution, named for the seventeenth-century Italian botanist Domenico Vigna, director of the Orto botanico di Pisa, and comprising at least 90 species divided across the subgenera Ceratotropis, Haydonia, Lasiospron, Plectrotropis and Vigna. Members are herbs or occasionally subshrubs with pinnate leaves divided into three leaflets, producing racemes of yellow, blue or purple flowers followed by legume pods; notable cultivated species include the adzuki bean, black gram, cowpea and mung bean, distinguished from the related genus Phaseolus by differences in biochemistry, pollen structure and other traits.