Psophocarpus

Psophocarpus is a small genus of flowering plants in the legume family (Fabaceae), subfamily Faboideae, native to tropical Asia and the western Pacific. The genus is best known for the winged bean, Psophocarpus tetragonolobus, a fast-growing climbing vine cultivated for edible pods, leaves, and seeds. In some classifications a second species, Psophocarpus scandens, is recognized or treated as a subspecies or variety of P. tetragonolobus.

Description: Plants are twining vines with pinnate leaves typically bearing three leaflets. Flowers form in inflorescences typical of legumes and are adapted to bee pollination. Fruits are pods; in the winged bean the pods have four distinct wings and are edible when young.

Distribution and habitat: Native to Southeast Asia and the western Pacific islands; widely cultivated in tropical regions of Africa, the Caribbean, and Oceania, especially in smallholder farming systems.

Uses and cultivation: Winged bean is valued for its multiple edible parts: the young pods, seeds, leaves, and shoots. It is noted for rapid growth and its ability to fix atmospheric nitrogen, which supports intercropping and soil improvement. It tolerates a range of tropical soils and is commonly grown as a multipurpose crop, often intercropped with maize, rice, or root crops.

Taxonomy: The genus belongs to the tribe Phaseoleae of Fabaceae and comprises a small number of species. Psophocarpus tetragonolobus is by far the best known and widely cultivated.