Like some other crops of long domestication, the relationship of the modern soybean to wild-growing species can no longer be traced with any degree of certainty. It is a cultural variety (a cultigen) with a very large number of cultivars. However, it is known that the progenitor of the modern soybean was a vine-like plant that grew prone on the ground.
The genus Glycine Willd. is divided into two subgenera(species), Glycine and Soja. The subgenus Soja(Moench) includes the cultivated Soybean, G. max(L.)Merrill, and the wild soybean, G. soja Sieb.& Zucc. Both species are annual. The soybean grows only under cultivation while G. soja grows wild in China, Japan, Korea, Taiwan and Russia. Glycine soja is the wild ancestor of the soybean: the wild progenitor. At present, the subgenus Glycine consists of at least 16 wild perennial species: for example, Glycine canescens, and G. tomentella Hayata found in Australia and Papua New Guinea [1]
Beans are classed as pulses whereas soybeans are classed as oilseeds. It is a versatile bean, having a diverse range of uses.