The soybean,(ind:
Kedelai) glycine max, is a leguminous crop grown in many parts of the world and is of great economic significance as a source of edible oil and of high protein foods and stockfeed. It is a cultigen (a species created through cultivation) and is not known in the wild. Its wild ancestor is believed to be G. ussuriensis, a rambling vine native to northeastern Asia. Like many leguminous crops, the soybean has lost the winding and climbing growth pattern of its wild relatives. It is an erect, bushy herb growing to a height of 30 – 90 cm (1-3 ft) and developing profusion of roots that may reach up to a meter or more (3-4 ft) in loose soils.
Soybeans do not tolerate frost and are photoperiod-sensitive, which means that flowering cannot begin until summer nights grow longer. Plants require abundant moisture and, in the absence of irrigation, do not do well in areas of winter precipitation such as
Europe and Pacific America. Soybeans can be grown in nearly all types of soil but do best in fertile loams. Depending on the variety, soybean plants mature in 75 to 200 days. When used as a green manure, the plants are plowed under while still green. When used as hay, the soybeans are cut before they are completely ripe. After the leaves fall and the pods and stems dry naturally, the seeds are harvested with combines. Soybean seeds are hard, generally yellow, and pea shaped.
Soybeans are an important human food because they are unusually complete in proteins; of the eight essential amino acids, soybean contain seven in sufficient quantity and are deficient only in methionine, which can be supplied from wheat or corn. Soybeans are eaten in numerous ways- as a green or dried bean and as the constituent of soy milk, curds, cheese, and various sauces, and are major source of vegetable oil. Soybean protein is increasingly used as a meat imitation, or meat substitute. Soybean product are also important in animal feeds, and the green crop is used for hay, for forage, and as a fertilizer. Industrial uses include the manufacture of glycerin, paint, soaps, linoleum, rubber substitutes, plastics, and printing ink.