Yam

Most of the yams are believed to originate from Southeast Asia and West Africa. Some taxonomists have suggested that there was an early separation in the Discorea development into old and new world species, which were reflected in cytological differences. The genus Dioscorea is the largest genus in the family Dioscoreaceae, including about more than 500 species. Edible yams are rich in carbohydrates and are a good source of protein, more than other tuber crops. Its tubers contain almost all the essential nutrients, including minerals, vitamins and amino acids. Yam is still processed by conventional method though there is a need to modernize processing and utilization of yam. Yam tubers are used as a folk medicine in China, Korea and Japan as it has antispasmodic properties. It helps in curing the nausea of pregnant women. Yam is a deciduous perennial plant. Yam plants produce tubers or rhizomes, from which, the vines and roots emerge annually during the growing season.