Regional Differences in the Concentration of Water-soluble N in Immature Seeds of Soybean(Glycine max(L.)Merr.)

AbstractFour vegetable-type soybean (edamame) cultivars and four grain-type cultivars were cultivated in four prefectures, Iwate, Akita, Yamagata, and Fukushima in Japan. Concentrations of water-soluble N in immature seeds tended to be higher in vegetable-type soybean seeds than in grain-type soybean seeds in all four cultivation areas. However, immature seeds of a grain-type cultivar, Higomusume, which has a small grain size, had higher concentrations of water-soluble N comparable to those in immature seeds of edamame cultivars in all four cultivation areas. This suggests that the concentration of water-soluble N in some grain-type cultivars is determined mainly by genetic characteristics of cultivars. Higomusume may be an important genetic resource for further studies on the synthesis and/or accumulation of storage substances in immature grains.