Effect of Cultivar, Seed Size, and Crop Year on Total and Free Sugar Contents of Domestic Soybeans

Abstract

Investigations have been carried out to determine the effect of cultivar, seed size, and crop year on the total and free sugar contents of soybeans of 13 cultivars grown at the same location in the normal and unseasonable of two crop years. When the seed size decreased, total sugar, free type of total sugar, raffinose, and stachyose contents increased (102-116%), and the increased ratios of raffinose and stachyose were higher than those of other sugars. On the other hand, only sucrose content slightly decreased (93-99%). The cultivar, as compared with the seed size, was more influencial on the all sugars, and higher contribution ratios were observed in cultivar. The unseasonable year showed high in all sugar contents (103-122%), and the highest difference between the two crop years was observed in the sucrose content. Significant differences were observed in total sugar, free type of total suger, sucrose, raffinose, and stachyose among the cultivars, and in total sugar, free type of total sugar, and sucrose between the crop years. From the contribution ratio, crop year was higher than cultivar in all sugars except raffinose and stachyose.