Abstract:

In order to evaluate the effect of sulfur on the composition and accumulation of 7S and 11S globulin subunits, the best phosphorus levels of different genotype soybean varieties were explored to increase the content of dietary fiber and improve their qualities. Three soybean varieties (‘Heinong48’, high-protein cultivar; ‘Heinong37’, middle cultivar; and ‘Heinong44’, high-oil cultivar) grown more in Heilongjiang Province were investigated. The soybean seeds were planted in pots. Four levels of sulfur (S) treatment were designed, which were S1, S2, S3 and S4 (i.e., 0, 0.02, 0.04, 0.06 g of sulfur per kilogram of soil). The composition and accumulation of mature soybean seed proteins was determined by conducting SDS-PAGE. It showed that: the 7S globulin comprised of 4 subunits of α′, α, γ, and β; and 11S globulin comprised of acidic and basic subunits in the three soybean varieties. No significant differences were observed between the varieties with regard to the molecular weights of the globulin subunits. The concentration of the globulins in the same variety was the highest under the S3 treatment, while they were the highest in high-oil cultivar in different soybean varieties. S fertilization has no effect on the 7S and 11S globulin subunits of soybean cultivars and has only a slight effect on the molecular weights of these subunits. Significant differences were observed in the concentrations of 7S and 11S globulin subunits with the S-nutrition in the three varieties. These findings suggest that appropriate amounts of S fertilization might contribute to the increased concentrations of both soybean globulins and their subunits.