Analysis of Nutritional Contents in Vegetable Soybeans

Abstract

ABSTRACT In addition to oil and soyfoods, soybean [Glycine max L. (Merr.)] is also produced for vegetable use. The importance of consuming vegetable soybean for the prevention of chronic diseases is well documented. The objectives of this study were to determine the magnitude of genotype x year interactions (GYIs) for nutritional values, to estimate broad-sense heritability (h2 BS), and to identify genotypes that have stable nutritional values. Thirty-one soybean genotypes from maturity groups (MGs) III to VI were grown at Randolph Research Farm of Virginia State University, Petersburg, Virginia, during three years. The genotypes were harvested at immature green pod stage (R6-R7) and analyzed for nutritional values (lipid, protein, fatty acid profile, and carbohydrate). Significant (P < 0.01) differences among the genotypes were found for protein, ratio (18:1/18:2 + 18:3), and carbohydrate (CHO). The GYIs were also significant (P < 0.01) for all the seed traits analyzed, indicating that the performance of the genotype changed from year to year. Moderate h2 BS estimates of 56%, 61%, and 69% were observed for protein, ratio, and CHO, respectively. These h2 BS indicated the seed traits analyzed were equally influenced by environments and genetic factors. In general, the percentage contribution of genotype to the total sum of squares was higher than that of the GYIs for all seed traits analyzed with the exception of lipid. Among the genotypes tested Akiyoshi ranked high in protein, ratio, and, CHO and PI 379621 ranked high in protein and CHO. These genotypes could be used as genetic source in improving nutritive values of vegetable soybean genotypes. The rank correlations between G ×; Y model analysis mean ranking and cultivar superiority performance measure (CSPM) value ranks for lipid, ratio, protein, and CHO were 0.912**, 0.979**, 0.987**, and 0.973**, respectively. This suggested that either method of analysis could be used in identifying genotypes with stable performance.