551 Evaluation of Vegetable Soybeans for Green Bean Yield and Nutritional Quality

Abstract

In Asian countries and among the oriental populations in the United States, vegetable soybeans are consumed much the same way as green peas are consumed. A need exists for developing soybean cultivars adapted to the U.S. environments to take advantage of the economic potential of vegetable soybeans for both domestic and international markets. During 1997, 12 vegetable soybean genotypes of exotic origin and two local U.S. soybean cultivars were evaluated for their agronomic performance in a randomized complete block, with four replications, at the Agric. Res. Stn. FVSU, Ga. At the R6 stage (when the seeds are of full size and still immature), plants from a half-meter-row length were sampled from each plot to estimate green pod and seed yield, and determine the nutritional quality of green beans. Significant differences were observed among genotypes for the agronomic and biochemical parameters studied. The green seed yield ranged from 7.1 (cv. Ware) to 14.0 Mg·ha–1 (cv. Tanbagura). Three cultivars, Tomahamare, Mian Yan, and Tousan-122, produced green seed yields in excess of 12 Mg·ha–1. The number of green pods varied between 1518 (Tanbagura) and 3526/m2 (cv. Hutcheson). The green bean oil and protein contents, ranged from 53.1 to 105.4 and from 354.2 and 418.3 g·kg–1, respectively. Thus, the green seeds contained only 30% of oil, but 50% to 80% of protein normally found in mature soybean seed. The glucose content was between 4.1% and 7.0%, while the phytate content varied between 0.93% and 1.3%. T he green seed yield was significantly correlated with number of green pods, number of green seeds, and green pod weight. This study showed that some exotic vegetable soybean genotypes may be suitable for production in the southeastern U.S.