Genotype × Environment Interactions and Yield Stability of Food-Grade Soybean Genotypes

Abstract

Soybean [Glycine max (L.) Merr.], an important component of the Asian diet, is gaining popularity as a source of vegetable protein and phytochemicals in the USA. However, soybean cultivars with desirable agronomic traits and biochemical components that enhance the quality of soyfoods have not been identified for cultivation in the USA. Twelve soybean genotypes, including three from Japan, were evaluated for their agronomic performance, genotype × environment (GE) interactions, and yield stability at four locations in the USA from 1994 to 1997. At maturity, seed yield, biomass, harvest index (HI), and 100-seed dry weight were determined using plants harvested from the middle two rows of each plot. Genotypic differences for the traits examined were significant. The mean seed yield across locations and years ranged from 2.0 to 3.0 Mg ha⁻¹. The Japanese cultivars had larger seeds but were outyielded by the American genotypes by ≈10% and up to 35% by ‘Hutcheson’. The genotype effects were significantly larger than the location × year effects for plant height, seed weight, and HI, but not for biomass or seed yield. Biomass and HI were important determinants of seed yield. S90–1056, V81–1603, V71–370, ‘Enrei’, ‘Nakasennari’, ‘Ware’, and ‘York’ were stable for seed weight across years. Hutcheson, S90–1056, York, MD86–5788, Nakasennari, and BARC-8 showed yield stability across environments and years. S90–1056, York, and Nakasennari were stable for both seed weight and seed yield; therefore, they could be used for commercial production in the USA or for breeding soybean cultivars suitable for tofu preparation.