Improvement of vegetable soybean: genetic diversity and correlations of traits between immature and mature plants

Abstract

Human consumption of vegetable soybeans is increasing, and consequently, breeding programs need to be encouraged and optimized. Therefore, there is a need to understand the relationship between the traits evaluated in the R₆ (full seed) and R₈ (full maturity) stages and estimate genetic divergence. At two sites and two crop seasons, we evaluated 42 progenies (F₆ generation) from crosses between vegetable soybean genotypes and three commercial cultivars. In general, we found significant coincident correlations between environments. Positive and significant correlations between pod width (PWR₆) and hundred-seed weight (HSW) and between PWR₆ and hundred-pod weight (HPW) suggest the possibility of replacing the labor-intensive process of obtaining HSW and HPW by estimating PWR₆, which is faster and easier to apply. The unweighted pair-group method arithmetic average analysis allocated soybean genotypes into six major clusters. Furthermore, information from the present work may guide practical actions in breeding programs.

Keywords:
Glycine max; soybean breeding; edamame; Pearson correlation