Genetic divergence for agronomic traits in common bean lines evaluated in multiple experiments

Abstract

The effects of genotype × environment interaction on the clustering pattern of common bean genotypes for multiple agronomic traits have been underinvestigated by breeding programs. This study aimed to evaluate whether the number of experiments influences the clustering pattern obtained using the complete linkage (Farthest Neighbor) and Ward hierarchical methods for agronomic traits in common bean genotypes, as well as to identify the most promising parents for crossing. For this purpose, plant architecture and yield-related traits important for selection were assessed in Mesoamerican common bean lines across four experiments. Analysis of variance and clustering analyses using the Farthest Neighbor and Ward methods were performed with data from individual experiments and from combinations of two, three, and four experiments. Significant differences for genotype, environment, and genotype × environment interaction were observed for several agronomic traits. The traits contributing most to genetic divergence and to the clustering pattern of genotypes varied according to the number of experiments considered. Plant height and grain yield were the descriptors that most effectively differentiated the genotypes. The Farthest Neighbor and Ward methods showed 100% agreement in grouping bean genotypes when mean data from four experiments were used. The cross between line CNFP 18552 and cultivar IPR Urutau is promising for obtaining recombinants with upright plant architecture and high grain yield.