Evaluation of genetic variability, heritability, genetic advance, and association of yield and yield contributing traits of indeterminate climbing common bean (Phaseolus vulgaris L.) genotypes

Despite the importance of common bean as a cash crop, research and development have given limited attention to the indeterminate climbing bean. As a result, its productivity has remained low due to a lack of improved varieties. Hence this study was undertaken to estimate the extent of genetic variability, heritability, genetic advance, and associations of yield and yield contributing to 12 quantitative traits of indeterminate climbing common bean genotypes. The study used forty-nine genotypes of indeterminate- climbing type of common beans with a 7x7 triple lattice design. Variance analysis revealed a highly significant difference among 49 genotypes of beans for twelve morphological traits (< 0.01) under study. The coefficient of variation, both at the phenotypic and genotypic levels, indicated significant differences among the genotypes for measured traits. The result revealed that estimates of heritability (%) in a broad sense for 12 traits studied, ranged from (23.73%) to (85.85%) for seed per plant and hundred seed weight respectively. Genetic advance estimation in this study revealed that plant height, pod per plant, branches per plant, biological yield, harvest index, 100-seed weight, and grain yield had high heritability estimates coupled with high genetic advance as a percentage of the mean. The correlation analysis revealed that grain yield had a highly significant and positive phenotypic correlation with plant height, pod length, pod per plant, seed per pod, seed per plant, branch per plant, hundred seed weight, biological yield, and significant positive phenotypic correlation with harvest index. Path coefficient analysis demonstrated that higher positive direct effects were exerted by biological yield harvest index and hundred seed weight on grain yield at phenotypic and genotypic levels. The study reveals significant genetic variability in indeterminate climbing common bean genotypes, highlighting the potential for selective breeding to enhance yield-related traits. By identifying high-performing genotypes, the research supports targeted breeding programs aimed at increasing productivity and benefiting smallholder farmers in Ethiopia.