Abstract:
Genetic variability in crop species is important for improving the crops and enhancing
production. Therefore, 36 common bean genotypes were evaluated for growth, yield and
yield related traits, at Arba Minch and Areka, Southern Ethiopia during 2022 in main
cropping season (July up to September). The field experiment was laid out in 6x6 simple
lattice design. Soft wares used for data analysis were Anova using proc lattice model with
sas 9.3, for mean comparison DMRT and for principal component analysis and clustering
Minitab. The analysis of variance revealed significant (p<0.01) differences among
genotypes. The variations observed among genotypes for grain yield ranged from 1537.5
kg/ ha for ADP0081 to 4747.7 kg/ha for ADP0570 with the overall mean value of 2934.3
kg/ha. High values of heritability (H2b) and genetic advance as percent of mean (GAM)
along with high genotypic coefficient of variation (GCV) for the traits like number of
seeds per plant, seed yield per hectare, harvest index, seed yield per plant, pod per plant,
seed per pod, plant height, internode length, above ground biological yield per hectare
suggesting that environment had brought no significant effect on the above traits
considered as favourable traits for common bean improvement through effective
phenotypic selection of these traits and high expected genetic gain from selection for
these characters can be achieved. Seed yield showed a positive and significant phenotypic
and genotypic association with seed per pod, number of seeds per plant, seed yield per
plant and above ground biological yield per hectare. This indicating these traits could be
the main contributors to grain yield. Principal component analysis (PCA) revealed that,
the first six components accounted for (71%) of the total phenotypic variation among 36
common bean genotypes evaluated for fourteen quantitative traits. The genotypes were
clustered into four groups, indicating the presence of genetic variability among the tested
genotypes of common bean following the phenotypic traits under consideration. In
conclusion, this study’s result showed that sufficient genetic variability among the
common bean genotype studied, which could be used to improve the yield and other
agronomic traits of the crop through selection or hybridization.
