Correlation and Path-Coefficient Analysis of Component of Agronomic Characters in Lima Bean (Phaseolus Lunatus)

Abstract

Phenotypic variance, genotypic variance, genotypic-phenotypic variance ratio and environmental-genotypic variance ratio were estimated for 30 Lima bean accessions in Ghana. The characters studied were number of days to pod maturity, pod length, number of seeds per pod, 100-seed weight, number of pods per plant, seed width, seed length and seed yield per plant. A large proportion of the phenotypic variance of number of days to pod maturity (78%), pod length (99%), number of seeds per pod (99%), 100-seed weight (99%), number of pods per plant (60%), seed width (98%), seed length (95%) and seed yield per plant (87%) was attributable to genotypic differences among the accessions. Phenotypic and genotypic correlations were of the same sign in all cases. Correlations among number of pods per plant was significantly and negatively correlated with number of days to pod maturity (P < 0.05), pod length (P < 0.001), 100-seed weight (P < 0.001), seed width (P < 0.001) and seed length (P < 0.001). Number of days to pod maturity and number of seeds per pod had a positive direct relationship with seed yield per plant. Pod length, number of pods per plant, 100-seed weight, seed width and seed length had negative direct effect on seed yield per plant. There was significant correlation between seed size and the other characters, thus, suggesting possible pleiotropic effects of genes controlling seed size and these other characters. Selection for high seed yield per plant through high number of days to pod maturity would result in reasonably high seed yield per plant without sacrificing pod length, seed per pod, seed weight and seed width. High number of days to pod maturity would mean that the plant would stay longer in the soil to increase soil fertility as a result of nodulation. Therefore, there is the double benefit of soil fertility and high seed yield.