Genetic variation for grain yield and water absorption in common bean (Phaseolus vulgaris L.)

Abstract

Common bean (Phaseolus vulgaris L.) is commonly grown crop in Ethiopia. Increasing bean grain yield partly
requires developing cultivars that are high yielding and high in water absorption. An experiment was carried out
using 26 common bean genotypes grown during 2005 cropping season at Jimma, Ethiopia, to investigate genetic
variances, broad-sense heritabilities and phenotypic correlation coefficients for grain yield and water absorption
traits. Pods/plant, 100-seed weight (g), grain yield (g/plant) and water absorption showed high values of genetic
variances. Genetic coefficients of variation ranged from 3.46(days to maturity) to 27.02 (water absorption). The
broad sense heritability of grain yield, pods, seeds and water absorption were 72.36, 90.61, 58.50 and 87.09,
respectively. The correlation between grain yield and pods/plant (r = 0.67; p = 0.01), and that of coat proportion
and water absorption (r = 0.43; p = 0.05) were significant. This experiment suggests that selection for pods/plant
could be used to improve grain yield per plant. Moreover, the presence of high broad-sense heritability values for
water absorption suggests the existence of opportunity to improve this trait in common bean.