Phenotypic variation and estimation of genetic parameters for plant growth, fruit quality traits and bacterial blight disease resistance in gamma () irradiated seed derived progenies and germplasms of pomegranate (Punica granatum L.)

Abstract

In order to improve fruit quality traits in a breeding programme, both genetic and environmental effects need to be evaluated. The partitioning of variance and genetic parameters for fruit quality traits and disease resistance were estimated in 475 accessions of pomegranate by considering the effects of genotype, environment and their interactions. The results showed that genotype contributed most to the variance except to leaf thickness, flower length, flower breadth, number of arils per fruit and seed length, Genotype and environment interactions were significant for all traits except for plant spread, leaf thickness, fruit length and rind thickness indicating the influence of environment on the attributes of pomegranate fruit. High heritability, along with genetic advances in days to maturity of fruit, Anthocyanin content, phenolic content, rind thickness, volume of juice, plant spread, plant height and acidity suggested that there were significant additive gene effects for such traits. In general, the genotypic co-efficient variances were lower in magnitude than the corresponding phenotypic co-efficient variances for all traits. The estimates of PCV and GCV were high for fruit weight, total aril weight, number of arils per fruit, volume of juice, hundred aril weight, single aril weight, acidity, anthocyanin, phenolic content and bacterial blight on fruits, indicating greater scope for improvement of these characters by simple selection. High heritability and high genetic advance as percent of mean was observed for days to maturity, plant spread, volume of juice, rind thickness, acidity, phenolic content, anthocyanin content bacterial blight on fruit, stem and disease severity.