Characterization of genetic variability among sorghum genotypes by morphological descriptors associated with high yield and shoot fly resistance

Abstract

Developing and identifying high-yielding genotypes with shoot fly resistance in sorghum is a complex task that requires a detailed examination of genetic variability and relationships between numerous component traits related to grain yield and pest resistance. The purpose of this study was to use 15 morphological traits to assess genetic variability in 64 sorghum genotypes, which were analysed using principal component analysis (PCA) and the box plot technique. PCA identified seven components that account for almost 74% of the total variability in grain yield and shoot fly resistance. Two of the most reliable components (PC1 and PC2) were strongly correlated with a number of traits, including deadhearts per cent (21 and 28 DAE), seedling vigour, number of eggs per plant and trichome density on upper and lower surfaces, fodder yield per plot, fodder yield per plant, days to maturity and days to 50% flowering. PCA biplots identify groups of genotypes that can be suitable for specific breeding strategies. These include genotype clusters that combine grain yielding ability with resistance to shoot flies. According to the results of the box plot analysis, most of the traits showed greater variation towards grain yield and shoot fly resistance. This research has provided useful information on sorghum genotype genetic variability and its potential use in sorghum development programmes.