Estimation of genetic divergence among sorghum germplasm of Pakistan through multivariate tools

Abstract

Sorghum is an important fodder crop with high biomass production potential all around the world including Pakistan. Genetic divergence was estimated among 208 sorghum genotypes of Pakistan by evaluating fourteen different quantitative traits for one year. High variability was reported in fresh biomass (35.60-629.12 g), dry biomass (23.41-367.72 g), flag leaf area index (37.61-407.39 cm2), leaf area index (94.71-1061.74 cm2) and plant height (106.14-298.27 cm). All the quantitative traits showed high broad sense heritability. The first three principal components (PCs) with Eigen value > 1 shared 75.39% variability of traits among sorghum genotypes. Positive correlation was observed between plant height and days to maturity, whereas fresh and dry biomass had significant positive correlation with leaf area index, number of leaves per plant, flag leaf area index, days to maturity and 50% days to flowering. Un-weighted Pair-Group Method of Analysis (UPGMA) revealed 141 morphotypes. The germplasm was grouped in to seven classes based on homology. The genotype P-13-2013 gave the highest values for number of leaves/plant, stem thickness, leaf length, fresh biomass, dry biomass and flag leaf area index. The explored genetic potential of sorghum germplasm of Pakistan can be helpful for varietal improvement program. Moreover, the diverse set of genotypes can be screened through principal component analysis for structure and association mapping by using molecular markers.