Evaluation of Genetic Diversity in Advanced Sorghum Genotypes for Yield and Yield-Related Traits
Yaddanapudi Meghana *
Department of Genetics and Plant Breeding, College of Agriculture, PJTSAU, Hyderabad, India.
S. Maheshwaramma
Seed Research and Technology Centre, PJTAU, Hyderabad, Telangana, India.
D. Shashibhushan
Department of Genetics and Plant Breeding, Regional Agricultural Research Station, Palem, Telangana, India.
M. Shankar
Department of Entomolgy, Regional Agricultural Research Station, Palem, Telangana, India.
*Author to whom correspondence should be addressed.
Abstract
The present study evaluated genetic divergence among 42 advanced sorghum genotypes during the kharif season of 2025 at the Regional Agricultural Research Station, Palem, Telangana. The experiment was laid out in a randomised complete block design with three replications, and observations were recorded for 12 yield and yield-related traits. Genetic diversity was assessed using Mahalanobis D² statistics, Tocher’s clustering method and principal component analysis. Analysis of variance indicated significant differences among genotypes for all traits studied, confirming the presence of variability in the experimental material. Based on D² analysis, the genotypes were grouped into seven clusters. Cluster I contained the largest number of genotypes (21), followed by Cluster III (8), Cluster IV (5), Cluster II (4) and Cluster VI (2), while Clusters V and VII were monogenotypic. The highest intra-cluster distance was recorded in Cluster III (13.14), whereas the maximum inter-cluster distance occurred between Clusters V and VI (294.77), indicating substantial divergence between these groups. Principal component analysis showed that the first three principal components explained 91.17 per cent of the total variation, with PC I, PC II and PC III contributing 77.20, 9.84 and 4.11 per cent, respectively. Plant height contributed the most to genetic divergence (56.21%), followed by number of grains per panicle (10.68%), 100-seed weight (8.47%) and grain yield (4.76%). Cluster mean analysis indicated that Cluster II had the highest grain yield, while Cluster V performed well for several yield-contributing traits. The genotypes PSV 803, PSV 757, PSV 769 and PSV 767 may therefore be useful parental materials for future sorghum improvement programmes.
Keywords: Sorghum bicolor, genetic divergence, Mahalanobis D² analysis, principal component analysis, Tocher’s method, cluster analysis, advanced genotypes, yield-related traits, grain yield, fodder yield, sorghum breeding