Genetic diversity analysis for shoot fly tolerance traits in Rabi sorghum [Sorghum bicolor (L.) Moench]

Mahalanobis D2 statistics was applied to assess the divergence among 121 Rabi sorghum genotypes. The analysis of variance revealed significant differences among the genotypes for all the traits studied. Among the 12 quantitative characters studied trichome density on lower leaf surface contributed maximum (34.60 %) to the total divergence. All the genotypes were grouped into seven clusters, cluster I was the largest with 74 genotypes, followed by cluster II (29 genotypes), cluster III (10 genotypes), cluster IV (5 genotypes), remaining clusters, viz., cluster V, VI and VII were solitary in nature. Maximum intra cluster distance was shown by cluster IV (5.06), and the maximum inter cluster distance (10.91) was noticed between the clusters III and VII indicating that the crosses between accessions of these different clusters could manifest heterosis and better recombinants after hybridization.