Genetic diversity studies among maintainers and restorers on milo and maldandi cytoplasm from minicore collection of sorghum using D2 statistics

Abstract

Sorghum is the important cereal crop around the world and hence understanding and utilizing the genetic variation in sorghum 
accessions are essential for improving the crop. The D2 statistics was applied to assess the diversity among 41 B-lines and 43 R
lines of sorghum identified from minicore collection. The analysis of variance revealed significant differences among the 
genotypes for all the characters under study. The genotypes were grouped into 13 clusters, where cluster III comprised maximum 
of 14 genotypes followed by cluster IV with 7 genotypes each among R-lines whereas B-lines grouped into 6 clusters with cluster 
I with 22 genotypes followed by cluster II with 9 genotypes. Inter-cluster distance was maximum between the clusters IX and X 
with 648.07 among R-lines and in B-lines maximum intercluster distance was between I and VI with 1136.00 which indicated 
that genotypes included in these clusters may give heterotic response and thus better segregants. Regarding genetic divergence of 
the genotypes, panicle weight (32.07 %), SPAD readings at maturity stage (29.76 ) and 100 seed weight (20.49 %) contributed 
major share among R-lines and incase of B-lines panicle weight (49.49 %), primaries per panicle (25.13 % ) and 100 seed weight 
(10.77 %) contributed high towards genetics. These traits can be utilized for selection of individual B-lines and individual R-lines 
for future crop improvement programme.