COMBINING ABILITY ANALYSIS OF HARVEST INDEX AND ITS COMPONENTS IN SORGHUM

Abstract

Genetics of harvest index and its components was studied follOWing diallel approach. Seven genotypes having three maintainer of cytoplasmic genetic male sterile lines~ two improved varieties and one each improved local variety and restorer of CSH-10 were selected for crossing in half diallel fashion. Pooled combining ability analysts revealed that harvest index, grain yield and its related characters were governed by both additive and nonadditive gene action. Maintainer lines 296 B, M-9 Band 20Tl Bwere identified as most desirable general combiners for harvest index. Improved varieties Spy 472, SPY 475 and Vidisha 60-1 were identified as desirable combiners for grain yield. The cross combination Spy 475 x M·9 Bwas superior for harvest index and grain yield on the basis of sea effects. Hybrids with high harvest index and productivity can be bred by using lines already improved for these traits.