Heterosis, Combining Ability and GXE interactions in Sweet Sorghum

Combining ability analysis revealed predominance of non-additive gene action for days to 50 per cent flowering, days to maturity, plant height, brix per cent, total soluble solids, total sugar index, juice yield, juice extraction per cent and grain yield. Therefore heterosis breeding is suggested for these traits whereas additive gene action is important for total biomass, fresh stalk yield and ethanol yield hence, simple selection would be effective for these traits. Among the parents, RS 1220B, CSV 19SS and SSV 74 were found to be good general combiners, while the cross combinations viz., NSS 1007A CSV 19SS and NSS 1016A SSV 84 showed good specific combining ability coupled with high per se performance for ethanol yield. Hence, highly suitable for heterosis breeding. Based on stability, the hybrids viz., NSS 8A SSV 84 and NSS 1007A CSV 19SS for ethanol yield, juice yield and total biomass were found to be stable with well adaptation to all environments.