Exploitation of heterosis using diverse parental lines in Rabi Sorghum

Sorghum (Sorghum bicolor (L.) Moench) is one of the major crops for grain and fodder, widely grown in India under rain fed conditions. Rabi sorghum is grown in an area of 5.5 million hectares mainly in the states of Maharashtra, Karnataka and Andhra Pradesh with average productivity of 854 kg/ha. Despite low productivity, Rabi sorghum continues to be an important component of dry land economy in these states with fairly consistent area over many years. The low yields are mainly due to various abiotic and biotic stresses. Hybrid vigour and its commercial exploitation have paid rich dividends in Kharif sorghum leading to quantum jump in sorghum production. However, the progress in Rabi sorghum is limited and there is a need for critical studies on combining ability and heterosis involving diverse sources of breeding lines. Present study comprised a line x tester analysis involving 2 lines and 7 testers for exploitation of heterosis and assessing best combiners. Combining ability studies revealed the presence of significant differences due to lines, testers and line x testers, indicating the presence of variability. Considering the general combining ability effects of parents, female SL-19B and males SLR-13, SLR-24 and SLR30 were good general combiners for grain yield and the female SL-12B and male SLR-10 and SLR-27 were good general combiners for earliness. The crosses SL-19B x SLR-13, SL-19B x SLR-17, SL-19B x SLR-30 and SL-19B x SLR-39 were identified for improving grain yield and crosses SL-12B x SLR-10, SL-12B x SLR-27 and SL-12B x SLR-39 were selected for breeding earliness.