Combining ability studies through Line × Tester design in sweet sorghum (Sorghum bicolor L.) for bioethanol production

In developing of sweet sorghum hybrids, non-additive genetic effects are important in phenotypic expression of the traits of interest. The present experiment was undertaken to assess the combining ability in sweet sorghum genotypes using 16 hybrids developed by crossing four CMS lines with four elite testers in a Line × Tester mating design. The hybrids were evaluated at three locations in Andhra Pradesh in a Randomized Block Design with two replications during Rabi, 2018. Among the 13 quantitative characters studied the non-additive genetic variance was higher than the additive variance for all the traits except for days to 50% flowering, days to maturity, plant height and ethanol yield. Among parents, ICSA 14029, ICSA 14030 (females) ICSV 15006 and GGUB-28 (males) were found to be good general combiners for ethanol yield and its related traits with consistent performance across locations. ICSA 14029 × ICSV-15006 and ICSA 14033 × SEVS-08 were identified as superior crosses for the specific combining ability for high ethanol yield.