Genetic Analysis for Seed Yield and Its Components in Castor (Ricinus communis L.)

Combining ability analysis for ten characters was studied using line x tester mating design involving four diverse pistillate lines and ten inbred linesin castor. Combining ability analysis revealed that gca variances were significant for days to 50 per cent flowering, days to 50 per cent maturity, plant height, number of nodes up toprimary spike, length of primary spike, number of effective branches per plant, 100 seed weight, seed yield per plant and oil content, whereas sca variances were highly significant for all the characters except days to 50 per cent maturity. However, the ratio of s2gca/s2sca reveals the preponderance of additive gene action for days to 50 per cent flowering, days to 50 per cent maturity, plant height, number of nodes up to primary spike and oil content, while remaining characters showed predominance of non-additive gene action. VP 1 among the females was observed as a good general combiner for majority of traits, while among males JI 381 was observed as the best general combiner for seed yield per plant and its related yield components. Parents viz., Geeta, SKP 84, DCS 84, DCS 85and JI 381 were also observed as good general combiners for seed yield per plant and one or more of its related yield contributing traits. JP 65 and JI 387 were observed as the promising parents for imparting earliness and dwarfness. Based on the estimates of sca effects and per se performance hybrids viz., JP65 x JI 381, VP 1 x DCS 97 and Geeta x DCS 85 were found as the most promising cross combinations for exploiting the seed yield per plant.