Combining ability analysis for yield and related traits in Basmati rice (Oryza sativa L.)

Abstract

Line × tester experiment was conducted to evaluate the performance of 27 F1 hybrids along with 12 parents in Basmati rice. Analysis of variance revealed highly significant differences among treatments, parents, parents vs. crosses and crosses for number of tillers per plant, panicle length, number of grains per panicle, fertility percentage, 1000-grain weight and yield per plant. Lines were significant for number of tillers per plant, number of grains per panicle and 1000-grain weight while testers and lines × testers were significant for all the traits. The estimates of variance of specific combining ability effects, ratio of variance of general combining ability to specific combining ability and degree of dominance indicated preponderance of non-additive gene effects for each trait. On over all basis, role of testers in the expression of most of the yield components was more than lines and line × tester interaction. However, line × tester interaction contributed more than lines and testers for yield per plant. Three lines viz., Basmati 2000, Super Basmati and Kashmir Basmati and one tester Basmati-385 were identified as good general combiners based on their mean performance and GCA effects for yield and its various traits. Hybrids like Basmati Pak × Basmati-385, Super Basmati × Basmati-385, DM-107-4 × Basmati-385, Basmati 2000 × EL-30-2-1, Basmati 2000 × DM-25, DM-16-5-1 × Basmati-385 and Kashmir Basmati × DM-25 showed high mean performance, SCA effects and heterobeltiosis for grain yield and are proposed for heterosis breeding.