Heterosis and combining ability analysis for yield and its components in rice (Oryza sativa L.)

Abstract

Study of heterosis and combining ability were conducted on 40 F1 hybrids along with of 2 CMS lines (females), 20 diverse rice varieties/genotypes as testers (males) to know the pattern of inheritance of some morphological traits for selecting superior genotypes. The experiment was carried out according to line x tester mating design. Analysis of variance revealed significant differences among genotypes, crosses, lines, testers and line x tester interactions for all the ten traits, viz., days to 50% flowering, flag leaf area, plant height, panicle bearing tillers plant-1, panicle length, spikelets panicle-1, grain yield plant-1, test weight, biological yield plant-1 and harvest index. The highest heterosis (197.81%) was observed in cross IR 688897A X Sarjoo 52 followed by other eight crosses for yield and most of its related traits. Among the testers high gca was recorded in Sarjoo 52 and Narendra Usar 3 for harvest index, grain yield plant-1, days to 50% flowering (earliness), plant height (dwarf stature), panicle bearing tillers plant-1 and biological yield. Among the female parental lines, IR 58025 was observed as a good general combiner only for seedling height, panicle length, spikelets panicle-1, test weight, biological yield palnt-1. Cross between IR 688897A X Sarjoo 52, IR 58025 A X 21-2-5-B-1-1, IR 58025 A X Narendra Usar 3 and IR 58025 A X IR 71829-3R-73-1-2-B shown favorable per se performances and higher significant positive sca effects in related to grain yield plant-1.These combinations proved to be good hybrids based on CMS system in rice.