Heterosis studies for yield and yield components using CMS lines in rice (Oryza sativa L.)

It is important to know the degree and direction of hybrid vigour for its commercial exploitation. Three lines were crossed with eight testers in line × tester mating design in rice. The resultant 24 F1s was evaluated along with their parents and check variety (Indira Sona and Karma Mahsuri)) to estimate heterobeltiosis and standard heterosis for yield and yield attributing traits. These crossesshowed marked variations in the expression of heterobeltiosis and standard heterosis for yield andyield components.Six crosses viz., IR79156/NPT-4, IR79156/NPT-38, CRMS31/R-1656-2816-9-3223-1, CRMS-31/NPT-1, CRMS 31A/NPT-17 and CRMS 32A/NPT-1 showed significant heterosis heterobeltiosis and standard heterosis for grain yield and yield attributing traits. these identified as promising hybrids for grain yield per plant.