Studies on Combining Ability for Development of New Hybrids in Rice

Combining ability studies were conducted over locations and seasons on grin yield and yield contributing characters by utilizing line x tester analysis with four CMS (WA source) and well adapted seventeen elite diverse lines. The SCA variances were higher than GCA variances for majority of the characters over the seasons, revealed that preponderance of non- additive gene action. The estimates of gca effects showed that parents with high gca effects differed for various yield and yield components traits over the seasons and locations. IR-79156A, IR-68897 and tester R-51were performed well under different seasons and locations. Considering the yield and yield contributing traits promising general combiners for kharifR-47, R-48, R-49, R-52, R-56, IR-64 and IR-10198 and rabiR-42, IR-66, R-43, R-46, R-56 and IR-13419. Based on per se performance, sca effects (High x High or High x Low gca effects of each cross) hybrids viz., DRR-14A x R-54, IR-80555A x R-48, IR-80555A x R-49, IR-80555A x R-51, IR-79156A x R-44 and IR-79156A x R-48 suitable for kharif season. Cross combinations viz., IR-80555A x R-47, IR-79156A x R-43, IR-79156A x IR-13419, IR-68897A x R-48, IR-68897A x R-51 and IR-68897A x R-52 identified as promising rabifor season.