Combining Ability of TGMS Lines and Utilization of Heterosis in Rice (Oryza sativa L.)

An investigation was carried out with the objective of evaluation of twoline hybrids for heterosis and combining ability using four TGMS lines viz., TS09 12, TS09 22, TS09 28 and TS09 410 and thirteen testers by line x tester method. The checks used were Improved white ponni and CORH 3. The lines TS09 22, TS09 410 and the testers viz., CO 43, WGL 14 and Improved white ponni were found to be good general combiner for most of the yield contributing traits. The magnitude of SCA variance was higher than the GCA variance in all yield contributing characters, which indicated the presence of non-additive gene action governing the traits and need to exploitation of heterosis for further improvement. Per se performance and general combining ability studies revealed that the exact potentiality of TGMS lines and testers. The hybrids TS09 12 X CO 43, TS09 22 X CO(R) 49, TS09 22 X CO(R) 50, TS09 22 X T1408.10, TS09 22 X G 14, TS09 28 X CO43 and TS09 410 X T 360 were found to be promising for heterosis breeding programme. Based on the sca effects and heterosis, TS09 22 X T1408.10, TS09 28 X CO 43, TS09 12 X CO 43, TS09 22 X WGL 14 and TS09 22 X CO(R) 50 were identified as potential hybrids and these two line hybrid combinations could be utilized for commercial exploitation. The present investigation revealed that the TGMS system could be utilized for developing twoline rice hybrids.