COMBINING ABILITY ANALYSIS FOR YIELD AND ITSCOMPONENT TRAITS IN RICE (ORYZA SATIVA L.)S.R. Sruthi, M. Surendhar, J. Johnny Subakar Ivin, Greetty Williams and Y. AnbuselvamAbstract The identification of superior parental lines is the pre-requisite for hybrid rice technology. The currentstudy used Line X Tester analysis to evaluate seven lines and three testers (ten parents) along with 21 F1hybrids in order to identify good combiners and cross combinations for the development of best high yielding++++++++++++++++++++++varieties. The variances due to line x tester differ significantly for all the traits indicating thepredominance of inherent variability among all the cross combinations. The GCA/SCA variance ratio wasless than one for all the traits studied, suggesting the predominance of dominance (non additive) geneaction governing the traits. The estimates of combining ability variances revealed that SCA variance washighly significant than the GCA variance as observed from the GCA/SCA ratios for all the traits studiedwhich indicated the preponderance of non-additive gene action. Among the parents lines based on themean performance of different parental genotypes, the lines ADT-42, ADT-39 and ADT-45 while the testersADT-36 and Ilupai poo samba were adjudged as good general combiner for grain yield/plant and severalimportant traits to emerge as superior parents for hybridization programme for obtaining high yieldingvarieties. Among twenty-one hybrid combinations, three crosses viz., ADT-45 x ADT-36, ADT-39 x ADT-36and ADT-45 x ADT-48 were highly significant and positive specific combiner for grain yield per plant andits component traits and were found suitable for heterosis breeding. |