Combining ability analysis and gene action of grain quality traits in rice (Oryza sativa L.) using line × tester analysis

Abstract

In rice, twelve lines were crossed with five testers in a line × tester mating design and the resultant 60 hybrids along with their parents were evaluated for their combining ability effects for 15 grain quality traits. The results revealed that the ratio of GCA: SCA variances computed for all the fifteen grain quality traits showed the predominance of non-additive gene action. Among the lines, ADT (R) 47 showed significant desirable gca effects at 1% probability level (p = 0.01) for 11 grain quality traits viz., hulling percentage, milling percentage, head rice recovery percentage, kernel breadth, kernel breadth after cooking, breadth wise expansion ratio, gelatinization temperature, amylose content, gel consistency, water uptake and volume expansion ratio. Among the testers, Pusa 1460 showed significant desirable gca effects at 1% probability level (p = 0.01) for 10 grain quality traits viz., kernel length, kernel breadth, kernel length/breadth ratio, kernel length after cooking, kernel breadth after cooking, linear elongation ratio, gelatinization temperature, amylose content, water uptake and volume expansion ratio and hence they were adjudged as the best combiners for the improvement of the respective traits. Among the hybrids, the hybrids CO 47/Imp., Samba Mahsuri, ADT (R) 47/IRBB 21 and ADT (R) 46/IRBB 21 were identified as best hybrids for exploitation of grain quality traits since they revealed significant sca effects at 1% probability level (p = 0.01) for eight, eight and five grain quality traits, respectively