Study of General and Specific Combining Ability in Kharif Maize (Zea mays L.)

Abstract

The present investigation was carried during kharif  (July–October) 2024 at college farm Bihar Agricultural University, Sabour, Bihar, India utilizing twelve lines and two testers along with twenty four crosses to analyse general and specific combining ability. The experimental material comprised twelve lines and two testers, which were crossed in a Line×Tester mating design to generate twenty-four single-cross hybrids. The resulting twenty-four hybrids, along with fourteen parents and two standard checks, were evaluated in a Randomized Block Design (RBD) with three replications. Analysis of variance for combining ability revealed that SCA variance was higher than GCA variance for grain yield and most of the yield-contributing traits, indicating the predominance of non-additive gene action in the inheritance of these characters. Significant variation among the genotypes was observed for grain yield and its associated traits. Among the parental lines, SML 131, SML 45, SML 189, SML 66, SML 65, SML 4 and HK 1209 exhibited significant positive GCA effects in the desirable direction, identifying them as promising parents for developing high-yielding hybrids. Seven cross combinations, namely SML 131×LM 13, SML 45×LM 13, SML 36×LM 13, HK 1209×LM 13, SML 189×LM 14, CLO 2450×LM 14 and CLRCQY 44×LM 14, recorded significant positive SCA effects for grain yield and important agronomic traits, indicating their superior hybrid performance. Among these, SML 131×LM 13, SML 4×LM 13 and SML 189×LM 14 outperformed the standard check for grain yield. These hybrids possess considerable potential for exploitation in hybrid breeding programmes and should be evaluated through multilocation trials for their possible release as high-yielding single-cross maize hybrids to enhance kharif maize productivity in Bihar.