Genetic assessment of combining ability for grain yield and key attributing traits in maize (Zea mays L.)

Abstract

Maize (Zea mays L.) is an important cereal crop globally, and enhancing its yield and associated traits is of paramount importance. Combining ability analysis is a valuable tool in crop improvement, allowing breeders to identify promising parent lines for developing superior hybrids. This study assessed the general and specific combining ability of ten maize inbred lines and three testers for grain yield and associated traits. A line × tester mating design was used, and thirty crosses were evaluated. Analysis of variance revealed significant differences among lines, testers, and line x testers for all studied traits, confirming the genetic diversity of the materials used. General combining ability (GCA) and specific combining ability (SCA) variances were significant, indicating the importance of both additive and non-additive gene effects. Notably, CML-425 showed significant positive GCA for grain yield, making it a potential parent for high-yielding hybrid development. Among the crosses, UMI-1200 × CML-451 exhibited desirable SCA values for grain yield. Understanding the combining ability effects of parent lines and their crosses is essential for breeding high-yielding maize hybrids. This study provides valuable insights for maize improvement programs, with the potential for significant yield enhancements.