GENETIC DISSECTION OF HETEROSIS FOR YIELD AND QUALITY TRAITS IN RICE USING LINE × TESTER METHOD

Abstract

This study was conducted to assess the magnitude of heterosis for grain yield and associated agronomic and quality traits in rice (Oryza sativa L.) using a Line × Tester mating design. Three lines and eight testers were crossed to generate twenty-four F₁ hybrids, which were evaluated along with their parents and a standard check during Kharif 2023 in a randomized complete block design. Analysis of variance revealed significant differences among genotypes for most traits, indicating substantial genetic variability. Significant positive heterosis was observed for grain yield and its component traits in several crosses. Notably, the hybrids NVSR-3537 × NWGR-19208, NVSR 3461 × NVSR-687, and NVSR-3537 × NVSR-796 exhibited high per se performance along with significant standard heterosis for grain yield. Desirable heterotic effects were also recorded for traits such as grains per panicle, harvest index, protein content, and amylose content, while negative heterosis for days to 50% flowering indicated potential for early maturity. The findings demonstrate the effectiveness of heterosis breeding in rice, the identified superior hybrids and parental lines can be utilized in future breeding programs aimed at developing high-yielding and quality rice cultivars, although multi-environment evaluation is recommended to confirm stability and adaptability.