Vol. 9, Special Issue 8, Part A (2025)

Standard heterosis plays a vital role in hybrid rice breeding, enabling the evaluation of hybrid performance relative to established check varieties. In this study, 36 rice hybrids were evaluated against three standard checks (US 312, RNR 15048 and JGL 24423) for 16 traits, including nine yield and yield-related traits and seven grain quality traits. Significant negative standard heterosis for days to 50% flowering and plant height suggests potential for early maturity and lodging resistance. Positive significant heterosis was observed for traits such as 1000-grain weight and grain yield per plant. Specific hybrids showed promise for breeding programs focused on enhancing productivity and grain quality.