Stability and Environmental Responsiveness of WA-CMS Rice Hybrids for Yield and Grain Quality

Aims: To evaluate the yield performance, environmental responsiveness and stability of wild-abortive cytoplasmic male-sterile (WA-CMS)-derived rice hybrids for agronomic and grain-quality traits across three locations. Study Design: Multi-location evaluation in a randomised block design with three replications. Place and Duration of Study: Rajendranagar, Kampasagar and Kunaram during the kharif 2025 season. Methodology: Thirty-six hybrids developed from three WA-CMS lines and 12 restorers, together with 15 parents and four standard checks, were evaluated for 22 agronomic and grain-quality traits. Environmental indices, genotype means, regression coefficients (bᵢ) and deviations from regression (S²di) were summarised using the Eberhart–Russell stability framework. Inferential joint-regression tests must be confirmed from the original plot-level data before formal stability categories are assigned.Results: Environmental indices differed among locations and traits. For total grain yield, the indices were 0.001 at Rajendranagar, 0.038 at Kampasagar and −0.039 at Kunaram. CMS-59 × SN-2183 and CMS-59 × SN-2717 recorded the highest reported mean yield (0.59 kg plot⁻¹), followed by RMS-2 × SN-2183 (0.57 kg plot⁻¹) and CMS-64 × SN-2705 (0.55 kg plot⁻¹). Their regression coefficients indicated contrasting responses to environmental improvement. These entries are considered candidates for further evaluation rather than formally validated stable hybrids. Conclusion: The results provide a preliminary shortlist of WA-CMS-derived hybrids for further testing. Because the evaluation covered three locations in one season, and inferential stability statistics require confirmation, multi-year and multi-location validation is necessary before recommendation.