Yield Based Drought Tolerance Indices Used To Identify Drought Resilient Rice Genotypes In Gokuleshwor, Baitadi, Nepal

Drought stress is a critical challenge to rice production, necessitating the development of drought-tolerant genotypes. This study aimed to evaluate 25 rice ( Oryza sativa L.) genotypes for drought tolerance under rainfed and irrigated conditions at, Baitadi, Nepal during June–October 2022, using an alpha lattice design. The experiment aimed to identify drought-tolerant genotypes and effective drought tolerance indices based on grain yield. Drought stress, induced at the reproductive stage, reduced yields by an average of 24.2% (range: 9.6–53.3%). Mean Productivity (MP) and Geometric Mean Productivity (GMP) emerged as the most reliable indices, showing strong positive correlations with yield under both conditions. Principal Component Analysis (PCA) and drought tolerance indices (TOL, MP, GMP, STI, YSI, SSI) identified CFFT-SPRING IR 10L192, CVT BORO IR 1621226, Rato Basmati, RAVI-DROUGHT IR 80991-B-330-0-1, and RAVI DROUGHT IR 129077-2-1-42-5-B as the most drought-tolerant genotypes, with high MP and GMP values and low stress susceptibility. These genotypes are potential candidates for breeding programs in the mid-hills of Nepal, supporting sustainable rice production under water-limited conditions.