Index-Based selection of Chickpea (Cicer arietinum L.) genotypes for enhanced drought tolerance

Chickpea, a protein-rich legume grown primarily in tropical and subtropical regions, faces significant challenges due to drought stress. A field study was conducted over two years (2020-21 and 2021-22) aimed to identify chickpea genotypes that are tolerant to drought. The study involved 25 chickpea genotypes subjected to irrigated (control) and water stress (drought) conditions and the experiment was arranged in a split-plot design. The study results indicated significant variation among the genotypes, water treatments, years, and their interactions. Multiple stress tolerance indices, association analysis, principal component analysis, biplot analysis, clustering, and ranking methods were employed to identify drought tolerant genotypes. The stress tolerance index (STI), mean relative performance (MRP), and relative efficiency index (REI) were identified as the most effective indicators for pinpointing genotypes with high yield potential under both experimental conditions. Genotypes viz., BDG75, BGD103, Digvijay, ICCV92944, ICC4958, and JG16 showed high drought tolerance, as evidenced by their favourable performance in terms of mean rank, standard deviation of ranks, and rank sum. Conversely, the genotypes ICCV96030, JG63, GNG1581, JG12, PG186, GG2, Pusa362, and SAKI9516 were found sensitive. Correlation analysis, ranking techniques, cluster analysis, PCA, and biplot analysis effectively distinguished between drought-tolerant and drought-sensitive genotypes. The biplot analysis further reconfirmed the notable drought tolerance of the BDG75, BGD103, Digvijay, ICCV92944, ICC4958, and JG16 genotypes. This study demonstrated that an index-based selection approach can be used to screen and identify chickpea genotypes that exhibit higher tolerance to water stress effectively and rapidly. Therefore, the findings underscore the potential of using selection indices as a viable strategy for enhancing drought tolerance in chickpeas.