Evaluation of sorghum RILs for moisture stress tolerance using drought tolerance indices

Drought is a leading cause of yield loss in important cereal crops in addition to adverse climate change. The development and cultivation of new drought tolerant varieties that can yield adequately under both well water and water stress environments is an important plant breeding goal and the objective of this experiment. Drought stress indices are one of the approaches for the identification and selection of stable, high-yielding and drought tolerant superior genotypes. The Plant Abiotic Stress Index Calculator (iPASTIC)- an online software that calculates common stress tolerance and susceptibility indices for various crop traits has been utilised for finding the superior genotypes using tolerance index (TOL), mean productivity (MP), harmonic mean (HM), yield stability index (YSI), geometric mean productivity (GMP), stress susceptibility index (SSI), stress tolerance index (STI), relative stress index (RSI), and yield index (YI). Here in this study two hundred seventeen RILs of E36-1 x Basavanapada were screened with the nine drought stress indices and differentiated all genotypes under well-water and water stress environments. Based on these indices, correlation and principal component analysis, top ten superior high yielding and drought tolerant genotypes were identified viz., RILs 129, 21, 146, 134, 22, 55, 4, 59, 45 and 92. These superior genotypes can further be tested for multi-location trials and in advanced breeding programs to develop varieties suitable for cultivation in drought prone regions.