Defining Selection Indices for Drought Tolerance in Chickpea under Terminal Drought Stresses

Abstract

Chickpea improvement for drought tolerance requires reliable assessment of drought tolerance variability among different genotypes. In order to evaluate quantitative drought resistance criteria in some chickpea breeding lines, thirty five genotypes were evaluated both under moisture stress (E1) and non-stress (E2) field environments using a randomized complete block design for each environment. Seven drought tolerance indices including stress susceptibility index, stress tolerance index, tolerance, yield index, yield stability index, mean productivity and geometric mean productivity were used. The significant and positive correlations of Yp and (MP, GMP and STI) and Ys and (MP, GMP and STI) under both the seasons as well as significant negative correlation of SSI and TOL in E1 revealed that selection could be conducted for high MP, GMP and STI under both environments and low SSI and TOL under E1 conditions. The calculated correlation coefficients revealed that STI, MP, and GMP are the superior criteria for selection of high yielding genotypes both under E1 and E2. Results of calculated gain from indirect selection indicated that selection from moisture stress environment would improve grain yield in moisture stress environment better than selection from non-moisture stress environment

Keywords

• Chickpea, drought stress, tolerance index, grain yield