In order to evaluate drought tolerance of chickpea genotypes and identifying the best indices of drought tolerance, an experiment was conducted at two regions of research field in Mashhad Collage of Agriculture and Agricultural Research Station in Nishabour in 2003 growing season. The 34 genotypes were tested using a randomized complete block design under two irrigated (non stress) and rainfed (stress) conditions. Quantitive drought tolerance and susceptibility indices such as Stress Tolerance Index (STI), Stress Susceptibility Index (SSI), Mean Productivity (MP), Harmonic Mean (HM), Tolerance Index (TOL) and Geometric Mean Productivity (GMP) based on yield in stress and non stress conditions were calculated. Significant differences were found among the genotypes for drought tolerance indices with exception of TOL and SSI .
The highest yield was found in genotype numbers of 4,5,16,17,18,19 and 31 respectively genotypes ICCV 93040, ICCV 93042, MCC 13, MCC 448, MCC 5, MCC 10, MCC 16 in non stress conditions but genotype numbers 4,16 and 19 showed merely the highest yield in stress conditions in two regions. Results of regression analysis showed that MP,GMP,STI and HM indices had positive and high significance correlation with yield in stress and non stress conditions . Theses results indicate that MP,GMP,STI and HM are the most suitable criteria for screening drought resistant genotypes. Base on these criteria , genotype numbers of 4,16 and 19 that have the highest yield in stress and non stress conditions and rest near to vectors of drought resistance indices like MP,GMP,STI and HM in multivariate biplot space, Therefore, these genotypes may be recommended as drought tolerant genotypes in this study. |