Evaluation of drought stress tolerance in promising lines of chickpea (Cicer arietinum L.) using drought resistance indices

Introduction Chickpea (Cicer arietinum L.) is an annual grain legume or “pulse crop” that is 2th legume after soybean in the world and was cultivated in 60 country. Legume, spatially chickpea is the most important tolerant crop in arid and semi-arid country in western of Asia such as Iran. Chickpea can growth in poor soil and undesirable environment conditions. Drought is an important factors that influencing chickpea production and quality. As area of cultivation is in dryland conditions thus aim of researches is reach to tolerant genotypes. The objective of current study was to evaluate the genetic variation and drought resistance advanced genotypes in chickpea Materials and methods For investigation of genetic variation and drought resistance, 64 advanced genotypes were evaluated in a simple latis (LD) with two replications under normal and drought stress conditions in deputy of Dryland Agricultural Research Institute of Kermanshah during 2013-2014 cropping season. Plant spacing was as plots with four rows in 4 m in length, 30 cm apart. The seed were sowed in row with 10 cm distance and the seeding rate was 33 seeds per m2 for all plots. At maturity stage after separation of border effects from each plot, grain yield was measured. Statistical analysis was performed using SAS, SPSS and STATISTICA packages. some drought resistance indices such as mean productivity (MP), geometric mean productivity (GMP), harmonic mean (HAM), stress tolerance index (STI), stress susceptibility index (SSI), yield index (YI), K1 and K2 were measured based on yield in both conditions. Also we used stress tolerance score (STS) method for selection genotypes according to all indices. Results and discussion Study on correlation between Yp, Ys and drought resistance indices showed that Yp and Ys had positive and significant correlated with MP, GMP, STI, YI, HAM, K1 and K2 thus these indices were the most suitable drought tolerance criteria for screening of chickpea genotypes and STI was used for 3D graph. According to drawing of 3D graph and bi-plot, the genotypes were placed into tolerant and non-tolerant groups, as genotypes FLIP 08-42C, Azad, Adel and FLIP 08-35C were placed near to MP, GMP and STI vectors and A group in area with high yield potential and low sensitive to drought. Also according to results of stress tolerance score (STS) method, above genotypes were selected as tolerant genotypes. For more understanding and visualizing the relationships between calculated indices and genotypes performance, principal component analysis (PCA) was performed. Result of this analysis showed that the first two components explained more than 98% of the total variance. Conclusions Finally, this high variation between studied genotypes could use in breeding program for reached to drought tolerant genotypes.