Evaluation of drought resistance and determination of the best morpho-physiological traits in barley (Hordeum vulgar L.) as selection criteria to improve grain yield in cold dryland regions of Iran

In order to evaluation of drought resistance، 24 barley lines in drought stress and non-stress conditions planted in RCBD experiment with 3 replications. Along whole growing period all morphophysiological traits also recorded. The results of statistical analysis showed that: Stress Tolerance Index (STI) and Geometric Mean Productivity (GMP) are the best drought indices. Based on these indices lines Yesevi-93 (Abidar)، CWb22-6-13/ICB-102893، ICB-111877 identified as drought tolerant lines with high yield. On the other hand two-row barley is more drought tolerance than six-row barley. In evaluation of morphophysiological traits in drought stress conditions، STI and GMP indices have positive correlation with heading period length، plant height، awn length، harvest index، 1000-grain weight and grain-No per spike and negative correlation with grain filling period length.