Effect of Drought Stress on Grain Yield and Yield Components of Winter and Facultative Barley Genotypes in Maragheh Region

In order to evaluate morpho-physiological traits of advanced barley lines under drought stress and supplementary irrigation and the relationship of these traits with yield, twelve lines were studied in Maragheh Dryland Agricultural Research Station during 2009- 2010 in RCBD with three replications. Different morpho-physiological traits were assessed during growth period. Under drought stress, results showed considerable differences among lines for days to heading, number of seeds in main spike, number of unfertile spikelet, spike length and harvest index. Under supplementary irrigation, the lines differed for growth vigor, days to heading, 1000 kernel weight, fertile spikelet, spike length and weight, number and weight of seeds in spike, harvest index and grain yield. Number of spike/m2 (r = 0.68**) and germination percentage (r = 0.65**) showed significant and positive correlation with grain yield under drought stress. Under supplementary irrigation, plant height (r = 0.7*) and number of seeds in main spike (r = 0.59*) had positive correlation with grain yield. Drought tolerance indices such as STI, MP and GMP had highest correlation with grain yield under drought condition and SSI, TOL, STI, MP and GMP had the highest correlation with grain yield in terminal supplementary irrigation. Line No. 9 (TOKAK//STEPTO/ANTARES) with 2694 kgha-1 grain yield and high 1000 kernel weight was determined as a drought tolerance genotype.