Evaluation of Moisture Deficit in Spring Barley Landraces North West of Iran

An experiment was carried for evaluating the effects of moisture deficit at different growth stages in spring barley landraces under field conditions. A split plot experiment was conducted based on randomized complete blocks design with three replications. Three irrigation levels including optimal and disruption irrigations at stem elongation and heading were arranged as main plots and barely landraces with names of Abdolalikandy, Bastam, Sefid, Seyah, Shin, Hashtpar and Bayramghalasi were in subplots. Different irrigation levels and barley landraces for measured traits showed statistically significant differences. Grain yield under optimal, disruption irrigations at stem elongation and heading were 161.14 g/m2, 99.8 g/m2 and 128.0 g/m2, respectively. Shin and Hashtpar landraces with the lowest grain yield 88.75 g/m2 and 95.91 g/m2 and amounts of the least TOL 12.5, 0.59 and SSI 5.0, 0.75 at both stresses were tolerant to moisture deficit. Spike/ m2 remained at final models in regression analysis at two moisture deficits. In principal components analysis, three first components explained more than 91% of total variance which they were named grain yield, physiological and morphological components, respectively. Grain yield was positively significant correlated with spike/m2 under optimal and disruption irrigations at stem elongation and heading with 0.94**, 0.90** and 0.94**, respectively. In both stresses, STI, MP, GMP and HAR indices had significant positive correlation with grain yield. In addition, spike/ m2 and plant height had the most direct effects on grain yield 0.84 and 0.29, respectivel