Exogenous Acetylsalicylic Acid Stimulates Physiological Changes to Improve Growth, Yield and Yield Components of Barley under WaterStress Condition

To assay the effect of acetylsalicylic acid pretreatment on enhancement of yield and yield components of barley (Reihan-03) under water stress condition, an experiment was conducted as a spilt-plot arrangement based on randomized complete block design with four replications at the Research Field of Shahid Bahonar University of Kerman, Iran, in 2012-2013. Irrigation condition was arranged in main plots (normal irrigation and withholding irrigation at flowering) and acetylsalicylic acid (0, 0.5, 1 mM) in sub-plots. Water stress caused a significant reduction in relative water content, fertile spike/m2, kernels per spike, 1000 kernel weight, grain yield and biomass and increased electrolyte leakage of plasma membranes, proline content, catalase and also guaiacol peroxidase enzymes activity of flag leaf. Results showed that acetylsalicylic acid application brought on the increased levels of water stress tolerance in barley. Acetylsalicylic acid pretreatment increased antioxidant enzymes activity, relative water content, grain yield, biomass as well as proline content of flag leaf and reduced electrolyte leakage. The concentration of 1 mM acetylsalicylic acid was more effective. In conclusion, seed priming with acetylsalicylic acid increased the tolerance of barley to water stress condition via maintaining cellular membrane integrity and neutralizing or scavenging of reactive oxygen species.