Effect of Potassium Supply on the Activity of Some Antioxidant Enzymes of Two Durum Wheat Cultivars under Salt Stress

Potassium plays an important role in improving plant tolerance to a biotic stresses such as salt stress. In order to evaluate the effect of potassium on alleviating the adverse effects of salt stress by monitoring the activity of some antioxidant enzymes, the grain yield and chlorophyll content of two durum wheat cultivars (Behrang and Yavarous), a pot experiment was carried out based on randomized complete block design with three replications with treatment levels including: control (no salt), 150 mm NaCl (Sodium Chloride), salt 150 mm NaCl with two levels of 300 and 450 mg K kg-1 soil as potassium sulfate and two levels of 30 and 45 mg K kg-1 soil as nano chelate potassium 27%. The grain yield of both cultivars was decreased under salt stress, but the combination of potassium and NaCl alleviated symptoms of the individual salt stress by enhancing the activities of antioxidant enzymes compared with individual salt stress. Both cultivars showed similar responses to salinity in combination with forms and rates of potassium under stress conditions for some traits, a though the activity of acerbate peroxides and glutathione reeducates was higher in Behrang cultivar. Totally, these findings showed that salinity in combination with forms and rates of potassium was more effective in Yavarous than in Behrang cultivar.