Comparing the Physiological Response of Four Wheat Cultivars to Salt Stress

The objective of this study was to investigate the effects of salt stress on osmotic adjustments and sodium concentration distribution in wheat (Triticum aestivum). Present study was performanced under greenhouse conditions. This study was carried out in factorial experiment design on the basis of completely randomized design in 3 replications. Four salinity levels were established: S =1.3dSm-1 (control), 5, 10, 15 dSm-1 from calcium chloride and sodium chloride with 10:1 (Na: Ca ratio) and another factor was genotype involved 4 cultivars, Sistani, Neishabour (tolerant) and Tajan, Bahar (sensitive). Sodium content and some osmolyte as prolin, protein and soluble sugar were measured at tillering and flowering stages. Total grain yield and yield components were determined. Results of mentioned traits at tillerig and anthesis stages indicated that Sistani and Neishabour had the higher value of protein and soluble sugar content under salt conditions, whereas Bahar and Tajan recorded the higher value of prolin and sodium content (at both stages). Grain yield, number of grain and 1000-grain weight of tolerant cultivars (Sistani and Neishabour) was higher than sensitive one. It can be inferred that in salt sensitive genotypes, the higher Na+ accumulation may generate ion toxicity and, subsequently the lower growth and plant yield. Bahar showed the highest Na+ content and the most reduction in the yield, thus it can be considered as more salt sensitive than Tajan.