Study morpho-physiological change and protein pattern of tolerant and susceptible wheat cultivars under salinity stress by using proteome analysis

In order to investigate the mechanism of tolerance to salt stress in wheat, a factorial experiment basis of completely randomized design with four replications in greenhouse media were conducted. The factors of this experiment were included salinity of sodium chloride in four levels of zero (control), 100, 200 and 300 mM and two wheat cultivars namely Niknejhad and Pishtaz as a representative of tolerant and susceptible cultivars, respectively. Leaf samples were prepared two weeks after the starting of salt stress. Then, extraction of protein from leaf tissue was done and two-dimensional electrophoresis in control plants and under salt stress plants were carried out. The results of proteome analysis revealed that 15 replicated protein spots with different expression variations were common between two tolerant and susceptible cultivars, and five protein spots of unique to each tolerant and susceptible cultivar, had significantly expression variations under stress. Protein spots were detected by mass spectrometry and the results showed that more number from commonly detected proteins were classified in functional groups including antioxidant defense and Calvin cycle, while other proteins in each cultivar had more roles in antioxidant activity. Overall, the results showed that there was a significant difference between two cultivars in terms of morpho-physiological response to salt stress, and the Niknejhad cultivar showed a better protein response under stress.