Grouping Different Wheat Varieties for Salt Tolerance using Some Biochemical and Physiological Indices

In attention to wheat importance in human nutrition and its production limitations due to salt stress, this study was conducted to evaluate and grouping 52 different wheat varieties for activities of antioxidant enzymes. Seedlings in 4-5 leaf stage, which were grown in aeroponic way, were exposed to salt stress using 200 mM NaCl for 10 days. After that, activities of enzymes of catalase, glutathione peroxidase, ascorbat dehydrogenase, superoxide dismutase isozymes along to amounts of malon dialdehyde and hydrogen peroxide, Na, K and Cl were measured. Cluster analysis categorized the varieties into three distinct groups. The varieties such as Karkheh, Arta and Alborz as a distinct group had the lowest values of catalase, hydrogen peroxide and malon dialdehyde, in addition to high values of antioxidant enzymes. However, accumulation of Na and Cl under salt stress was high in the varieties but damage severity decreased because of increase in antioxidant enzymes activity that led to stop oxidative stress. Also, it is very probable that they have a special ability in leaves to detoxification Na and Cl. These genotypes were known as tolerant varieties which those may be applied in wheat breeding programs for salt tolerance. Totally, each of the varieties had some appropriate tolerance mechanisms to defense with salinity and the results clarified genetic variation in this regard.