Physiological responses and expression pattern of SOS genes of bread wheat to salt stress

Regulation of ionic homeostasis in plant cells is one of the important aspects in salt tolerance. In this study, the effect of 200 mM salinity stress after 1, 10 and 20 days of stress on some morphological characteristics, elements concentration and expression of some genes involved in salt tolerance of bread wheat genotypes, including lines 7 and 8 (salt-tolerant), line 16 (salt-sensitive) and Sistan cultivar (native tolerant cultivar) were studied factorially in a Completely Randomized Design (CRD) with three replications. The results showed that salinity stress reduced shoot biomass in all tolerant and sensitive lines with the lowest reduction in line 7. Under salt stress conditions, Na+ content had an increasing trend in all lines and K+ content had a decreasing trend. The lowest increase of Na+, and the lowest decrease of K+ and K+/Na+ ratio was observed in line 7. Under salt stress conditions, the highest expression of SOS1, SOS2 and SOS3 genes was observed in line 7 and the lowest expression was observed in lines 16 and 8. The results of this study suggest that line 7 had a higher degree of tolerance and can be considered in breeding programs as well as for additional studies in saline areas.