Physiological and Molecular Changes in Barley and Wheat Under Salinity

In this study, it was aimed to compare salinity-induced changes in barley (Hordeum vulgare L. cv. Bornova-92) and bread wheat (Triticum aestivum L. cv. Gerek-79). Seeds were germinated under saline conditions (0, 50, 100, 250, and 500 mM NaCl) for 2 days and recovered under non-saline conditions for 2 days. At the end of the salt treatment, germination, water content (WC), total soluble protein content, and catalase (CAT, EC 1.11.1.6) activity were affected in both species, while superoxide dismutase (SOD, EC 1.15.1.1) activity was affected in barley. Salinity affected WC, protein content, and CAT activity in both species, while it affected germination in barley and affected fresh weight and SOD activity in wheat after recovery. Physiological responses of both species were correlated. Expression of alpha-tubulin, Atls1, and Lls1 genes was down-regulated in barley after 250 mM NaCl treatment. HVA1 gene was highly (more than 50-fold) stimulated by salinity in barley. However, alpha-tubulin and Atls1 genes were down-regulated, and Lls1 gene was up-regulated in wheat after recovery from 250-mM NaCl treatment. Increase in HVA1 expression was not significant in wheat. The expression profiles of barley and wheat under salinity are different, and barley tended to regulate gene expression faster than wheat.