Monitoring of morphological, biochemical and molecular responses of four contrasting barley genotypes under salinity stress

Abstract

Salinity stress reduces crop growth and agricultural productions around the world. The effects of salinity stress on seed germination, some morphological, physiological and biochemistry traits, and expression of four genes at seedling stage in salt contrasting barley genotypes were investigated in the current study. Seed germination percentage and morphological traits were analyzed based on a factorial randomized complete design which ANOVA results showed that interaction between salinity (150 and 250 mM NaCl) and genotype (Afzal and Sahand (salt tolerant), and Fajr and Reyhan (sensitive)) was significat (p < 0.05). Also, physiological and biochemical traits were analyzed based on a factorial split plot based on randomized complete design which ANOVA results illustared that interaction between salinity, genotype and time (0, 12, 24 and 72 h after salt treatment) was significat (p < 0.05). Salinity stress significantly declined germination percentage, length and fresh weight of root and shoot, chlorophyll content while thiobarbituric acid reactive material ( TBARM), catalase activity, and proline values were increased in root and shoot of all genotypes at seedling stage. The aforementioned traits were more changed with increasing the salt concentration and the higher value of these traits except TBARM were observed in tolerant genotypes. Moreover, relative expression of four genes were investigated after 0, 12, 24 and 72 h of 150 and 250 mM NaCl treatments. The results revealed that expression of HvNHX3, HvCAT1, HvTIP2;3 and Hv3ARK were affected by salt stress and these genes play role in barley tolerance to mild and severe salinity stress based on their expression pattern.