Effect of calcium chloride and salicylic acid on antioxidative responses of lentils (Lens culinaris Medik.) under salt stress

Salinity causes physiological and morphological harmful effects in plants. The present study was conducted to investigate the effect of calcium chloride (CaCl2 0, 50, and 100 mM) and salicylic acid (SA 0, 0.75, and 1.5 mM) on the physiological characteristics of salinity stress (0, 25 and, 75 mM NaCl). The results of this research showed that the adverse effects of salinity were improved by calcium and salicylic acid. Also, root and shoot length, dry and fresh weight, carotenoids, and chlorophylls decreased under salt stress, while proline, inhibition of DPPH radical, malondialdehyde (MDA), and anthocyanine increased. However, calcium and salicylic acid increased dry and fresh weight, the root and shoot length, reducing sugars, carotenoids and chlorophylls, and significantly reduced inhibition of DPPH radical and malondialdehyde in lentils. The present research showed that calcium and salicylic acid promote salinity tolerance, which could be related to regulating antioxidant responses. According to the stated results, it can be suggested that the most appropriate concentrations for improving the physiological parameters of lentils under salt stress are 50 mM calcium concentration and 1.5 mM salicylic acid concentration. Therefore, SA and Ca play this role by regulating the antioxidant system.