Melatonin-Induced Salinity Tolerance by Ameliorating Osmotic and Oxidative Stress in the Seedlings of Two Tomato (Solanum lycopersicum L.) Cultivars

Melatonin is a crucial biological hormone associated with many physiological and biochemical processes in plants and also enhances resistance against various abiotic stresses. However, the mechanisms underlying the melatonin-assisted mitigation of salt stress in tomato (Solanum lycopersicum L.) plant are still poorly understood. A hydroponic experiment was conducted to investigate the protective role of melatonin in two tomato cultivars (Roma and FM9) under a highly saline growth medium (160 mM NaCl). The one level of melatonin (1.0 µmol L −1 ) was applied exogenously, sole, or in combination with the salinity stress. NaCl-induced phytotoxicity significantly ( P