Evaluation of salicylic acid pretreatment and salinity effect on some physiological and biochemical parameters in Triticum aestivum L

Salicylic acid (SA), a plant phenolic compound is considered as a hormone like endogenous regulator, and its role in the defense mechanisms against biotic and abiotic stressors has been well characterized. This experiment was conducted to investigate the impact of SA on growth, physiology and biochemical parameters of Triticum aestivum grown under combined stress of salinity. For this purpose, Triticum aestivum L (Shiraz and star cultivars) seeds were soaked in SA (0, 0.5 and 1 mM) and then salinity applied by NaCl (0, 100 and 200 mM). FW (fresh Wight), photosynthetic pigment and total protein contents decreased sharply with increasing stress levels. prolin, MDA and H2O2 contents increased significantly under saline condition. However, seeds pretreated with salicylic acid along with the salinity levels showed enhancement in growth parameters, photosynthetic pigments, and total protein contents while, proline, MDA and H2O2 levels decreased. The results showed that salt-induced deleterious effects in Triticum aestivum seeds were significantly encountered by the pretreatment of salicylic acid. It is concluded that salicylic acid improves the adaptabilities of Triticum aestivum plants to NaCl stress.