DETERMINATION OF AMELIORATING EFFECT OF SALICYLIC ACID ON TOXICITY OF ALUMINUM IN WHEAT ROOTS

This study revealed the role of salicylic acid (SA) in aluminum-induced physiological and biochemical changes in wheat root tips. The germination percentage was not significantly affected at 0, 2, 5, 8 and 10 mM Al. Root growth was inhibited with increasine, Al concentration, whereas cell death (dyed with Evans Blue) and lipid peroxidation increased. Changes in the activities of antioxidant enzymes (superoxide dismutase (SOD), catalase (CAT), ascorbate peroxidase (APx), guaiacol peroxidase (GPx)) were seen to depend on the increasing aluminum concentration, and this may suggest oxidative stress caused by aluminum. The activity of SOD, CAT, and GPx increased significantly while the activity of APx decreased. It was determined that treatment with 5 mM SA together with aluminum improved the toxic effect of aluminum. Therefore, increase in root growth and APx activity but a decrease in lipid peroxidation, cell death and SOD, CAT, GPx activities were observed. According to the results of this study, the toxic effect caused by Al on the physiological and biochemical parameters in wheat root tips was clearly ameliorated with SA treatment (5 mM).