Effects of salt stress on antioxidant system activity and peroxidation damage in root tip cells of strawberry

In this study, strawberry seedlings were treated with 250 mmol·L-1 NaCl solution; then the O2- production rate, the content of H2O2 and thiobarbituric acid reactive substance (TBARS), electrolyte leakage (EL), the enzyme activity of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) in the root tip cells were determined to be used for analysis after salt stress. The results revealed that the O2- production rate, EL, and the content of TBARS showed an increasing trend with the time of salt stress, while the content of H2O2, the enzyme activity of SOD, POD and CAT exhibited a pattern of increasing first and decreasing later under the salt stress. In conclusion, the results demonstrated that the oxidative damage in root tip cells of strawberry was increased with the time of salt stress, and the enhanced antioxidant activity was not enough to eliminate the peroxidation damage which was caused by 250 mmol·L-1 NaCl solution.   Key words: Strawberry root tip, salt stress, the activities of the antioxidant enzymes.