Exogenous application of penconazole regulates plant growth and antioxidative responses in salt-stressed Mentha pulegium L.

摘要

The mechanism of growth amelioration in salt-stressed pennyroyal (Mentha pulegium L.) was investigated by exogenous application of penconazole (PEN). Seven weeks after sowing, seedlings were treated with increasing NaCl concentrations (0, 25, 50, and 75 mM) with or without PEN (15 mg l?1) and were harvested randomly at different times. Results showed that some growth parameters and the relative water content (RWC) decreased under salt stress, while lipid peroxidation, H2O2 content, activities of superoxide dismutase (SOD; EC 1.15.1.1), peroxidase (POX; EC 1.11.1.7), polyphenol oxidase (PPO; EC 1.10.3.1), catalase (CAT; EC 1.11.1.6), and ascorbate peroxidase (APX; EC 1.11.1.1) remarkably increased. Exogenous application of PEN increased some growth parameters, RWC, antioxidant enzyme activities, and H2O2 content, but the effects of PEN were more significant under salt stress conditions. PEN treatment also decreased lipid peroxidation. These results suggest that PEN-induced tolerance to salt stress in M. pu...