Microsomal P450-related Electron Transfer Components, Glutathione and Glutathione S-transferase Contribution in Stress Response of Herbicide-treated Wheat to Drought and Waterlogging

Abstract

The activities of some plant microsomal P450-related electron transfer components (NADPH-cytochrome P450 reductase, CPR and NADH-cytochrome b5 reductase, B5R), glutathione S-transferase (GST) together with the content of reduced (GSH) and oxidized (GSSG) glutathione were determined in wheat (Triticum aestivum L., cv. Sadovo 1) treated with herbicide Serrate^® prior to drought or waterlogging. Both stresses, especially drought, increased the content of glutathione and the activities of CPR and B5R during the stress, while GST activity was rather decreased. Herbicide application alone increased substantially most of the parameters, especially at the beginning of the experimental period. Serrate^®+drought/waterlogging (S+D/W), amplified the observed alterations (except for GST), which were more significant after drought. The decrease in ratio GSH to GSSG after 4 days of recovery for all treatment groups except Serrate^® signifies disrupted buffer capacity in cells. After 4 days of recovery the activities of CPR and B5R dropped below the control, while the glutathione pool and GST activity remained increased in drought and S+D treated plants. Contrariwise, the levels of glutathione, CPR and B5R remained closer to control in waterlogged plants, while S+W kept higher levels of P450-related enzymes. The herbicide application prior to drought or waterlogging did not affect negatively detoxification and oxidative status of wheat plants compared to those subjected to water stress alone.