Abstract: Triadimefon increased the relative water content and decreased malondialdehyde (MDA) content under osmotic stress of – 0.5 MPa induced by PEG-6000. The activities of peroxidase (POD) and catalase (CAT) were induced by triadimefon at a concentration of 75 mg/L by root treatment under osmotic stress, but the superoxide dismutase (SOD) activity remained unchanged. Addition of cycloheximide, an inhibitor of protein synthesis, indicated that the activation of POD induced by triadimefon was due to the promotive effect of de novo enzyme synthesis. No effect of triadimefon on POD isozyme pattern was demonstrated on PAGE.

Key words: Rice, Peroxidase, Catalase, Superoxide dismutase, Drought resistance