Exogenous ABA Enhances the Antioxidant Defense System of Maize by Regulating the AsA-GSH Cycle under Drought Stress

When drought occurs during the maize-filling period, probability of yield decline increases. Abscisic acid (ABA) plays a regulatory role in physiological and metabolic activities plant development. However, its effect on antioxidant system maize leaves grain-filling stage is unclear. Maize plants (Zhengdan958) were used as an experimental material, ABA was sprayed stage. The placed under conditions to analyze relationship between ascorbate-glutathione (AsA-GSH) cycle hydrogen peroxide (H2O2) removal. Exogenous significantly reduced malondialdehyde content, relative electrolyte leakage, H2O2 stress. This similar exogenous AsA-GSH cycle. upregulated transcription related genes alleviated inhibition stress monodehydroascorbate reductase dehydroascorbate activities, thereby further increasing ascorbate peroxidase glutathione activities. It contributed increase AsA GSH levels inhibited decrease AsA/dehydroascorbic GSH/oxidized ratios. Therefore, important improving capacity resistance physiology by enhancing enzyme activity stabilizing redox state.