Exogenous hydrogen peroxide enhances the response of corn (Zea mays L.) plants to drought stress

Drought stress is a significant factor limiting crop growth and production. In this experiment, the effect of hydrogen peroxide (H۲O۲) application on water-stressed corn plants was investigated using various biochemical and molecular methods. Corn seedlings grown in hydroponic culture were treated with ۲ mM H۲O۲ and subsequently exposed to water stress using polyethylene glycol ۶۰۰۰ at three levels: ۰, -۲ bar, and -۴ bar. The results showed that drought stress significantly altered all of the studied traits. With an increase in stress levels, the activity of the catalase enzyme was decreased, and the highest drop, ۵۰%, occurred eight days after stress. It was revealed that catalase activity increased by up to ۱۸% on the second day after the stress, but it decreased significantly over time. The indigenous accumulation of H۲O۲ increased significantly in the -۴ bar treatment four days after stress, while it was reduced by ۵۰% on the eighth day post-stress. It was revealed that H۲O۲ application increased PAO gene expression ۱.۷ fold compared to the control plants. Its expression was decreased by ۳۵% at -۴ bar in control plants, while H۲O۲ treatment increased its expression by ۲.۸ times. These results indicate that H۲O۲ application enhanced tolerance to drought stress in corn plants.

Keywords:

Antioxidant enzymes , corn , Drought stress , Hydrogen peroxide