Foliar application of ascorbate enhances the physiological and biochemical attributes of maize (Zea mays L.) cultivars under drought stress

Maize (Zea mays L.), grown in different Asian countries, undergoes drought stress during the hot summer periods, which is the most common cause for reduced growth and yield of maize worldwide. A greenhouse experiment was conducted to investigate the prompting role of ascorbic acid (AsA) in maize drought-tolerant (Agaiti-2002) and drought-sensitive (EV-1098) cultivars under two drought stress levels (control and 65% field capacity). Ascorbate is essential for plants due to its function as antioxidant and protector against environmental stresses. The results showed that drought stress reduced the plant growth, fresh and dry biomass, and photosynthetic pigments of maize plants. Exogenous application of ascorbic acid lowered the drought stress-induced reduction in growth, biomass, and photosynthetic pigments. Drought stress enhanced the activities of superoxide dismutase (SOD) and peroxidase (POD) in maize plants, and application of AsA further enhanced the activity of these enzymes. The results indicate that foliar application of AsA alleviated the detrimental effects of drought stress in maize plants by improving the antioxidative defense system. The cultivar EV-1098 was found to be relatively resistant to drought stress. Our research suggested that foliarly applied AsA may be useful for the sustainable maize production under drought-stressed ecologies.