Amin Abbasi

Drought is one of the major abiotic stresses limiting plant growth and crop production Ascorbic acid also plays an important role in responding to biological and abiotic stresses and controlling plant growth. Therefore, this study was conducted in order to investigate the effect of spraying ascorbic acid on the level of enzyme antioxidant activity under water stress conditions in the greenhouse of Maragheh University in 2021. This research was carried out as factorial experiment conducted based on a randomized complete block desing with three replications. The main factor includes water stress in three levels: 90% of field capacity (as nonstress condition), 60% field capacity and 30% field capacity. Also, the secondary factor includes control (no spraying of ascorbic acid) and spraying of ascorbic acid in 150 and 300 µM concentrations. The results obtained from this research showed that total superoxide dismutase and Mn-SOD, Fe-SOD and Cu/Zn-SOD isozymes were affected by the effect of intraction of water stress × ascorbic acid spraying. According to the results, the highest amount of measured traits was obtained from the spraying of 300 µM ascorbic acid at 90% field capacity. The lowest values of the traits are related to the no ascorbic acid spraying in the 30% field capacity. Therefore, according to the results obtained from this research, the ascorbic acid spraying at 300 µM concentration, especially in stress conditions, can be effective in increasing the plant's tolerance to adverse environmental conditions due to the increase in enzyme antioxidant activity.