Evaluate the effect of chitosan on the activities of antioxidant enzymes in Ajwain (Carum copticum L.) under drought stress

Today, the use of chitosan as one of plant hormones to increase plant resistance to stresses such as drought has been increased. In order to evaluate the effect of different levels of chitosan on antioxidant enzyme activities in Ajwain under drought stress, the experiment was conducted as split plot based on randomized complete block design with Three replications in research farm of Zabol University in 2014. Drought as the main factor in three levels A1) 50 mm evaporation (control), A2) 100 mm evaporation (medium stress) and A3) 150 mm evaporation (severe stress) of pan evaporation class A and different levels of chitosan spray (control, 0.1, 0.5, 1, 2 g/L) were considered as Sub factor. In this study, by increasing period between two irrigations, the activities of Catalase, Peroxidase, Ascorbate Peroxidase, Gayacolperoxidase, and polyphenoixidase enzymes were increased. There was no significant difference between control and moderate stress for most parameters but maximum activities of Antioxidant Enzymes were observed in severe stress. Using different levels of chitosan caused to improve the activity of antioxidant enzymes, so that, the interaction effect of 0.5 g/l chitosan and drought stress had increased most parameters significantly than that for control.