Effects of Exogenous Chitosan on Physiological Characteristics of Potato Seedlings Under Drought Stress and Rehydration

Using young plants of the potato variety "Favourite", we studied the effects of exogenous chitosan (CTS) on physiological characteristics of potatoes under drought stress and rehydration. Spraying 50, 100 and 200 mg l(-1) of exogenous CTS on potato leaves before drought stress reduced membrane relative permeability and malondialdehyde concentration of potato leaves, raised the concentration of proline and soluble proteins and enhanced the activities of superoxide dismutase and peroxidase during drought stress. Additionally, CTS promoted the recovery of these physiological indicators after a rehydration period. Of the three treatments, 100 mg l(-1) of CTS alleviated drought stress the best. Altogether, this indicates that exogenous CTS could relieve drought stress damage in young potato plants by enhancing their antioxidation ability, increasing the activities of protective enzymes and regulating the content of osmotic regulatory substances. Applying exogenous CTS could be an effective measure to reduce drought stress in potato and warrants further evaluation in the field.