Peroxidase, Superoxide Dismutase and Catalase Activities of the Pistacia khinjuk Seedlings under Drought Stress

ABSTRACT The aims of this study were to assess the effects of drought stress on peroxidase (POD), superoxide dismutase (SOD) and catalase (CAT) activities as well as free proline content and growth parameters of Pistacia khinjuk seedlings under drought stress. Therefore, the one-year seedlings of Pistacia khinjuk subjected to water stress (25%, 50%, 75%, and 100 % field capacity) for 8 months in greenhouse condition. Results showed that drought stress decreased height, collar diameter, shoot dry weight and root dry weight of P. khinjuk seedlings. But it had different effects on antioxidant enzyme activities in root and shoot of P. khinjuk seedlings. Drought stress increased CAT activity in shoot and root of seedlings and its activity was higher in 25 % field capacity than other treatments. Also, the POD enzyme activity increased in root and shoot of seedlings subjected to drought stress. The SOD activity was at the lowest level in 100 % FC than other treatments. The results also showed that free proline accumulation was lower in well watered seedlings and increased under drought stress.