Effect of irrigation interval and chitosan spraying on some physiological characteristics and Antioxidant enzymes activity of common Mallow (Malva sylvestris)

In order to evaluate the effects of chitosan spraying and irrigation interval on physiological characteristics and antioxidant enzymes common mallow, a factorial experiment in a completely randomized design with three replications was conducted in 2015 at the Faculty of Agriculture, University of Zabol. The experimental treatments included irrigation interval (Irrigation interval 7 day, Irrigation interval 11 day and irrigation interval 15 day) and foliar chitosan spray (0, 0.5 and 1 mg.l-1). The results of interaction showed that spraying with 1 mg. l -1 chitosan during irrigation increased 27 and 7 % respectively, chlorophyll a and the relative content of leaf water and on the other hand spraying with 1 mg. l -1 chitosan during 15 day irrigation cause increased in total phenol content (79 %),proline (68 %) and Activity of antioxidant enzymes peroxidase (51 %), ascorbate peroxidase (72 %), guaiacol peroxidase (70 %), superoxide dismutase (54 %) and catalase (80 %) relative to the control. The results of correlation showed that proline had significant and positive correlation with RWC, but showed a negative correlation with photosynthetic pigments. Also there was a significant positive correlation between enzyme and non-enzymatic antioxidants.. The results of this study showed that chitisan spraying at the rate of 1 mg. l -1 reduced the lipid peroxidation, through increasing the antioxidant defense system activities of the plant and prevent the relative water content of the leaf through retaining cells’ water balance which, consequently, leads to cells’ structures stability against deficit stress.