Effect of Foliar Application of KCl and K2SO4 on Ameliorating Injuries Caused by Oxidative Stress in Rainfed Fig cultivar  Sabz'

Global warming and drought are the main causes of reduction in the production of fig in Iran. The situation is worse in dry farming areas. „Sabz‟ fig cultivar, which is mostly grown in dryland conditions in Fars province, has been afflicted by drought stress during the past few years. The aim of this experiment was to increase tolerance of fig trees to drought stress by foliar application of KCl and K2SO4. To this end,„Sabz‟ fig cultivar trees in Bidbokhoon sector of Neyriz town in Fars province were foliar sprayed with K2SO4 and KCl (0, 1.5 and 3%) in early growth season. Results indicated that application of K2SO4 and KCl at the rate of 3% increased potassium content, maximum quantum efficiency of photosystem II, total phenol, anthocyanin, carotenoid, protein and proline content in fig leaves and decreased superoxide dismutase and ascorbate peroxidase enzymes activity. The application of K2SO4 and KCl at the rate of 1.5% did not significantly affect the measured characteristics. Generally, the application of potassium sulphate and potassium chloride at the rate of 3% caused an increase adaption of fig trees against environmental stresses and there was no difference between the use of potassium sulphate and potassium chloride.