Improving the Physiological and Biochemical Properties of Two Pistachio Cultivars by Application of Potassium Sulfate and Nanopotassium Fertilizers under Salinity Stress Conditions

In order to evaluate the effects of potassium sulfate and nanopotassium fertilizers on two pistachio cultivars under salinity stress a factorial experiment was conducted in a completely randomized design with four replications. Treatments were three levels of salinity (0.5, 8 and 12 dSm-1) and potassium sulfate fertilizer (1 and 2%) and nano–potassium fertilizer (1 and 2 g L-1). The results showed that Akbari cultivar had the highest total chlorophyll, root potassium and proline contents compared with AhmadAghaei cultivar. The highest chloropyll conten was observed in Akbari cultivar under 0.5 dSm-1 NaCl by application of 2 g L-1 nano–potassium fertilizer. The lowest root sodium content was belonged to Akbari cultivar at 0.5 dSm-1 salinity stress with application of 1% sulfate potassium fertilizer. The minimum and maximunm content of proline was related to the salinity of 0.5 dsm-1 in AhmadAghaei cultivar and 12 dSm-1 in Akbari cultivar, respectively. The highest proline content was obtained by application of 2 g L-1 nano–potassium fertilizer. Application of potassium fertilizers reduced the adverse effects of salinity on pistachio seedlings.