Response of Pistachio Rootstocks (Pistacia Vera cv. Ghazvini) to Different Levels of Zinc and Sodium Chloride

The objective of this study was to evaluate the effect of zinc and salinity levels on some growth parameters and chemical properties of Pistachio (cv. Ghazvini). A factorial greenhouse experiment was carried out as a completely randomized design with three replications. Treatments were 4 levels of Zn (0, 5, 10 and 15 mg kg-1 soil as ZnSO4.2H2O) and 5 levels of salinity (0, 800, 1600, 2400 and 3200 mg NaCl kg-1 soil) and their combinations. Results showed that growth parameters decreased with increasing soil salinity so that the treatment 3200 mg NaCl kg-1 soil resulted in the mean dry weight reduction of the shoot, root, plant's height and the leaf area to the amounts of 33, 76, 14 and 35 percent respectively in comparison to control. Application of 10 mg zinc kg-1 soil increased an amount of 20, 71, 31 and 41 percent in the mentioned parameters respectively. With increasing salinity, shoot zinc and calcium concentrations significantly decreased by an amount of 48 and 30 percent, respectively, and shoot sodium concentration increased more than 7 times in comparison with the control treatment. As salinity increased, root zinc concentration increased from 17.56 in the control to 21.27 mg kg-1 in the highest salinity level. Shoot Ca concentration increased about 30 % at the third salinity level, but, at the highest salinity level, it was significantly reduced. Zinc application increased shoot zinc and calcium concentrations by, respectively, 60 and 34 % and reduced root Na concentration by 20 %. Also, salinity significantly decreased shoot and root K/Na and Ca/Na ratios, however, application of 10 mg zinc kg-1 soil significantly increased shoot Ca/Na ratio and had no significant effect on K/Na ratio.