EFFECTS OF SALINITY AND SOIL ZINC APPLICATION ON GROWTH AND CHEMICAL COMPOSITION OF PISTACHIO SEEDLINGS

The effects of four salinity levels [0, 1000, 2000, and 3000 mg sodium chloride (NaCl) kg-1 soil] and three zinc (Zn) levels [0, 5, and 10 mg kg-1 soil as zinc sulfate (ZnSO4.7 H2O)] on growth and chemical composition of pistachio seedlings (Pistacia vera L.) cv. 'Badami' were studied in a calcareous soil under greenhouse conditions in a completely randomized design with three replications. After 26 weeks, the dry weights of leaves, stems and roots were measured and the total leaf area determined. Salinity decreased leaf, stem, and root dry weights and leaf area, while this effect diminished with increasing Zn levels. Zn fertilization increased leaf, stem and root Zn concentrations, leaf potassium (K) concentration, and stem and root sodium (Na) concentrations, while decreased leaf Na concentration, and stem and root K concentrations. Salinity stress decreased leaf, stem, and root Zn concentrations, and leaf K concentration, while salinity increased leaf, stem and root Na concentrations, and stem and root K concentrations. Proline accumulation increased with increasing salinity levels, whereas the reverse trend was observed for reducing sugar contents. Zn application decreased proline concentration but increased reducing sugar contents. These changes might have alleviated the adverse effects of salinity stress.