ION AND MINERAL CONCENTRATIONS IN ROOTS AND LEAVES OF TWO GRAPEVINE CULTIVARS AS AFFECTED BY NITRIC OXIDE FOLIAR APPLICATION UNDER NACL STRESS

Aim: The present study was conducted to investigate the effects of SNP (sodium nitroprusside, as nitric oxide donor) on mineral concentration in two grapevine (Vitis vinifera L.) cultivars, Qarah Shani and Thompson Seedless, under different levels of NaCl stress. Methods and results: The plants were exposed to NaCl at the rate of 0, 25, 50, 75 and 100 mM in nutrient solution and foliar spray of SNP at 0, 0.5, 1 and 1.5 mM under an open hydroponic system. Results indicated that with increasing salinity levels, the Cl- and Na+ concentrations increased and the K+, Ca2+, Mg2+, NO3-N, Zn2+, Fe2+ concentrations and K+/Na+ ratio decreased in both cultivars. However, application of SNP mitigated the Cl- and Na+ concentrations and improved the K+, Ca2+, Mg2+, NO3-N concentrations in leaves and roots of both cultivars. The application of SNP did not significantly affect Zn2+ and Fe2+ concentrations under 100 mM NaCl. Conclusion: The adverse effects of NaCl stress in nutrient elements uptake were ameliorated by the exogenous application of SNP in grapevine. Significance and impact of the study: Salinity of soil and water sources is one of the most serious environmental threats in Iran. Iran ranks tenth among grape-producing countries in the world. Therefore, the application of SNP can serve as an important component to reduce the adverse effects of salinity stress in nutrient elements uptake in grapevine.