Effect of Rootstocks on Physiological and Biochemical Responses of Vitis vinifera ‘Shahroudi’ to Salinity and Bicarbonate Stress Conditions

The synchronization of salt stress and dominance of calcareous soils in warm and dry climate regions has led to alkaline salinity stress in vineyards. In this study, the effects of salinity and bicarbonate stresses (alone or in combination) on photosynthetic reactions and nutrient variations of Vitis vinifera ‘Shahroudi’ as a susceptible grape cultivar were evaluated. Using stenting method, scions of this cultivar were grafted on 140Ru, Asgari, and Yaghouti rootstocks. Ungrafted plants were also used to study the impact of rootstocks. Salinity stress which was applied at two levels of zero and 50 mM sodium chloride and bicarbonate stress at two levels of 0 and 5 mM potassium bicarbonate. Results of this study showed significant effect of these three factors (salinity, bicarbonate and rootstock) on catalase activity, transpiration rate, and specific leaf area. Salinity stress reduced total iron content by 36% and alkaline-salt stress decreased 25% of pure leaf photosynthesis. In saline and alkaline conditions, the highest amount of absorbed Cl- and Na+ was observed in Asgari (as compared to ungrafted plants). Results of this study confirmed differences between V. vinifera genotypes in response to salt and bicarbonate stress. Based on this study, Asgari rootstock could be recommended as a suitable rootstock for Vitis vinifera ‘Shahroudi’ in calcareous and saline soils.