Response of Sultana vines (V. vinifera L.) on six rootstocks to NaCl salinity exposure and recovery

One-year-old Sultana (Vitis vinifera L.) vines, own-rooted and grafted on 41B, 110R, 140Ru, 1103P and SO4 were grown in sand–perlite mixture (1:1) irrigated with half-strength nutrient solution containing 5, 25, 50 and 100 mM of NaCl. Growth, tissue mineral content and leaf gas exchange response to salt treatment and subsequent recovery were examined over a 70-day period. Shoot growth, leaf area and total dry weight were significantly reduced (P<0.05) at all salinity levels. Tissue salt content increased significantly with increasing salinity, Cl− being always higher than Na+. Photosynthetic rate (Pn) and stomatal conductance (gs) were greatly reduced by salinity and highly correlated with leaf Cl− content. Own-rooted vines exhibited higher dry matter production and photosynthetic rates than grafted vines, despite the higher Cl− and Na+ content. During recovery, vines previously treated with 50 and 100 mM NaCl exhibited photosynthetic rates and stomatal conductances similar to the control, although laminae Na+ and Cl− content continued to increase. Our results showed that own-rooted ‘Sultana’ vines (V. vinifera) can cope better with high salinity followed by those grafted on 1103P, 140Ru, 110R, SO4 and 41B rootstocks.