Effect of different zinc application methods on leaf Zn, Fe, Cu and Mn concentrations of ungrafted and grafted Flame Seedless grapevine cultivar and rootstocks (Vitis sp.)

A two-year vineyard experiment was conducted to investigate the effects of zinc applications on leaf Zn, Fe, Cu and Mn concentrations of ungrafted and grafted grapevines ‘Flame Seedless’ (V. vinifera L.) cultivar and the rootstocks 5 BB (V. berlandieri x V. riparia), SO4 (V. berlandieri x V. riparia), Cosmo 20 (V. berlandieri x V. riparia), Fercal ((V. berlandieri x Cabernet Sauvignon) x (V. berlandieri x Colombard)), Dogridge (V. champinii), Harmony (Dogridge x 1613 C), 1613 C (V. solonis x V. othello). Zinc applications were performed as l) Zn = 0 (0 kg ha -1 as control), 2) soil application (23 kg ha -1 ), and 3) soil (23 kg ha -1 ) plus leaf (0.2% Zn) applications of Zn. As Zn source, ZnSO 4 .7H 2 O formulation was used. Leaf samples were gathered at full blossom and veraison stage in order to determine Zn, Fe, Cu and Mn concentrations. The results showed that Zn applications had significant influence on the Zn, Fe, Cu and Mn levels of grapevine genotypes. Soil plus leaf application of Zn resulted in the highest Zn, Fe, Cu and Mn concentrations of leaves. A wide variation was determined among the genotypes in terms of microelement uptake. Leaf Zn, Fe, Cu and Mn concentrations were higher in the own-rooted Flame Seedless than those of the vines of the same cultivar grafted on different rootstocks.