Effects of Leaf Position on Blade and Petiole Mineral Nutrient Concentration of Tempranillo Grapevine ( Vitis vinifera L.)

Concentrations of N, P, K, Ca, Mg, Fe, Mn, Zn, Cu, and B were monitored throughout the season in leaf blades and petioles sampled at three different positions on the shoot of Tempranillo ( Vitis vinifera L.) grapevines. Petioles had higher concentrations of K, Mg, and Zn, whereas N, P, Ca, and micronutrients other than Zn were more abundant in leaf blades. Seasonal trends were identified for macronutrients, with decreasing patterns for N, P, and K, while Ca and Mg increased through the season. Minor differences in nutrient concentration were observed in leaf blades and petioles opposite basal and distal clusters. These results provide guidelines for the sampling of representative tissues for nutritional diagnosis of Tempranillo after veraison. However, differences among leaves opposite basal clusters and those placed four nodes beyond the second cluster suggest that these younger leaves are not useful for nutritional diagnosis using reference concentrations obtained for basal leaves.