Ionome composition and interactions in ‘Golden Delicious’ apple trees on calcareous soils

Balanced nutrition ionome composition and interactions, especially under environmental stress, have a great effect on improving the performance of ‘Golden Delicious’ apple orchards. Under such conditions, establishing the local compositional nutrient diagnosis standards is essential for determining the nutritional balance in apple orchards. Only well-documented data sets can fully capture the combined effects of yield-driving variables at local scale and can be used to adjust fertilization in the same conditions. For this purpose, the leaf nutrient concentrations and yields of 81 commercial orchards were determined. The local nutrient reference norms were calculated by the compositional nutrient diagnosis (CND) method. According to principal component analysis (PCA), the priority for increasing the yield in the low-yielding subpopulation of commercial ‘Golden Delicious’ apple orchards, grown on alkaline soil with high pH conditions, is the leaf Ca, B, S, Mg, K, Zn, Fe and Cu concentration, respectively. By using the CND norms obtained in calcareous soil conditions and reducing the nutrient imbalance index (CNDr²), it is possible to significantly increase the productivity of ‘Golden Delicious’ apple orchards under the same condition.