Interactions between leaf macro, micronutrients and soil properties in pistachio (Pistacia vera L.) orchards

The interactions between: (i) leaf dry matter macronutrients, micronutrients and soil chemical properties, (ii) leaf macro- and micronutrients, (iii) soil macro- and micronutrients and (iv) soil chemical properties, and soil micro- and macronutrients in 50 pistachio orchards were investigated in leaves and soils by means of regression analysis. Most of the soils were deficient in plant-available P, Zn, Mn, Fe, and B, while they were excessively supplied with Cu. Leaf analysis showed that most of the trees were sufficient in K, Mg, Mn and B, but deficient in N, P and Fe, and excessive in Zn and Cu. It was found that almost all the significant elemental interactions occurring in pistachio leaves or soils were synergistic, contributing considerable quantities of available nutrients and, therefore,improving the nutrient status of pistachio trees, and the level of soil fertility. On the otherhand, the interactions between K and Mg in leaves, and between soil pH and leaf N or soil Fe, Mn and B, were antagonistic. It is suggested that these results must be taken into account during fertilization of pistachio trees, in order to avoid nutritional disorders and to promote plant growth, productivity and nut quality