Determination of DRIS Norms and Nutrients Deficiency Diagnosis in Owhadi Cultivar of Pistachio (Pistacia vera L.) Trees

Nutrients have a great effect on quantity and quality of pistachio. Considering that Diagnosis and Recommendation Integrated System (DRIS) uses the nutritional balancing concept or relationship among nutrients, usage for the over growth stage and equal effect in different varieties and climates, it is postulated that this method might be more precise than other methods in the detection of nutritional deficiencies or/and excesses in pistachio trees. More than 3000 leave samples from different orchards in pistachio growing area of Kerman province were selected to determining of DRIS norms. Ten nutrients were determined in the samples which were collected from non-fruit branches in July, including of nitrogen(N), phosphorous(P), potassium(K), calcium(Ca), magnesium(Mg), iron(Fe), zinc(Zn), manganese(Mn), copper(Cu) and boron(B)  according to the conventional methods. DRIS norms were determined by selected nutritional rates based on greatest variance ratio of high-yielding and low-yielding population with 2000Kg/ha as discriminating border for low and high-yielding population. DRIS indexes were presented based on determined DRIS norms. These indexes can be defining priority of nutrients deficiency in pistachio leaf. Priority of ten nutrients was determined for each pistachio orchard with low yield and as totally nutrients requirement arrangement was as Mn>Zn>K>Fe>N>Cu>P>Ca>B>Mg in pistachio growing area of Kerman province. More pistachio orchards in this study had manganese, zinc, potassium, iron and nitrogen deficiency. High NBI in low-yielding population indicate unbalancing nutrients in study areas.