Mineral Nutrients have a great effect on quantity and quality of pistachio. Since micro-nutrient fertilizers are not regulary used, imbalance condition may occur. It is probably the main reason for the decreasing of yield. The average of yield in Iran is about 1200 Kg/ha(about 1/5 of the potential yield). The advantages of Diagnosis and Recommendation Integerated System are: 1) consideration of nutrients balance situations, 2) usage for the over growth stage, and 3) equal effect in different varieties and climates, with regard to these advantages, the DRIS method has been used. The following elements have been analysed: N, P, K, Ca, Mg, Fe, Mn, Cu and Zn for the leaf samples from 200 different orchards. The elements were analysed according to the conventional methods. The selected norms were chosen with regard to the t-test and variance ratio of high-yielding and low-yielding population (variation was over and less than 4 Kg/tree). These norms were calculated by means of expression forms in high-yielding population along with their CV. The employed methods for calculating DRIS indexes are: 1) DRIS, 2) M-DRIS, 3) DRIS through range norms and 4) M-DRIS through range norms. Using of confinement range norms decreased Nutrient Balance Index (NBI). According to the results, the calculated norms, along with M-DRIS through range norms(±8/3 SD) method, can be used for deficiency diagnosis and fertilizer recommendation in pistachio trees.
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