THE INVESTIGATION OF THE EFFECTS OF 17 FERTILIZERS TREATMENTS IN THE FORM OF FOLIAR APPLICATION ON QUALITATIVE CHARACTERISTICS OF PISTACHIO NUT CULTIVAR 'OUHADI'

Regarding the presence of calcareous soils with high pH and EC in pistachio production areas in Iran, mineral nutrient absorption by plants becomes difficult and consequently nutrient deficiency is common. In order to increase the efficiency of chemical fertilizers in arid areas, and increase the quantity, quality and biological value of yield, foliar application of chemical fertilizers is the priority. Thus, in the present experiment, complete fertilizer, potassium, calcium, iron and copper in different concentrations and combinations were used to investigate their effects on pistachio fruit quality. Mean comparison of data showed that percentage of small, semi kernel, blank and none splitting fruits, and pistachios/ounce was improved by all foliar applications of fertilizer. The lowest percent of small nut and blank nut was observed in calcium and commercial complete micro-nutrient solution (2 g L-1) and iron and copper (1 g L-1) treatments respectively. Pistachio fruits/ounce was improved by iron and copper treatments. Thus, it is concluded that foliar application of fertilizers increase fruit quality in pistachio trees ‘Ouhadi’.