The effects of certain applications on fruit quality, periodicity, and nutrient uptake in pistachio (pistacia vera L. CV. Siirt)

In this study, the effects of salicylic acid (SA) and compound foliar fertilizer (FF) applications on the nutrient elements, physiological status, and overall development of pistachio plants in a full-yielding orchard located in the central district of Siirt province were evaluated. The applications were performed via foliar spraying, and four treatment groups were tested: control, SA only, FF only, and the SA+FF combination. The findings indicate that both treatments improved the nutritional profile of the plants, particularly by influencing the uptake of macro- and micronutrients. The highest shoot length was recorded in the SA treatment at 22,28 cm, while the SA+FF combination resulted in the lowest value at 21,06 cm. SA application produced a significant increase compared to the control, whereas FF showed a moderate effect. Observed increases in proline, antioxidant enzyme activities, and the accumulation of micronutrients such as potassium, zinc, and iron suggest that the treatments positively modulated the plant's metabolic and stress responses. Moreover, the SA+FF application was found to enhance nutrient uptake in pistachio plants under drought conditions, thereby strengthening their capacity to cope with drought stress. Keywords: Pistachio, Salicylic Acid, Compound Foliar Fertilizer, Fruit Quality, Number of Inflorescence Buds