Effect of Pollination Time on Yield and Antioxidant Properties of Some Pistachio Cultivars

To obtain the best quality and quantity of pistachio fruits, knowing the most suitable time of pollination, is of paramount importance. This study was conducted to investigate the effect of pollination time, different stages of female flower development, including A (lower florets opened and clusters were green), B (lower and medial florets opened and clusters were green), C (all florets opened and clusters were light green), D (the stigma in the lowest florets was light pink), and E (the stigma in the lowest and medial florets was pink) on quantitative and qualitative characteristics of fruits in three pistachio cultivars (‘Ghermez Peste’, ‘Kal Khandan’, and ‘Kaleh Bozi’). Results showed that the highest yield in ‘GhermezPeste’ obtained when the manual pollination carried out at the stage that the cluster were green (early flowering period) while the highest yield In ‘KalKhandan’ and ‘KalehBozi’ were observed when the pollination carried out at the full bloom stage. The highest amount of total phenolics, total flavonoid, and antioxidant activity of fruits observed when pollination carried out at the stage that lower florets opened and clusters were green. The Lowest amount of total flavonoid and antioxidant capacity were obtained in the fruits that pollination carried out in the stage that the stigma in middle and lower florets were pink. As a first step towards identifying the best time for manual pollination of pistachio trees, our results showed manual pollination in the suitable blooming stage led to higher yield and quality of pistachio nuts.