Population Density of the Common Pistachio Psylla, Agonoscena pistaciae, on Native and None-Native Pistachio Cultivars of Semnan Province

The common pistachio psylla, Agonoscena pistaciae Burckhardt & Lauterer (Hemiptera: Aphalaridae) is known as the key pest of pistachio trees in orchards of Semnan province, that annually caused considerable damage to pistachio yield and tree. The use of resistant cultivars is one of the methods of integrated pest management. Therefore, this research was carried out to determine and compare the population density of the common pistachio psylla on three native and two none native pistachio cultivars. For this purpose, psylla-infected orchards were selected in five pistachio plantation areas of Damghan. Samples were taken from each tree as a replication of 20 leaflets every 30 days. In the laboratory, the number of psylla eggs and nymphs on the leaflets was counted, and finally, by statistical analysis of the data, the contamination of each cultivar was determined. The results of this study showed that the population density of the common pistachio psylla in native and non-native cultivars of pistachio is statistically different. Among the cultivars tested, Akbari and Ahmadaghaii cultivars had the lowest population densities with averages of 11.48 ± 0.67 and 14.50 ± 0.73, respectively. The highest density of nymphs and eggs was observed on the Abbasali cultivar with an average of 52.06 ± 3.99 and 34.01 ± 5.46, respectively, which were significantly different from other cultivars. This information can be used in the integrated management of the common pistachio psylla.