The Leafhopper Fauna of an Apricot Orchard in Hungary

European stone fruit yellows (ESFY) is widespread in Europe. The disease, which is on the increase in Hungary, causes losses in yield, deterioration in fruit quality, decrease in the lifespan of fruit bearing trees and finally the death of the plant affected. It is most probably the leafhoppers and psyllids that play a role in the spread of the disease. In Hungary, the species composition of leafhoppers in apricot orchards had not been known before our research was carried out. In order to search for the potential vectors of the disease, research was undertaken to identify the leafhopper species present in the orchard along with their population changes. Samplings and checks were taken periodically in a pesticide-treated apricot orchard infected with ESFY in Pomáz, during the whole vegetation period of 2001. Various collecting methods were used for monitoring the species. Samples were obtained from the canopy, the undergrowth and the plants adjacent to the orchard by the means of Malaise traps, suction traps and yellow sticky boards. 3117 individuals belonging to 85 leafhopper species were collected during our samplings. A species (Edwardsiana sp.) presumably new to the fauna was also collected, although research is still underway to remove all doubts about its identification. The leafhoppers were present throughout the vegetation period. A significant increase in the number of Edwardsiana lamellaris, E. rosae and of Eupteryx calcarata was detected between the end of May and the beginning of June, whereas in the middle of August, at the end of September and in mid-October an increase in the number of Empoasca solani, E. decipiens and Zygina flammigera was observed. On the basis of the abundance of the species as well as that of the study of the canopy it can be stated that apricot trees are among the host-plants of Edwardsiana lamellaris, E. rosae and Eupteryx calcarata. Our objectives for further studies are to assess the role in ESFY transmission of the leafhopper species collected.