A research on the chemical control of hazelnut cone mites [Phytoptus avellanae Nalepa (Acarina: Phytoptidae) Cecidophyopsis vermiformis (Nal.) (Acarina: Eriophidae)]

This study titled "A research on chemical control of hazelnut cone mites [Phytoptus avellanae (Nal.) (Acarina: Phytoptidae) Cecidophyopsis vermiformis (Nal.) (Acarina: Eriophyidae)]" was created using qualitative and quantitative research methods. Our country has approximately 75% of the world's hazelnut production areas and an average of 62% of its production. In addition to being one of the most important industrial agricultural products of Turkey, hazelnut has become an important source of income in the regions where it is produced. As with every plant, mites are also harmful on hazelnut trees, one of the important fruit species of our country. Hazelnut cone mites enter the fruit shoot buds of hazelnuts and inflate them into a gall shape. Today, a single application is recommended for chemical control against hazelnut cone mites. Even in new licensing studies against these pests, biological activity studies are carried out similarly through a single application. This thesis study was carried out to examine the effect of different sprayings on hazelnut cone mites on the pest population and to see the relationship between the number of pesticides and effectiveness. The study was carried out in Bafra district of Samsun province, and the garden that was harmful to the application density was determined by conducting a survey study before the study and it was selected as the application garden. The necessary counting and labeling were made and the pesticide applications were made according to the determined calendar. Cone counts were made in the fall and spring periods after the application of pesticides. According to the data obtained, 2.59% less cones were detected in the plot with two sprayings compared to the plot with single spraying in the fall census. On the other hand, in the parcel with three sprayings, 14.05% less cones were detected compared to the parcel with one spraying, 11.46% less than the parcel with two sprayings. In the spring census, 4.53% less cones were detected in the parcel with two sprayings compared to the parcel with one spraying. In the plot with three sprayings, 16.99% less cones were detected than in the plot with one spraying, 12.46 percent less than the plot with two sprayings. When the results are evaluated in terms of average effect, the highest effect in the autumn census is 75.73%, in the plot with three sprayings, in the spring. In the census, it was obtained with 74.14% in the parcel where three applications were made.