مشخصات پژوهش

The plum bud gall mite (PBGM), Acalitus phloeocoptes (Nalepa, 1890) (Acari: Eriophyidae), is one of the important pests of plums in West Azerbaijan Province, especially in Miandoab County. In recent years, special attention has been paid to the development of plum tree cultivation in this region. According to the statistics of the Agricultural Jihad Organization of West Azerbaijan Province (2020), the area under cultivation of plum orchards in this province was about 1326 hectares, from which 13,000 tons of crop were harvested annually. Therefore, studying the biology and distribution of this pest in the region is crucial for selecting the most effective control strategy for it in the area. Regarding the study of the relationship between the overwintering populations of PBGM and the cardinal directions, surveys were done in three orchards. Sampling of galls was carried out in mid-March 2025 on five randomly selected trees (marked with ribbon tapes) of four cultivars (Pofaki, Sharabi, Akhtari, and Santrizeh) in all three orchards. Four twigs per tree, each twig in one cardinal direction (North, South, East, and West), were cut and transferred to the laboratory for study. Therefore, 20 twigs were sampled for each cultivar in each orchard. Sampled twigs were approximately 30 cm long and had galls. Their galls were taken, and the total number of mites in galls of each twig was counted under a Nikon SMZ745 stereomicroscope at a magnification of 50x. Finally, a comparison between means for the total number of mites from the twigs of different cardinal directions was made using Minitab version. 17.3.1 Software. The results indicated a significant difference between them. The twigs of the East direction had significantly fewer mites (mean = 8259.8 ± 1423.2), while the other directions had more mites (mean > 10000). Further studies are needed to find the cause of these differences. We suggest conducting more detailed and extensive studies in this county to identify the facto