Effectivenes of pest management options for managments of brown marmorates stink bug Halyomorpha Halys (Hemiptera: Pentatomidae) in hazelnut orchids in the Republic of Georgia

Abstract

Distribution and management of Halyomorpha halys (Stål) in commercial hazelnut orchards were investigated during 2019 and 2020. Efficacies of management strategies including attract and kill strategy and border sprays were compared to grower’s standard management practices. Seasonality of H. halys were similar during both years with the first H. halys adults observed near the end of April and all instar nymphs being present from July 20 (820-900 DD13.9) to the end of September (1600-1655 DD13.9). Although no difference was detected between the treatment types before harvest, after harvest data suggest attract and kill strategy to be the most effective management program during both seasons. Evaluations of hazelnut quality demonstrated higher presence of healthy kernels in nuts collected from trees located in the interior of the block than on trees from the perimeter of the block. Corking damage was higher on nuts collected from trees near the edge of the orchard. Observed increase in corking damage of nuts on trees located inside of the block, was indirectly associated with the mid- and late season H. halys feeding in the interior of the orchard. H. halys management decisions in hazelnut orchards should be based on the documented presence of H. halys populations but growers should also factor in the potential influx of the pest from surrounding areas. In areas surrounded by wild vegetation use of insecticide treated nets as used in the attract & kill plots provides the most effective strategy in protecting nut crop.