Brown marmorated stink bug halyomorpha halys (stal) (hemiptera: pentatomidae) distribution and host plants in İstanbul province, Bosphorus districts Sariyer, Şile and Beykoz.

The brown marmorated stinkbug, Halyomorpha halys (Stål), is described as an invasive species native to East Asia. It was detected in Turkey for the first time in 2017 in Artvin and Istanbul, and has spread rapidly in the Black Sea region. While the studies carried out in the Black Sea region in recent years have allowed to follow a decisive path regarding the determination, spread and control of the pest, no such study has been pursued in Istanbul. This current study was performed in Sarıyer, Şile and Beykoz districts of Istanbul, due to having similar climate and vegetation characteristics with the Black Sea region. We selected different locations and areas in these three districts, placed traps in early april and monitored the pest weekly until the end of october. In this study we used pheromone traps to monitor the pest. When we compare these three districts where the research is carried out, Sarıyer has the highest population density and Şile has the lowest population. It was understood that the pest was seen in these three districts, but population had not yet reached the destructive density. The pest was first caught in the traps in May both in 2021 and 2022, while the highest number caught was reached in August in both years. Similar to the results of the previous studies carried out in the Black Sea Region, in this study we also found that the brown marmorated stink bug predominantly prefer hazelnut and apple. İn addition, the presence of the pest was detected in mixed fruit orchards and mixed vegetable gardens. Studies carried out through these two years to determine host preference in vegetable gardens, however, showed that the bug didn't invade vegetable in greenhouses. When we evaluate damage of H. halys in the countries in which the bug spread and Turkey, it is known that this pest causes serious economical loss. For this reason; In order to prevent its spread and its effective control, it is important to start studies on the parasitoid Trissolcus japonicus, one of the most effective biological control agents successfully used in the USA and European, immediately. Keywords: Halyomorpha halys, Brown marmorated stinkbug, İstanbul, Host plant, Spread