First evidence of the brown marmorated stink bug and its population size in perennial crops in Croatia

The brown marmorated stink bug, Halyomorpha halys Stal, is an invasive Pentatomidae species that causes damage to economically important agricultural crops. It originated in East Asia but has successfully spread to many European countries. It has been present in Croatia since 2017, and its first mass emergence was detected in a soybean field in 2019. Therefore, the aim of this study was to determine the occurrence and population size of H. halys in perennial crops in important fruit growing areas in Croatia. According to the monitoring data, H. halys was detected in all surveyed areas and crops (apple, apricot, cherry, fig, grapevine, pear, plum, olive, and hazelnut). The largest population size was detected for hazelnut in the locality of Tovarnik, Vukovar-Syrmia County (79 individuals), for pear in the locality of Marijanci, OsjekBaranja County (31 individuals), and for apple in the locality of Staro Cite, Zagreb County (25 individuals). In view of the fact that the weekly catches at some monitoring sites exceeded the established treatment threshold, control measures must be taken to prevent an increase in the population and significant damage in the future. In addition to hazelnuts, crops such as pears, apples and cherries are particularly threatened by this pest.