A molecular gut content analysis reveals the feeding hosts of the Brown marmorated stink bug Halyomorpha halys

Abstract The Brown marmorated stink bug Halyomorpha halys is one of the most harmful invasive species worldwide. It is highly polyphagous with the ability to feed on more than 300 different plants. So far, most studies describe the different host plants based on visual observations, which allowed to diagnose the most important host plants in the invasive range in North America and Europe. However, the exact feeding behavior of this important pest species is not known. By applying a molecular gut content analysis approach to individuals collected in the field across the seasons, we investigated the feeding plants and the composition of plants which were ingested on an individual level. In total, we detected 65 different feeding host genera belonging to 37 families, with Salix, Robinia, and Malus being the most important genera. Moreover, we newly described eight plant genera as host plants of H. halys. The number of plant genera within single individuals ranged from one up to 17, highlighting a complex feeding behavior and supporting the highly polyphagous nature of this species. Beta diversity analysis of host plants over the seasons showed significant differences and highlights different feeding hosts in winter and summer months and overall a different range of host plants across the season. Our results provide new insights into the feeding behavior of H. halys and provide important knowledge about the biology of this important pest species.