Modeling the potential distribution of Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae) in western Oregon

The corn rootworm complex comprises three Diabrotica species (D. virgifera virgifera, D. undecimpunctata, and D. barberi), all detrimental pests of corn. In particular, D. virgifera virgifera, which is responsible for over one billion dollars in economic losses within the corn industry in the United States. In western Oregon, D. virgifera virgifera and D. undecimpunctata have established populations in vegetable crops. These pests are exposed to a broader range of host plants, food sources, and different environmental conditions compared to the Midwest.

To assess the potential range of suitable habitats for D. virgifera virgifera in western Oregon, we developed a correlative species distribution model. This modeling approach combines presence-absence data of D. virgifera virgifera with layers of environmental variables that influence the spatial distribution of this pest species. Presence-absence data of D. virgifera virgifera were collected from sweet corn, silage corn, and snap bean fields within the Willamette Valley region over the growing seasons of 2023 and 2024. This model provides a baseline tool for screening vulnerable areas that may require monitoring of D. virgifera virgifera and proactive implementation of integrated pest management (IPM) tactics. As the corn rootworm complex expands and establishes its populations in new regions, predictive tools are critical for mitigating their impact on diversified agricultural systems like those in western Oregon.