Updates on biological control of Asian longhorned beetle using parasitoids

The Asian longhorned beetle (ALB), Anoplophora glabripennis, is a high-risk invasive pest of hardwood trees. Native to China and the Korean peninsula, ALB has been detected since the late 1990s in the US and Canada and is targeted for eradication. Although invasive populations have been declared eradicated from Illinois, New Jersey and Ontario, they are still present in Massachusetts, Ohio and New York. Most recently (in 2020), an ALB infestation was detected in South Carolina. The economic, ecological and aesthetic impacts on the US would be devastating if the beetle continues to spread and become established in the US. The beetles can be difficult to detect, especially in large forested areas, and new introductions are an ongoing challenge. Considering the continuous threat of re-establishment in the US, sustainable management strategies such as biological control need to be developed for this invasive pest. Over the past several years, surveys for native ALB parasitoids have been conducted in China. A few parasitoid species have been discovered. Meanwhile, some native North American parasitoids have been evaluated for their potential to be used as novel-association biological control agents for ALB. Here, we provide updates on past efforts to collect and evaluate parasitoids for biological control of ALB and discus future direction toward the development of a biological control program for ALB by using parasitoids.