Protecting American pine forests: Are unknown pathogens hiding in Asia?

Exotic beetle-fungus symbioses are causing increasing tree mortality in the United States. For example, the redbay ambrosia beetle (Xyleborus glabratus)carries a pathogenic fungus that is eradicating American Lauraceae and threatening the Florida avocado industry. The increasing number of exotic wood borers becoming established in the US makes it difficult for regulatory agencies to make decisions about which species are dangerous. This has led to a “wait-and-see” approach, which makes it nearly impossible to eradicate invasives once they have become established.

To determine if harmful invasions can be effectively predicted and prevented, symbiotic fungi of beetles in Asia were evaluated for pathogenicity to American trees. Beetles were collected in China and Thailand, where their symbiotic fungi were isolated from the beetles. Literature suggests these fungi could be pathogenic to pines (Pinus) in the southeast US. The fungal isolates, separated from their beetle vector, were tested for pathogenicity on the most economically and ecologically important pines in the southeast (loblolly, slash, longleaf) by inoculation in a quarantine facility. Data are being collected at the time of submitting this abstract. This project will test the feasibility of assessing the invasion potential of not-yet-established insects and fungi and will offer a route for regulatory agencies to effectively protect one of the most valuable commodities in the southeast: pines.