Interactions of fungi and tree killing bark beetles: Geographic variation and interspecific competition

We have described in detail the complex interactions of Dendroctonus frontalis with its fungi. We also recently described the first occurrence of Dendroctonus mexicanus in the US. Nothing was known about the fungi associated with this insect. We isolated fungi from beetles collected in southern Mexico, southern Arizona and Mississippi. We identified individual isolates of fungi and compared their competitive abilities. We have identified new fungi associated with both of these tree killing bark beetles. While stain fungi appear to be less prevalent in association with D. mexicanus than with D. frontalis. Fungi associated with D. mexicanus are capable of effectively competing with D. frontalis associated fungi. Despite the close association between these beetles, there are significant differences in the composition and function of their fungal associates. Effective management will depend on accurate characterization of these closely related symbiotic systems.