The role of microbiome in host plant colonization and foraging of fly pests

Invasive flies are global threats to food security and the economy as they can destroy crops and inflict multi-billion dollar losses to crop production. Among the most destructive is Drosophila suzukii, a pest of soft-skinned fruit crops that is broadly established in the US, Canada, South America, and Europe in the past 10 years. Despite decades of research and pest management on D. suzukii, current controls rely almost exclusively on chemical insecticides, which are not effective against larvae feeding inside fruits and are not sustainable. Robust trapping systems to optimize D. suzukii monitoring and environmental-friendly approaches such as autocidal programs (e.g. sterile insect techniques) are urgently needed for D. suzukii management. 
On the basis of our ten years of research on Drosophila melanogaster, a species closely related to D. suzukii, we have demonstrated that the fly microbiome accelerates larval development, affects host foraging behavior, and increases reproduction, all important parameters of fly invasiveness. For D. suzukii, there remains a lack of knowledge explaining how they are able to colonize and develop so rapidly on many different host plants. The critical question is how the interactions among the community of gut microbes (the microbiome) and SWD facilitate colonization of host plants, thus establishment of invasive pests in new areas. 
We are currently conducting transcriptomics analysis of the D. suzukii microbiome across different host fruits, and identifying microbiome-derived volatiles that facilitate D. suzukii attraction to fruits. Our long-term goal is to leverage the knowledge of fly-microbe interactions to develop effective and sustainable strategies to manage invasive fly pests.