Speaker
Description
The Eurasian spruce bark beetle (Ips typographus) is currently the most economically relevant pest of Norway spruce (Picea abies). This insect associates with filamentous fungi that may help it overcome the tree’s chemical defenses. However, the involvement of other microbial partners in this pest’s ecological success is unclear. In past works, we have shown that the core fungal and bacterial gut microbiota is stable across life stages, geographic location, seasonality, and rearing conditions. Further, we have shown that I. typographus females transfer part of its microbiota to the eggs via the deposition of an bark plug treated with maternal secretions, and by inducing an increase in abundance of a subset of taxa from the adjacent phloem. While the taxanomic characterization transmission routes of the core taxa are important groundwork to understand the importance of the microbiota for the host, the location of the bacterial partners in the gut has remained elusive. The use of advanced microscopy techniques, such as Fluorescence Lifetime Imaging (FLIM) and Stimulated-Emission Depletion (STED), could be the key to overcome the difficulties of imaging symbionts in the gut of bark-feeding insects. Imaging the distribution of key microbial taxa along the alimentary canal would provide valuable information to understand this complex microorganism-plant-arthropod study system.
