The project combined theory and state-of-the-art methods from ecophysiology, ecotoxicology, immunology, evolutionary ecology and molecular biology. In the study of thermal stress exposure, the fellow and her co-authors modified a specific device to measure both Ctmin and Ctmax (minimum and maximum critical thermal limits). Factors affecting the plastic Ctmax and mechanisms underlying the variation of the Ctmax of insects is a very topical issue in a changing climate. Measuring CTmax is relevant method because it is relatively fast, it yields parametric numbers that can be compared reasonably easily and it is intuitively related to obvious heatwave effects of climate change and distribution limits. The fellow and her collaborators used molecular methods such as DNA and RNA extraction, and amplicon sequencing (16S rRNA genes) using the unique barcodes and amplification procedure to study among-species differences in microbiota. In recent years, particular interest has focused on the importance of microbiome for immunity and other body functions as well as on the patterns of among-species variation in the microbiota. The fellow and her co-authors conducted the first comparable, phylogenetic study on the effects of a neonicotinoid pesticide, thiacloprid. Thiacloprid is a less-studied, but commonly used pesticide in Europe. At the moment thiacloprid is a “candidate for substitution” in EU due to its endocrine disrupting properties and possible detrimental effects on pollinators. The fellow also combined methods from thermal biology, microbiology and ecotoxicology by studying the single and multiple effects of the three important stressors (temperature stress, bacterial exposure and thiacloprid exposure). Prior to this project these interactions had not been well-explored for two stressors. Moreover, the effects of the three-stressor combination on insects had never been comprehensively investigated, even though these kinds of three-way interactions are very realistic in nature conditions. The research has many novel prospects and provides new understanding of effects of the chosen stressors both when applied in isolation and simultaneously. The project has applications in environmental management and protection. For example, interactions between environmental chemical stress and other stressors may lead to much greater / smaller sub-lethal effects (mechanistic cross-tolerance) than are presently explored when assessing safety of chemical compounds. Finally, this project yielded new information on the stress tolerance of the spotted wing Drosophila which is a highly invasive and economically important pest of various soft fruit and berries in Europe and North America.
