Meeting Abstract
During overwintering, ectotherms experience and respond to a range of environmental pressures; however, we know little of how biotic interactions influence overwintering success. Notably, the impact of the microbiome on host physiology is likely influenced by how overwintering stressors, such as low temperatures, change its composition and function. To understand the role of the microbiome in determining the success of overwintering insects, we began by exploring how overwintering affects the composition of the gut microbiome of the spring field cricket, Gryllus veletis. We exposed G. veletis to a simulated change in seasons that mimicked temperatures and photoperiods in London, Ontario, Canada, and identified the composition of the community of gut bacteria at time points corresponding to summer, autumn, early winter, mid-winter, late winter, and spring. We found that the composition of the gut microbiome is similar in summer and autumn and is dominated by the classes Bacteroidia and Clostridia. In winter, the composition shifts to favour Bacteroidia, suggesting that bacteria in the class Clostridia do not perform as well at low temperatures. In spring, the composition shifts once again as Gammaproteobacteria flourish. These changes in composition across season suggest that overwintering can markedly shift the microbiome into the growing season. These changes may influence how hosts respond to the multiple stressors associated with winter – from the response to cold stress to immune challenges – and it will next be important to determine how these shifts influence host success.
