Interactive effect of fungicides and insecticides on the gut microbiome composition and its implication to honey bee health
Apis mellifera has a relatively consistent gut microbial community that is thought to enhance host health and protect against parasites and pathogens. But the gut microbiome can be disrupted by pesticides and in-hive chemicals, putting honey bee health in danger. We used a controlled and fully crossed laboratory experimental design to test the effects of chronic exposure to field-realistic sublethal concentrations of two nicotinic acetylcholine receptor agonist insecticides (nACHRs) namely flupyradifurone (FPF) and sulfoxaflor (Sulf), and a fungicide, azoxystrobin (Azoxy), individually and in combination, on the survival of individual honey bee workers and their gut microbiota (fungal and bacterial diversity and composition).Our findings raise concerns about the long-term impact of the novel insecticides FPF and Sulf, particularly FPF, on pollinator health and recommend a novel methodology for a refined risk assessment that should include the potential effects of agrochemicals on the gut microbiome of bees.