The effect of acaricides on some bacteria species live in the honey bee gastrointestinal system

Varroa mite continues to inflict substantial economic losses in the global beekeeping sector. In colonies, the use of synthetic acaricides is one of the strategies explored in the combat against mites. The microbiota of honeybees have a crucial role in pathogen protection, metabolism, efficiency, development of the immune system, body, and behavior. In this dissertation, the genetic identification of bacterial species isolated from the digestive tract of honey bees and the antibacterial activity of acaricides were examined using the disc diffusion method. The antibacterial activity of 1/1, 1/2, 1/4, 1/8, 1/16, and 1/32 dosages of acaricides including amitraz, flumethrin, and tau-fluvalinate was statistically tested for this purpose. There were three replications of the experiments. On Lactiplantibacillus spp., the inhibition zone diameter of Amitraz was 14.96 mm, 14.43 mm, 13.56 mm, 11.46 mm, 10.13 mm, and 7.66 mm, respectively. On Leuconostoc mesenteroides, inhibition zone sizes of 17.83 mm, 16.56 mm, 12.93 mm, and 8.70 mm were generated, respectively. On Bifidobacterium spp., the inhibition zone diameters were 15.36 mm, 14.43 mm, 13.50 mm, 12.26 mm, and 10.23 mm, respectively. Klebsiella aerogenes and Citrobacter freundii exhibited no antibacterial action against amitraz. Flumethrin and tau-fluvalinate-containing acaricides exhibited no antibacterial action against all tested microorganisms. In this research, it was discovered that acaricides containing amitraz had an antibacterial impact on some lactic acid bacteria in the honeybee digestive system. Future research must explore the impact of acaricides used against varroa mite in beekeeping on the honeybee microbiome in more detail and offer information on the creation of new strategies to combat the increasing negative effects. Keywords: Honey bees, varroa, bacteria, amitraz, flumethrin, tau-fluvalinate, disc diffusion