Effects of Organic Amendments on Microbiota Associated with theCulex nigripalpusMosquito Vector of the Saint Louis Encephalitis and West Nile Viruses.
Pollution from nutrients in aquatic habitats has been linked to increases in disease vectors, including mosquitoes and other pestiferous insects. One possibility is that changes in mosquito microbiomes are impacted by nutrient enrichments and that these changes affect various traits, including larval development, susceptibility to larval control agents, and susceptibility of the adult mosquitoes to pathogens. We tested this hypothesis using field mesocosms supplemented with low- and high-organic-nutrient regimens and then sampled microbial communities associated with the naturally colonizingCulex nigripalpusmosquito vector. By high-throughput sequencing of 16S rRNA gene sequences, we found no significant differences in overall microbial communities associated with sampled mosquitoes, despite detecting discernible differences in environmental variables, including pH, dissolved oxygen, and nutrient amendments. Nevertheless, indicator species analysis revealed that members of theClostridialeswere significantly associated with mosquitoes that originated from high-nutrient enrichments. In contrast, members of theBurkholderialeswere associated with mosquitoes from the low-nutrient enrichment. High bacterial variability associated with the life stages of theC. nigripalpuswas largely unaffected by levels of nutrient enrichments that impacted larval microbial resources, including bacteria, ciliates, and flagellates in the larval environments.IMPORTANCEMosquito microbiota provide important physiological and ecological attributes to mosquitoes, including an impact on their susceptibility to pathogens, fitness, and sensitivity to mosquito control agents.Culex nigripalpusmosquito populations transmit various pathogens, including the Saint Louis and West Nile viruses, and proliferate in nutrient-rich environments, such as in wastewater treatment wetlands. Our study examined whether increases in nutrients within larval mosquito developmental habitats impact microbial communities associated withC. nigripalpusmosquitoes. We characterized the effects of organic enrichments on microbiomes associated withC. nigripalpusmosquitoes and identified potential bacterial microbiota that will be further investigated for whether they alter mosquito life history traits and for their potential role in the development of microbial-based control strategies.
Florida Medical Entomology Laboratory, IFAS, University of Florida, Vero Beach, Florida, USA.
Dagne
D
Duguma
Faculty of Computer Science, Dalhousie University, Halifax, Nova Scotia, Canada.
Michael W
MW
Hall
Florida Medical Entomology Laboratory, IFAS, University of Florida, Vero Beach, Florida, USA.
Chelsea T
CT
Smartt
Department of Biology, University of Waterloo, Waterloo, Ontario, Canada.
Josh D
0000-0002-8722-8571
JD
Neufeld
aquatic chemistry; bacteria; disease vectors; food web; life stages; microbiome; mosquito; pollution