|FAWAZ, EMADELDIN - Naval Medical Research Center|
|OBENAUER, PETER - Naval Medical Research Center|
|DICLARO II, JOSEPH - Naval Medical Research Center|
Submitted to: Journal of Vector Ecology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/15/2014
Publication Date: 12/1/2014
Citation: Fawaz, E.Y., Allen, G.M., Bernier, U.R., Obenauer, P.J., Diclaro Ii, J.W. 2014. Swarming mechanisms in the yellow fever mosquito: aggregation pheromones involved in the mating behavior of Aedes aegypti. Journal of Vector Ecology. 39(2):1-8.
Interpretive Summary: Scientists at the United States Department of Agriculture Center for Medical, Agricultural, and Veterinary Entomology and the United States Navy Medical Research Unit-3 and Navy Entomology Center of Excellence have studied the way that male and female mosquitoes locate each other. The studies showed that several similarly structured chemicals were detected and identified as being produced by mosquitoes. Laboratory tests showed that these chemicals produced a swarming behavior. Studies support the finding that female mosquitoes locate male mosquitoes partly by chemical cues. Future studies of these types of chemicals may lead to new forms of protection from mosquito bites. This work will ultimately increase our knowledge of how male and female mosquitoes locate each other, and this may lead to new ways to control mosquitoes which transmit diseases to humans and livestock.
Technical Abstract: Mosquitoes of various species mate in swarms comprised of tens to thousands flying males. Yet little information is known about mosquito swarming mechanism. Discovering chemical cues involved in mosquito biology leads to better adaptation of disease control interventions. In this study, we aimed at providing additional information on Aedes aegypti swarming behavior and identifying associated chemical cues. Novel evidence is provided that Ae. aegypti females aggregate by means of olfactory cues, i.e., aggregation pheromones. Isolation of Ae. aegypti aggregation pheromones were achieved by aeration of confined mosquitoes and collection of associated volatiles by glass filters. The collected volatiles were identified through Gas Chromatography Mass Spectrometry (GCMS). Three aggregation pheromones were collected and were identified as 2,6,6-trimethylcyclohex-2-ene-1,4-dione (ketoisophorone) (CAS# 1125-21-9, tR = 18.75), 2,2,6-trimethylcyclohexane-1,4-dione (the saturated analog of ketoisophorone) (CAS# 20547-99-3, tR = 20.05) and 1-(4-ethylphenyl) ethanone (CAS# 937-30-4, tR = 24.22). Our biological studies revealed that the identified compounds stimulated mosquito behavior under laboratory conditions. The mechanism of mosquito swarm formation was discussed in light of our behavioral study findings. A preliminary field trial demonstrated the potential application of the isolated aggregation pheromones in controlling Ae. aegypti.