Submitted to: Frontiers in Invertebrate Physiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 2/14/2013
Publication Date: 3/7/2013
Citation: Bohbot, J.D., Durand, N.F., Vinyard, B.T., Dickens, J.C. 2013. Functional development of the octenol response in aedes aegypti. Frontiers in Invertebrate Physiology. DOI: 10.3389/fphys.2013.00039. Interpretive Summary: Mosquitoes are attracted to their human or animal hosts in part by their odor. Among these attractive odors are carbon dioxide, lactic acid and octenol, an odor present in breath and sweat. Yet how the attractiveness of these chemicals vary with the condition of the mosquito is poorly understood. Here we show that while young female mosquitoes are capable of detecting an attractant (octenol), behavioral responses fail to occur until they are older. Moreover, mosquitoes may respond differently to combinations of attractants depending upon age. These results emphasize the importance of understanding elements of mosquito behavior in order to evaluate and maximize the effects of attractants and repellents in mosquito management. This knowledge may be used by entomologists and behavioral ecologists to target the sense of smell in mosquitoes for disruption of their behavior in order to protect humans and animals from these disease vectors.
Technical Abstract: Attraction of female Aedes aegypti mosquitoes to 1-octen-3-ol (octenol), CO2, lactic acid or ammonia emitted by vertebrate hosts is not only contingent on the presence of odorants in the environment, but is also influenced by the insect’s physiological state. For anautogenous mosquito species, like Ae. aegypti, newly emerged adult females neither respond to host odors nor engage in blood-feeding; the bases for these behaviors are poorly understood. Here we investigated detection of two components of an attractant blend emitted by vertebrate hosts, octenol and CO2, by female Ae. aegypti mosquitoes using electrophysiological, behavioral, and molecular approaches. An increase in sensitivity of octenol olfactory receptor neurons (ORNs) was correlated with an increase in octenol-mediated attractive behavior from day 1 to day 6 post emergence. While the sensitivity of octenol ORNs was maintained through day 10, behavioral responses to octenol decreased as did the ability of females to discriminate between octenol and octenol + CO2. Our results show differing age-related roles for the peripheral receptors for octenol and higher order neural processing in the behavior of female mosquitoes.