Cheese or cheese infusions - Ecological traps for mosquitoes and spotted wing Drosophila
We tested the hypothesis that the "ecological trap" phenomenon (a mismatch between a habitats perceived attractiveness and its actual quality, resulting in a population sink) is exploitable for pest control. We selected mosquitoes as modal organisms, because selection of an oviposition site by adult female mosquitoes in response to its perceived attractiveness is of paramount importance for the development and survival of their larval offspring. In laboratory and/or field experiments, we show that (i) each of five cheese varieties tested (Raclette, Pecorino, Brie, Gruyere, Limburger) strongly attracts females of both the yellow fever mosquito, Aedes aegypti, and the common house mosquito, Cx. pipiens; (ii) cheese infusions, or headspace odorant extracts (HOEs) of cheese infusions, significantly affect oviposition choices by Cx. pipiens and Ae. aegypti, (iii) HOEs contain at least 13 odorants; (iv) in field settings, cheese infusions more effectively stimulate oviposition by Cx. pipiens and Culiseta incidens than bluegrass (Poa sp.) infusions, and also capture (by drowning) the spotted wing Drosophila (SWD); (v) the microbe composition of home-made cheese infusions modulates oviposition choices by mosquitoes; and (vi) the type of cheese infusion coupled with its nutritional content strongly affects the survivorship of mosquito larvae. In combination, our data show that microbial metabolites associated with cheese and cheese infusions are both attractive to adult mosquitoes seeking hosts and oviposition sites, respectively, and are toxic to mosquito larvae. These microbes and their metabolites could thus be coopted for both the attract and the kill function of "attract & kill" mosquito control tactics. Implementation of customizable and non-conventional nutritional media, such as home-made cheese infusions, as microbe-based ecological traps presents a promising concept which exploits insect ecology for insect control.