Phytochemicals as population sampling lures.

Most mosquito species have 2 hosts: vertebrate animals and vascular plants. The kairomones of vertebrates have been employed extensively as attractants in traps that are used for surveillance, either to assess adult density of mosquito populations or to detect pathogen activity. They also have been employed in basic field studies of mosquito physiology, behavior, and ecology. The semiochemicals that mosquitoes use to find plant hosts for their sugar, by contrast, have not been utilized at all. Currently we are characterizing attractive blends of volatile compounds produced by plant species visited by Aedes vexans, Culex pipiens, and Anopheles gambiae. These blends may be effective in attracting a unique subset of a mosquito population when deployed in surveillance traps. The principal advantages of phytochemical attractants are that they lure a) both sexes, b) all ages, including those that are newly emerged, c) females in all gonotrophic states, and d) both nondiapausing and reproductively diapausing females. Potential challenges to their successful use are the abundance of competing volatiles, narrow plant-host specificity, and a weaker behavioral response to phytochemical cues.