Electroantennogram and Behavioral Responses of Culex quinquefasciatus (Diptera: Culicidae) Females to Chemicals Found in Human Skin Emanations

Abstract

The southern house mosquito, Culex quinquefasciatus Say (Diptera: Culicidae), is closely associated with humans and is a vector of Þlariasis. Use of semiochemicals for control of mosquitoes is a novel and potentially ecofriendly control approach. Human skin emanations are known to attract mosquitoes. In the current study, olfactory and behavioral responses of host-seeking female Cx. quinquefasciatus to various chemical components of human skin emanations (carboxylic acids, alcohols, and aldehydes) were evaluated separately at three doses (0.01, 0.1, and 1 g) for electroan-tennogram (EAG) and three doses (0.1, 1, and 10 g) for behavioral assay. Results of EAG studies indicated that all carboxylic acids elicited signiÞcant olfactory responses except tetradecanoic acid (C 14) and octadecanoic acid (C 18). In particular, hexanoic acid (C 6) elicited a maximum, eight-fold olfactory response compared with the solvent control. Ethylene glycol and benzyl alcohol exhibited signiÞcant EAG and behavioral responses, whereas among aldehydes, nonanal elicited high EAG and behavioral responses, but only at all three doses tested compared with control. Some carboxylic acids elicited signiÞcant behavioral responses, attracting 75% of females tested toward chemical stimuli in a Y-tube olfactometer.