U.S. Department of Agriculture: Agricultural Research Service, Lincoln, Nebraska


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INSECT REPELLENTS: PRINCIPLES, METHODS, AND USES, ed. Mustapha Debboun, Stephen Frances, & Daniel Strickman (CRC Press, 2006)


One mechanism by which the action of semiochemicals can be classified is based on the behavioral impact within or external to the species of interest. As such, one can classify a chemical as one of the following2,3:

1. Pheromone, if it results in response between insects of the same species
2. Kairomone, if it results in response in another species that benefits the species receiving the chemical cue
3. Allomone, if it results in response in another species that benefits the species releasing the chemical cue

However, the distinctions can be more specific by classification of chemical cues through the imparted behavioral effect: attractant; repellent; arrestant; locomotory stimulant; feeding, mating, or oviposition stimulant; and feeding, mating, or oviposition deterrent.2,4 Karlson and Lu¨ scher first proposed the term “pheromone” to describe chemicals with instraspecific species activity.5,6 Chemicals with interspecific species activity are allelochemicals.3 Allelochemicals can be separated further into kairomones, of which attractants are a category of, and allomones, which are the primary focus of both this book and chapter, and the class that repellents are a part of. Furthermore, attraction-inhibitors, are classified by us as a category of repellents. Ironically, many of the attraction-inhibitors have been discovered in a search for kairomones used by mosquitoes to locate human hosts. Attraction-inhibitors may not repel by the traditional mechanisms, but they do interfere, or act as an antagonist to the normal attraction response of an insect to attractive odor(s).

The proper name for the behavioral actions that are described in this chapter can be debated extensively and additional discussion of terminology is found in Chapter 2 by White. In this short prequel to the main body of our contribution on human and other compounds that interfere with mosquito host-finding, we put forth our rationale supporting the terms used to describe behaviors reported in this chapter.