ABSTRACT
This chapter discusses natural molecules which function as repellents to insects. The intended purpose is to provide a highly representative, if not exhaustive, exposure to repellents. If people consider all olfactory chemical communications in the whole of chemical ecology, most, if not all, volatile compounds are repellents to some species or biotypes, but also are attractants to others. Reagents may mimic actions at the behavioral, physiological, biochemical or biophysical level, or specifically probe energy transduction at the level of the redox chain, ATPase, or solute porter systems. Most insect-repellent phytochemicals are products of secondary metabolism. Both plants and animals have evolved chemically based defense systems against a spectrum of stressful agents in their environments. Specific binding sites for each ligand may easily exist, and the resultant interaction may cause characteristic energy changes in the exposed dendritic membrane. The energy transduction between repellents and dendritic membranes apparently involves biophysical principles which are common among the chemical senses.
