OLFACTORY SENSITIVITY OF TSETSE TO PHENOLIC KAIROMONES

Behavioural and electrophysiological (EAG) studies were undertaken to determine the olfactory selectivity of the antennae of Glossina morsitans morsitans Westwood and Glossina pallidipes Austen to phenolic kairomones. Responses of both species to 3-alkylphenols increased as the alkyl chain increased from one carbon atom to three, while the opposite trend was observed with 4-alkylphenols. These results indicated that 4-cresol and 3-n-propylphenol are the most stimulatory of the two respective groups of phenols. However, comparison of the responses indicated differences in the sensitivities of the chemoreceptor systems of the two species. Hence different compositions of the phenols may be required to best attract these species. Probable interactions of the phenols with the binding sites on the receptor surface are discussed.