Résumé
The role of olfaction in the host-oriented behaviour of tsetse is reviewed. For all tsetse, odours play a role in host location but the relative importance of olfactory stimuli varies between species. For Morsitans-group tsetse such as Glossina pallidipes and G. m. morsitans, host odours elicit long-range (similar to 100 m) orientation whereas Palpalis group species such as G. palpalis spp. and G. fuscipes spp., while showing significant olfactory responses, are much less responsive. Hence baiting traps with natural host odours can increase the catches of some Morsitans tsetse ten-fold compared to only a doubling with Palpalis tsetse. Species that are less sensitive to odours seem to be more responsive to visual stimuli. The semiochemicals present in host odour include carbon dioxide, 1-octen-3-ol, acetone, butanone, 4-methylphenol and 3-n-propylphenol. For Morsitans tsetse, odours from hosts are not, in general, significantly different from those of non-hosts and thus olfaction does not seem to play an important role in host selection. The notable exception to this is human odour which is repellent to some species of Morsitans tsetse. Traps and insecticide-treated targets baited with blends of 1-octen-3-ol, ketones and phenols are, arguably, the most successful application of artificial baits to vector control worldwide. The current use and future prospects of using natural and artificial baits to control tsetse are discussed.