Host plant forensics and olfactory-based detection in Afro-tropical mosquito disease vectors

Author summary Plants play an important role in the fitness of mosquito disease vectors, yet the identity of plant species that they feed on in their natural habitats remains largely unknown. In this study, we employed DNA barcoding to identify the plant species fed upon by Aedes aegypti, Aedes mcintoshi, Aedes ochraceus and Anopheles gambiae in their natural habitats. Since plant feeding is mediated by olfactory cues, with potential application as attractant-based tools for vector surveillance, we identified specific odor signatures that may modulate host plant location. Our findings showed preference in odor detection among the vectors for different compound classes; benzenoids for Ae. aegypti, aldehydes for Ae. mcintoshi and sesquiterpenes and alkenes for An. gambiae. This study highlights the utility of molecular approaches in identifying specific vector-plant associations, a knowledge which can be exploited in maximizing vector control strategies such as attractive toxic sugar bait. Furthermore, the elucidation of potential odor signature lays foundation for development of plant odor-bait technology which is critical for surveillance of different mosquito disease vectors of varying physiological states and the pathogens they transmit.