Sexual communication and related behaviours in Tephritidae: current knowledge and potential applications for Integrated Pest Management

Tephritidae are an enormous threat to fruit and vegetable production throughout the world, causing both quantitative and qualitative losses. Investigating mating sequences could help to unravel mate choice dynamics, adding useful information to improve behaviour-based control strategies. We review current knowledge about sexual communication and related behaviours in Tephritidae, with a focus on six key agricultural pests: Anastrepha ludens, Bactrocera cucurbitae, Bactrocera dorsalis, Bactrocera oleae, Ceratitis capitata and Rhagoletis pomonella. We examine features and the role of male-male combat in lekking sites, cues affecting mating dynamics, and some fitness-promoting female behaviours that occur at oviposition sites [the use of oviposition marking pheromones (OMPs) and female-female fights for single oviposition sites]. We outline future perspectives and potential contributions of knowledge about sexual communication to Integrated Pest Management programs for tephritid pests. Sexually selected traits are frequently good indicators of male fitness and knowledge of sexual selection processes may contribute to the improvement of the sterile insect technique (SIT), to select genotypes with high reproductive success and to promote sexually selected phenotypes through mass-rearing optimization. Furthermore, males' exposure to parapheromones, such as phenyl propanoids (PPs), ginger root oil and trimedlure can enhance the mating success of sterile flies used in SIT programs. PPs are also a powerful tool to improve reduced-risk monitoring dispensers and the male annihilation technique, with low side effects on non-target insects. Lastly, we outline the possibility to sensitise or train mass-reared parasitoids on OMPs during the pre-release phase, in order to improve their post-release performance in the field.