Comparative Responses of Anastrepha ludens and Anastrepha obliqua (Diptera: Tephritidae) to the Synthetic Attractant BioLure.

Abstract

The responses of wild and sterile Anastrepha ludens (Loew) and Anastrepha obliqua (Mcquart) fruit flies to the synthetic attractant BioLure were determined by electroantennography (EAG), in field cage tests using MultiLure traps, and by release-recapture field experiments using sterile flies. In EAG bioassays, no differences were found between species, sexes, sterile and wild flies. There were only specific differences and interactions in dose responses. More A. ludens than A. obliqua individuals were captured in multilure traps in field cage test. In A. ludens, there was not significant difference between the number of females and males captured, whereas in A. obliqua more females than males were caught. Age showed a bimodal response in both species and both sexes, with peaks at 4 and 14 d old. In the release-recapture experiments, there were significant differences between species, sexes, and orchards and among the days after release. More individuals of A. ludens than A obliqua were recaptured. Only in A. obliqua the difference between the sexes was significant, with a 3.60:1 female:male ratio. Orchard conditions affected the recapture rate, but in both orchards the largest number of flies recaptured occurred during the first day after release (46 and 88% in each orchard). Our results show that the response to this synthetic lure is species-specific and contribute to better interpret trapping data.