Submitted to: Florida Entomologist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: May 13, 2000
Publication Date: N/A
Interpretive Summary: Caribbean fruit flies are important pests on oranges, grapefruit, and other fruit with considerable export value. Methods are under development by scientists at the Center for Medical, Agricultural, and Veterinary Entomology in Gainesville, FL, to improve the ability to detect small infestations of fruit flies and control them without the use of pesticides. This report describes experiments studying how fruit flies are attracted to different combinations of pheromonal and acoustical stimuli known to be attractive in field trapping studies. The research improves our understanding of how these stimuli affect fruit fly mating behavior and may lead to development of improved trapping techniques.
Female Anastrepha suspensa (Loew) are attracted to traps baited with male pheromone and/or broadcast calling song, but a high variability in female responsiveness has hindered attempts to develop practical trapping systems. One factor that may contribute to response variability is prior experience with sexual signals. To investigate this effect, female responses to calling song were compared after 38-40-h pre-exposure to different combinations of males, females, male pheromone, and broadcast song. The song stimulus was standardized by concatenating copies of a 7.2-s recording from a sexually successful male, characterizing the song frequencies and temporal patterns using digital signal processing techniques. The standardized song contained wing-fanning pulse trains averaging 0.31-s in duration. Within the pulse trains, the frequency rose quickly from ~125 to 148 Hz and then slowly declined to ~120 Hz. Female responsiveness to this calling song did not exceed null levels unless the females were pre-exposed to males or male pheromone, although the responses after pre-exposure to calling song were significantly higher than the responses of unexposed females. The song was more attractive to females pre-exposed to males or male pheromone than to females kept in a clean wind tunnel or in a room only with females.