Submitted to: Biocontrol
Publication Type: Peer reviewed journal
Publication Acceptance Date: 3/17/2010
Publication Date: 4/9/2010
Citation: Joyce, A.L., Aluja, M., Sivinski, J.M., Vinson, B., Ramirez-Romero, R., Bernal, J.S., Guillen, L. 2010. Effect of continuous rearing on courtship acoustics of five braconid parasitoids, candidates for augmentative biological control of Anastrepha species. Biocontrol. 55:573-582. Interpretive Summary: Parasitoids of pest fruit flies are sometimes mass-reared and released in large numbers to suppress pest populations. Such rearing may result in inadvertent “domestication” and a decline in the quality of the insects. Scientists at the ARS Center for Medical, Agricultural and Veterinary Entomology in Gainesville, Florida collaborated with colleagues from Texas A&M University and the Instituto de Ecologia, Xalapa, Veracruz, Mexico, to develop a method of examining changes in parasitoid behavior over many generations in the factory. They used the sounds male wasps make as they court females since these are likely to be displays of vigor and reflect insect health. In general they found few differences between relatively wild and long-domesticated specimens. This suggests that the techniques used for production result in a quality product.
Technical Abstract: The courtship acoustics of five species of parasitoid wasps (Hymenoptera: Braconidae), potential candidates for augmentative biological control of Anastrepha species (Diptera: Tephritidae), were compared between recently colonized individuals and those continuously reared 70-148 generations. During courtship, males of these parasitoid species fan their wings and produce a low amplitude sound. Airborne courtship sounds were recorded from young and old colonies using a microphone. The first series of 15 continuous courtship pulses was used to measure pulse duration (ms), frequency (Hz), and interpulse interval (ms) from the beginning (B2), middle (M2), and end (E2) of the pulse series. These courtship acoustic parameters were also compared among species. Several significant changes were detected in colonies that had been continuously reared. Pulse durations at L2 were longer for D. crawfordi, but shorter for D. longicaudata; interpulse intervals at M2 were shorter for O. hirtus, and at L2 were shorter for D. longicaudata and U. anastrephae. Comparisons among species found that the pulse duration at M2 distinguished all three native species, and could also distinguish between the two introduced species. The current rearing environment of these parasitoids may help maintain their courtship acoustic behavior. We discuss our findings in light of their biological and applied implications, particularly those dealing with quality control of mass-reared parasitoids.