Comparison of laboratory and field bioassays of laboratory‐reared Cydia pomonella (Lepidoptera: Tortricidae) quality and field performance

Abstract

Maximum production and fitness of insect species that are mass‐reared for biological control programmes such as the sterile insect technique (SIT) have benefitted from the employment of quality control and quality management. With a growing interest in the use of SIT as a tactic for the suppression/eradication of key lepidopteran pests, such as the codling moth, Cydia pomonella L. (Lepidoptera: Tortricidae), there is a parallel interest in inexpensive bioassays that can accurately detect differences in insect quality and monitor insect field performance. In this study, we examined laboratory (mating and flight ability) bioassays and field (field cage and open field release) bioassays simultaneously to discern the ability of the different bioassays to predict quality and field performance of codling moths produced in a commercial mass‐rearing facility. Moth quality was degraded by different levels of radiation during the sterilization procedure. Both the laboratory flight bioassay and the field cage bioassay successfully detected quality and performance differences that were relevant to moth performance in the field. However, the study data suggest that the field cage bioassay was a better predictor of the daily performance of males that had been released in the orchard than the laboratory flight bioassay. Conversely, data suggest that the controlled climatic conditions of the laboratory allowed the flight cylinder bioassay to be more sensitive in detecting daily fluctuations in the quality of moths caused by factors within the mass‐rearing facility. Therefore, both laboratory and field bioassays may be required to provide feedback on quality and performance of mass‐reared moths in a SIT programme.

Flight Ability and Dispersal of European Grapevine Moth Gamma-Irradiated Males (Lepidoptera: Tortricidae)

“…Dispersal (mark-release-recapture) experiments were carried out in a vineyard to consolidate and validate the laboratory flight cage data and to study the effect of radiation on field dispersal. Both laboratory and field bioassays should be performed to provide feedback on quality and performance of laboratory-reared moths in any SIT/F 1 sterility program (Carpenter et al 2013). Our experiments showed that the percentage of recaptured L. botrana males was significantly dependent on the applied radiation dose.…”

“…Based upon several studies, inherited sterility or F 1 sterility (SIT/ F 1 , which requires the selection of a radiation dose so that irradiated females are completely sterile while irradiated males are partially sterile) is regarded as the most favorable genetic method for most application against lepidopterans (Bloem et al 1999;Carpenter et al 2001). Consequently, over the last 10 years interest in the use of SIT/F 1 for the suppression/eradication of economically important lepidopteran pests has significantly increased (Simmons et al 2010;Vreysen et al 2010;Carpenter et al 2013).…”

Low-Oxygen Atmospheric Treatment Improves the Performance of Irradiation-Sterilized Male Cactus Moths Used in SIT

“…The laboratory flight bioassay and the field cage bioassay clearly detected quality and performance differences that were relevant to moth performance in the field. However the field cage bioassay was the better predictor of the daily performance of male moths released in the orchard than the laboratory bioassays (Carpenter et al 2013).…”

Influence of Holding Temperature and Irradiation on Field Performance of Mass-RearedThaumatotibia leucotreta(Lepidoptera: Tortricidae)

“…In control programs for lepidopteran pests, desirable performance of sterile insects released in the field would include adequate dispersal throughout the wild insect habitat, competitive pheromone-mediated flight toward the wild insects, and post-release longevity to maintain adequate over-flooding ratios between releases. The effect of different production, handling, processing, and release protocols on these performance attributes can be compared using release/recapture trials in which marked moths are captured within an array of pheromone-baited traps over time (Bloem et al 2004;Carpenter et al 2013).…”

“…Many sterile insect release programs have evaluated the field performance and competitiveness of colony insects by using pheromone traps to conduct release-recapture tests (Henneberry & Keaveny 1985, lance et al 1988, Carpenter et al 2013. The use of field release-recapture bioassays can be a powerful tool in detecting moth fitness differences (Bloem et al 2004), but daily variation in meteorological factors within the field may significantly influence the bioassay.…”