Mating disruption to control the blackheaded fireworm (Lepidoptera: Tortricidae) in organic cranberries using...

We evaluated a mating disruption strategy using a new sprayable microencapsulated (MEC) formulation to control the blackheaded fireworm (BHFW), Rhopobota naevana (Hübner), a major pest in cranberry production. In 4 organic cranberry farms in Quebec (Canada), all the key components of the mating disruption were monitored, including male moth trap catches, female mating status, next-generation larval densities, and crop damage. Adult male populations were monitored throughout the growing season using pheromone traps, and no reduction in captures was observed after MEC application. Female mating status and sex ratio were assessed by capturing adults with a sweep net, followed by sexing and dissection. The number of mated females was significantly reduced by 16% in mating-disruption-treated plots compared to control plots, without affecting the sex ratio. Larval densities were assessed using 30 quadrats in each field, with significantly lower occurrences in mating disruption plots. Crop damage was evaluated at the end of the season, with mating disruption treatment resulting in 59% less damage caused by BHFW larvae. Overall, the MEC formulation shows promise for BHFW management in cranberry production, providing evidence of successful mating disruption, as seen in female mating status, next generation of larval densities, and end-of-season damages while remaining compatible with integrated pest management (IPM) strategies. These findings emphasize the importance of assessing all components of the mating disruption process, since impacts on mating success, offspring development, and crop damage do not correlate with male captures in the present study.