Disruption of sex pheromone communication in the blackheaded fireworm in Wisconsin cranberry marshes by using MSTRS™ devices

The results of experiments in Wisconsin cranberry marshes by using a novel, controlled release system called the Metered Semiochemical Timed Release System, or MSTRS™, for disrupting pheromone-source location by males of the blackheaded fireworm, Rhopobota naevana (Hübner), are described. During the first flight, disruption (trap catch reduction) of males' ability to locate synthetic sex pheromone lures containing 10 μg of the R. naevana pheromone blend averaged 95.7% in the first grower location and 99.6% in a second grower location, regardless of the MSTRS deployment pattern. However, disruption averaged only 81.7%, 80.7%, and 56.4% for a 12 MSTRS-per-ha cross pattern, a 5 MSTRS-per-ha perimeter pattern, and a 12 MSTRS-per-ha perimeter pattern, respectively, in the third grower site. During the second flight, in which the night-only emission of pheromone was tried, disruption of trap catch averaged 86.7% in the first location overall for all MSTRS configurations, 85.4% in the second location, and 53.8% in the third and poorest disruption location. Significant levels of disruption were achieved season-long regardless of the MSTRS array, but there was no significant difference in disruption efficacy among the three arrays. No significant effect on larval infestation following the first flight was observed in the MSTRS-treated plots, but there was high sampling variability and very low infestation in the check plots, making it difficult to discern effects of MSTRS on larval populations.