| Abstrakt: |
Pheromone-based mating disruption of lepidopteran pests (Tortricidae) of pome fruits using hand-applied dispensing systems has become standard management practice for many producers in western North America. Sprayable microencapsulated (MEC) pheromone formulations that enable the application of pheromone controls with other orchard sprays and assist in the development of multispecies mating-disruption systems are currently under development. Responses of maleChoristoneura rosaceana(Harris) andPandemis limitata(Robinson) (Lepidoptera: Tortricidae) to calling females in clean air, and air treated with their major pheromone component (Z)-11-tetradecenyl acetate (Z11-14:OAc), released from a 3M sprayable pheromone formulation containing proprietary 3M Phase I microcapsules, applied at doses of 1, 10, and 100 mg of active ingredient (ai) m−2 to the upwind end of a flight tunnel (equivalent to field rates of 10, 100, and 1000 g ai ha−1) were compared in laboratory flight tunnels. In both species, disorientation was found to be dose-dependent, because relative to male orientation to calling females in clean air, the orientation of maleP. limitatawas disrupted 23.3, 46.3, and 71.3%, and orientation by maleC. rosaceanawas disrupted 31.6, 37.7, and 45.8% by treatment doses of 1, 10, and 100 mg m−2, respectively. Latency of male responses to calling females in a background ofZ11-14:OAc relative to responses in clean air was also dose-dependent. Albeit short, the disruption lasted 26, 74, and 218 h in P. limitataand 30, 54, and 174 h inC. rosaceanaat each application rate, respectively. Disruption by pheromone treatment was greater inP. limitatathan inC. rosaceana. This difference may be correlated with species’ differences in the pheromone release rates of females. Mechanisms of disruption invoked by this 3M MEC pheromone formulation are discussed in relation to issues of its longevity and observed differences in the effects against the two species. It appears possible to evaluate relative activity of MEC pheromones in a laboratory setting which may aid in development of new formulations for mating disruption. [ABSTRACT FROM AUTHOR] |
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