Abstract: The sustained release and field mating disruption efficiency of the dispersive isotropic preparation of Grapholita molesta was tested using the core material (Z)-8-dodecenyl acetate of the sex pheromone of G. molesta, with cardboard and plastic bag used as the sustained-release materials in preparing the dispersive isotropic preparation of G. molesta. The effects of different sealing methods, temperatures, cardboard thickness, and plastic bag thickness on the release rate were measured in the laboratory. A field experiment was conducted at a dosage of 45 pieces/hm² to compare the rating of mating disruption of the dispersive isotropic preparation with plastic bag thicknesses of 6, 8, 12, and 20 filaments. The results showed that the release rate of the dispersive isotropic preparation in the heat sealing mode is longer than that in the normal and vacuum sealing mode. As the temperature increased, the release rate accelerated and the duration was shortened. However, the thickness of paperboard and plastic bag had little influence. With the increase of the thickness of the plastic bag, the rating of mating disruption gradually decreased. When the thickness of the plastic bag was 6 filaments, the rating of mating disruption reached more than 90.0%. The research results provide a theoretical basis for the development of application technology of the dispersive isotropic preparation of G. molesta.

Key words: Grapholita molesta, dispersive isotropic preparation, (Z)-8-dodecenyl acetate, release rate, rating of mating disruption