There are three basic methods by which a pest’s sex pheromone can be exploited for control:
- Mating disruption where the pheromone is used alone to interfere with the normal attraction of males to females by providing false trails and/or sensory overload
- Mass trapping where the sex pheromone is used to attract males to a trap where they are captured and killed physically
- Attract and kill where the sex pheromone attracts males to a device or place where they come into contact with an insecticide
Pheromone attract and kill:
The sex pheromone is incorporated into a material together with an insecticide (usually a synthetic pyrethroid).
- Blobs of the material are extruded onto the trunk and branches of trees throughout the orchard (typically 1-2 blobs per tree) at the start of moth flight, as indicated by pheromone traps.
- The males attempt to mate with the blobs, picking up a dose of insecticide in the process.
- The technique is effective and uses a fraction of the amount of insecticide used in an insecticide spray treatment.
- However, no product is approved for use in the UK currently.
Insecticide resistance
Strains of summer fruit tortrix moth, that are less susceptible to conventional insecticides than strains that occur in unsprayed orchards, have been shown to occur in the UK. However, the reduction in susceptibility is small.