Thrips predator efficacy testing in strawberries
This project with Strawberry Growers New Zealand focused on the control of thrips, in particular the species Frankliniella intonsa (intonsa). Thrips continue to be a limiting pest of strawberries in Auckland and Waikato, causing major fruit damage from mid-summer onwards.
The project had two components, a landscape survey to determine host plants thrips populations build up on prior to migrating onto strawberries in mid-summer; and predator efficacy testing.
The effectiveness of three different predatory insects, minute pirate bug, green lacewing, and predatory mites against pest thrips was investigated on strawberries in a greenhouse setting.
The landscape survey found white clover is a significant alternative host for two species of thrips, Western Flower Thrips (WFT) and intonsa, and should be considered as a potential source of both thrips and predators when managing the pests in strawberry crops. While intonsa rose to high numbers in strawberries for a short time in late January and early February, WFT were the more abundant thrips species.
Predator efficacy testing showed the currently available commercial predators (predatory mite Neoseiulus cucumeris and minute pirate bug Buchananiella whitei) ate more thrips than the alternative biological control agents tested. Â
The choice tests with different life stages of thrips indicated that all predatory insects prefer younger thrips life stages and therefore any predator programme must focus on managing thrips early in their population build-up rather than on predation of adult thrips.
As thrips are also pests of vegetable crops, project learnings about the biological control options for thrips attracted cross sector interest.
Check out Grower Resources, or read more about the project below:
- November 2024: Strawberries project seeks biocontrol options for thrips
- May 2025: Survey work identifies pest host plant
- August 2025: Strawberry project supports importance of timing in BCA useÂ
Grower Resources
The updates linked below is technical information provided to growers about the project by SGNZ’s representative on the project, Molly Shaw, of Berryworld.
