What was it all about?

This investment, which ran from 2020 to 2022, investigated the use of parasitoid wasps as a potential strategy for fruit fly management. The research focused on improving knowledge of parasitoid distribution in Australia, developing new protocols for mass-rearing releases of fruit flies using parasitoids, and conducting trial releases in fruit orchard sites across Victoria.

The use of natural enemies such as parasitoids against insect pests is regarded as a core component in sustainable pest control and will provide horticulture industries with another method to use for fruit fly management.

New information on the distribution of fruit fly parasitoids in Australia was delivered through a comprehensive review of published and unpublished data. This information paved the way for a new phase of Australian fruit fly parasitoid research.

Fruit fly populations in Victoria have increased significantly over the last decade, yet fruit fly parasitoids have not been identified for the State. Researchers conducted survey work, collected fruit fly-infected fruits, and discovered the first record of a tephritid fruit fly parasitoid in Victoria, indicating that this insect may be beginning to establish in the region. As its establishment rate may be slow, a cost-benefit analysis showed that fast-tracking this process could be a worthwhile investment for the horticultural industry.

Researchers selected two parasitoid species as the most suitable candidates for fruit fly biocontrol, with wild species collected from host plants in Queensland. Protocols to mass-rear these insects were developed, and pilot releases took place across Victoria in two consecutive growing seasons. 95,000 parasitoids were released in 19 individual events at three orchards and nine urban sites across the Sated. Results demonstrated the potential for both species to become established in Victoria, persisting seasonally in the environment, reproducing, and dispersing from release sites.

The use of parasitoids for fruit fly biocontrol is promising, particularly for area-wide management of fruit flies in urban towns and cities, with further research required.

ACT NOW

Download information about the use of parasitoids to control Qfly populations, and view a workshop presentation delivered to Cherry Growers Australia in June 2021.

Read more about the project outcomes in these articles:

• Natural predators another link in biocontrol chain, published on the Citrus Australia website in April 2021
• Parasitoid wasps: The focus of a new biocontrol program for Queensland fruit fly, published on the AUSVEG website in May 2021.
• Parasitoid wasps: The focus of a new biocontrol program for QFF, published on the Australian Tree Crop website in June 2021.
• Using natural enemies to control fruit fly, published in the Queensland Fruit Fly Newsletter by the Greater Sunraysia Pest Free Area team in September 2021.