Trapping efficacy in table grape vineyards for area wide management of Queensland fruit fly (TG19001)

What was it all about?

From 2020 to 2022, this investment further developed mass trapping methods as a tool to assist in the control of Queensland fruit fly and evaluated the effectiveness of trapping at decreasing fly populations for table grape growers.

Working across the 2020/21 and 2021/22 seasons, this project looked at how mass trapping might be used to assist control. The research involved four case studies in commercial vineyards and experimental work; three focused on whether protein baited traps and/or a new Agriculture Victoria Research AVR sticky trap might be used (building on recent research in pome and stone fruit orchards) and one explored trap placement within and around vineyards.

The trap-related research led to several important findings:

• The new AVR Trap was not as effective as the protein baited trap. Being a sticky trap, it was susceptible to dust and debris due to frequent dust storms in the area.
• Trapping around the perimeter of the block was significantly more effective in catching flies compared to placing traps on interior vines
• Nearby fruit trees harboured fly population “hot spots” with growers needing to consider the increased risk this poses to Queensland fruit fly infestations in vineyards.

Vineyards differ markedly from fruit orchards in the shelter they provide for adult fruit flies, and the increased catches of flies around the perimeter may be due to flies moving in and out of the crop on a daily basis.

The fourth case study using RapidAIM traps (which collect real-time data on male fly catches) provided more evidence that perimeter traps outperform interior traps. A laboratory study explored whether these traps could be modified to target female flies. It found that the use of protein bait within the traps would catch low numbers of females and the addition of a red visual cue increased trap captures in the laboratory, though field trapping was still low.  

A grower survey provided several important grower perception insights, including stigma related to an infestation and the cost of mass trapping, and an experiment demonstrated that some grape varieties are more attractive to female flies than others, with field trials needed to validate this.

The project provided new knowledge to help inform table grape growers on the potential for mass trapping of Queensland fruit fly in their vineyards, such as:

• Trapping around the perimeter of the vineyard and in nearby host fruit trees might be the most cost-effective approach for both male and female mass trapping strategies, though more research is needed.
• Sticky traps are not recommended in and around Mildura, with protein traps currently the best option
• Further research could develop a synthetic fruit-lure trap that instead uses an insecticide or biopesticide as the killing agent.

ACT NOW

Read these two articles about the project and its results, published in Vine Magazine:

• Grand designs: Designing a female mass trapping strategy for managing fruit flies in table grapes, May 2020 edition, page 28.
• Mass trapping female fruit flies in vineyards, August 2021 edition.

Visit the Australian Table Grape Association website for industry information and resources.