A breakthrough from researchers in La Trobe’s School of Agriculture, Biomedicine and Environment and their collaborators at Agriculture Victoria has the potential to help control the destructive behaviour of the Queensland fruit fly.
A native pest, the Queensland fruit fly presents a significant threat to horticulture. It infests fruit and fruiting vegetables by laying eggs in ripe fruit, which results in decay and loss of crops.
Professor Coral Warr, Associate Dean of Research and Industry Engagement and lead researcher, says there is a pressing need for new ways to control this destructive pest.
“Half of Australia’s $15 billion horticultural industry is highly susceptible to Queensland fruit fly. Effective insecticides were recently withdrawn due to environmental impact concerns, so there is an urgent need to identify new ways to control it.”
The solution, says Professor Warr, may be found in the fly’s sense of smell.
“The behaviours of many insects, including those of major agricultural pests like the Queensland fruit fly, are guided by smell,” explains Professor Warr.
“They use odorant receptor proteins to detect the volatile chemical compounds given off by plants, helping them find somewhere to lay their eggs. Up until now, we have known very little about the specific type of odorant receptor proteins that the Queensland fruit fly uses to find host plants.”
As part of a research collaboration with Alex Piper and Paul Cunningham from the Invertebrate and Weed Sciences program at Agriculture Victoria, La Trobe PhD student Stephen Penrose has identified all the odorant receptor genes in the Queensland fruit fly.
“We found that the Queensland fruit fly has many copies of some genes compared to related species, and we think these may be important for host detection. If this is correct, we may be able to use this knowledge to develop new strategies to modify the behaviour of the Queensland fruit fly, with minimal impact to the environment or other species,” says Stephen.
To test their idea, the researchers will use powerful genetic approaches to study gene function by expressing the Queensland fruit fly receptors in the genetic model insect, Drosophila.
“We will then use this information and work with Agriculture Victoria and other collaborators to generate knockouts, which is when certain genes are removed or inactivated in the Queensland fruit fly, and then study the effect on their ability to find their host plants. We hope this will help us determine exactly which genes are required for host detection,” says Professor Warr.
“This is an exciting breakthrough in the search for an alternative control method for the Queensland fruit fly, with huge potential for benefits in the horticultural industry.”
