A new $4.7m levy-funded fruit fly project aims to harness genetic selection to ramp up the fight against Queensland fruit fly by ensuring all sterile fruit flies released into the environment are male.
Led by Macquarie University and funded by Hort Innovation under the Hort Frontiers Fruit Fly Fund, a team of national scientists and international collaborators will work together on the Sex selection genes from fruit fly species for use in SITplus project to identify the genetic code that enables the elimination of female fruit flies in overseas sterile insect breeding programs. Once identified, these characteristics can be bred into a selection of Australia’s Queensland fruit fly (Qfly).
Sterile Insect Technique (SIT) is a method of pest control that uses the strategic release of millions of sterile fruit flies to greatly outnumber the wild male population and, as a result, limit the opportunity for wild females to mate with wild males and reproduce.
The new National Sterile Insect Facility in Port Augusta, 350 kilometres from Adelaide, has the capacity to produce 50 million sterile flies each week but currently produces equal numbers of male and female flies which cannot be effectively sorted to remove the females prior to release. Releasing sterile females dilutes the effectiveness of the program by reducing the ratio of sterile males to females and likelihood of sterile males mating with wild females.
Hort Innovation’s SITplus program coordinator Dan Ryan likened it to a dance hall where a single girl in a dance hall was likely to get a lot more attention than in one full of other girls.
“This research is important because it has been shown that SIT is more effective if only males are released,” he said.
“Qfly costs the Australian horticulture sector $300 million per annum in lost markets by impacting production in two ways – damaging produce in the field leading to yield loss, and by affecting the market access or acceptability of the crops in international markets.”
While naturally-bred male-only ‘genetic sexing’ strains are available for some overseas fruit flies, the project aims to develop the technology for the Qfly, which is the most significant insect threat to Australia’s $12.9 billion horticultural industry.
Partners at the United States Department of Agriculture (Hawaii), Giessen University (Germany), and Insect Pest Control Section of the Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture will lead efforts to identify genes in overseas species, while partners at CSIRO and the South Australia Research Development Institute will lead efforts to develop these traits in the Queensland fruit fly.
Professor Phil Taylor from Macquarie University’s ARC Centre for Fruit Fly Biosecurity Innovation said sustainable, environmentally benign approaches to the management of Queensland fruit flies was urgently needed to protect Australia’s fruit production and trade.
“Producing male-only sterile fruit flies will be far more efficient and cost-effective in the fight against this destructive pest,” he said.
“We are looking at innovative science to produce male only flies for release, which will in turn, greatly reduce production and release costs and provide a framework of integrated ecological and behavioural science which can maximise the impact of sterile flies when deployed in Australia.”
The outcome of this disruption to mating is the suppression of subsequent generations of wild flies.
Using SIT to combat Qfly also gives greater protection to the honeybee industry through reduced chemical impacts and increased pollination rates.