The Department of Industry, Tourism and Trade is working with national experts following confirmation of a leaf-mining fly in the Greater Darwin region.
The Plant Biosecurity team had increased surveillance for the plant pest after suspected samples were found in Western Australia and Queensland. This led to the detection of a single fly on traps located in the Katherine region last week.
This week, the team detected Liriomyza trifolii (American serpentine leafminer) in the Greater Darwin region, which was confirmed through DNA testing late yesterday afternoon.
These samples have been discovered as part of increased surveillance, industry reporting, and community engagement about this biosecurity threat.
There have been multiple detections of this pest across northern Australia. Surveillance is still being conducted to determine the distribution of this pest.
Members of the public and growers are being encouraged to help the department’s Plant Biosecurity team by reporting suspected leafminer flies or damage. The damage will look like silver squiggly tracks on the leaves of plants. Reports from the community will lead to increased knowledge of the distribution of the pest, while also informing management efforts.
There are many species of Liriomyza, including a native Australian species and other Australian flies which can appear to be similar in appearance. DNA testing is needed to confirm whether the type of leafminer is 1 of the 4 considered to be a plant pest.
Leaf miners are small flies whose larvae feed internally on plants. Severe infestations of American serpentine leafminer may result in premature leaf drop, poor growth, and reduced crop yields, so it is considered a National Priority Plant Pest in Australia.
For more information head to the Department of Industry, Tourism and Trade's website.
Suspected cases of American serpentine leafminer should be reported to the department by calling the Exotic Plant Pest Hotline on 1800 084 881.
Quotes from the Department of Industry, Tourism and Trade’s Senior Principal Entomologist, Dr Brian Thistleton:
“Yellow sticky traps deployed across the Top End helped us detect the sample from Katherine. The Darwin sample was detected as damage on plants following a report from a grower and yellow sticky boards also allowed us to find flies at that site.
“More traps have been set in the Darwin, Palmerston and Katherine region to help with our ongoing response.
“We are grateful to growers and members of the public for reporting damage to plants suspected to be caused by this pest. This helps with our surveillance and to inform further work aimed at ensuring we can implement the most effective management approaches for this pest.
“In the case of the Darwin detection, it was fantastic to see a single report of a suspected case lead to a quick confirmation of a further detection. This new information allows the department to respond quickly to the detection and to develop the most effective and proactive approach to managing this pest.
“We will continue to work with experts in other northern jurisdictions to coordinate research or management efforts.
“As we examine the extra traps that have been set out by the department, we’re asking growers and the public to monitor for symptoms of leafmining activity and report this through the Exotic Plant Pest Hotline on 1800 084 881.”
Quotes from the Northern Territory Farmers Association (NT Farmers) CEO, Paul Burke:
"NT Farmers are committed to working with the department and growers to effectively manage and control this pest. I would like to thank everyone involved in the response so far.
"Industry is keen to engage in the development of an integrated pest management solution in partnership with the Biosecurity division.
"American serpentine leafminer presents a significant threat to farmers across the north and to the NT economy, I urge anybody who suspects that they have the pest to contact the Exotic Plant Pest Hotline on 1800 084 881.
"We are at a critical stage, if we can act early and quickly we have a chance of controlling this biosecurity incursion. We depend on growers and the public to report potential sightings to the hotline.
"The leafminer has the potential to threaten a wide variety of crops in the Territory including vegetables, melons and nursery products."
Media contact: Department of Industry, Tourism and Trade – 0409 640 859
NT Farmers – 0405 287 344