The Department of Industry, Tourism and Trade is increasing plant surveillance after a confirmed single sample of a leaf-mining fly in the Katherine region. 

The suspected Liriomyza trifolii was discovered after the Plant Biosecurity team increased surveillance for the plant pest following suspected samples were found in Western Australia and Queensland. 

There are many species of Liriomyza, including a native Australian species and other Australian flies which can appear to be similar in appearance. To confirm whether a sample is one of the 4 priority plant pests, the insects are subject to further testing. On Friday, the Plant Biosecurity team received morphological and molecular (DNA sequencing) confirmation that the single sample caught in Katherine is an American serpentine leafminer fly. 

In response, surveillance, trapping and community engagement about biosecurity threats will be increased across the Top End. 

American serpentine leafminer flies are a pest because they lay their eggs on plant leaves and the hatched larvae burrow into the leaf, destroying the inner tissue. This makes it harder for affected plants to photosynthesise. 

Affected plants may have wilted leaves or drop damaged leaves. Fewer leaves may also cause sunburn on fruit and reduced yield. Stressed and damaged plants are also more susceptible to bacterial and fungal diseases. 

For more information about the steps being taken by governments across northern Australia and information for growers and the public, head to the website: www.outbreak.gov.au/current-responses-to-outbreaks/american-serpentine-leafminer 

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 Chief Plant Biosecurity Officer, Dr Anne Walters

“The Department of Industry, Tourism and Trade acts swiftly and proactively to detect and manage any potential biosecurity threats that could impact the Northern Territory’s agriculture industries. 

“After suspected detections were made during routine plant health surveys undertaken by the Australia Government’s Department of Agriculture, Water and the Environment’s Northern Australia Quarantine Strategy staff alongside state government teams in Queensland and Western Australia, we immediately stepped up our surveillance. 

“Yellow sticky traps deployed across the Top End as part of our Psyllid trapping program were examined to see whether leafminer flies had been caught and this was how we detected the Liriomyza trifolii sample from Katherine. We’re also examining extra traps that have been laid, and will deploy more throughout Katherine, Darwin and Palmerston from Monday, 9 August 2021. 

“We’re asking growers and the public to look out for any symptoms of leafmining activitiy or any symptoms they haven’t seen before and to report this to the department if they think their plants have been affected.

“We encourage anyone moving plants, plant products, or packaging from Kununurra to the Northern Territory to be vigilant so as to prevent the continued spread of this pest to other areas where they may damage crops. It is important that we all work together to protect our valuable industries and support our local growers.”

Media contact: Department of Industry, Tourism and Trade – 0409 640 859