Jessica Lye Spotted Wing Drosophila (Drosophila suzukii), a native to Eastern Asia, is rapidly becoming a global concern, having recently spread to North America, South America and Europe.
With a short generation time, the ability to reproduce on a wide variety of soft-skinned fruits, and cryptic appearance, this fly is of high biosecurity concern to horticulture.
An outbreak in Australia would have a significant impact. While crop losses of 20-40% are commonly reported, if left unmanaged, losses from this pest could reach 80% in susceptible fruits.
Amongst the most susceptible crops are strawberries, caneberries, blueberries and cherries, with summerfruit and table grapes also impacted. The estimated production value of these industries is over $1.6b.
This exotic fruit fly hit the headlines in 2009 following reports of unusual damage to a range of soft fruits in California, USA. Damage had been observed the previous year, but the belief that this was an endemic species of Drosophila attacking damaged or over-ripe fruit meant that no action was taken.
When the pest was accurately identified it was realised that this was a species capable of damaging fruit prior to harvest. This is possible because Spotted Wing Drosophila has a serrated ovipositor, adapted to piercing the skin of developing fruit.
As globalisation continues, our biosecurity system will come under increasing pressure.
There are hundreds, and sometimes thousands of pest interceptions at Australian ports and other high-risk entry sites every year.
However, while our biosecurity system can reduce the risk of pest incursion, or catch pests at the border, some pests are not identified until they enter and establish in Australia.
This is where early detection and response mechanisms become critical.
Acknowledgements
We are partnering with Plant Health Australia (project lead), and Plant & Food research NZ to increase preparedness for spotted wing Drosophila.
This project has been funded by Hort Innovation, using the strawberry, raspberry and blackberry, cherry and summerfruit research and development levies and contributions from the Australian Government. Hort Innovation is the grower-owned, not-for-profit research and development corporation for Australian horticulture.
Cover image: Photo by Hannah Burrack, North Carolina State University, Bugwood.org, CC BY 3.0 US
