12 December 2018

Events held across Australia in October and November 2018 brought together growers, government biosecurity officers, and international experts to consider the threat posed by the spotted wing drosophila (Drosophila suzukii, SWD).

The events were part of a project to improve preparedness for an incursion of SWD by raising awareness of the exotic pest to increase the chance that an incursion would be detected and ensuring tools needed for its eradication are available.

The exotic pest is native to Eastern Asia but developed as a global concern following its spread to North America, South America and Europe.

While most drosophila flies only affect damaged and over-ripe fruits, SWD lays its eggs in a range of ripening fruits before they are ready for harvest.

So, while SWD isn’t considered a ‘true’ fruit fly, its impact could be just as significant and damaging for horticultural industries.

SWD is recognised as being a high biosecurity concern for Australia. The pest reproduces rapidly, can be difficult to identify, and could result in up to 80% losses in susceptible fruit.

Australia’s most susceptible crops are strawberries, cane berries, blueberries and cherries, with summer fruit and table grapes also impacted.

Together, the estimated production value of these industries is over $1.6 billion.

Given the threat that SWD poses, Plant Health Australia is working with cesar and Plant & Food Research New Zealand on a Hort Innovation funded project called ‘Improving the biosecurity preparedness of Australian horticulture for the exotic Spotted Wing Drosophila’.

The project aims to build awareness of the pest and Australia’s capacity to respond to an incursion. The project is also reviewing the available pest management tools for the pest to identify which one are most relevant to Australian conditions.

On 29 October, industry representatives met at a workshop to review current knowledge about SWD and its management and hear from international researchers about their experience with the pest.

Following the workshop, presentations to raise awareness of SWD were held in Wandin (Vic), Launceston (Tas), Coffs Harbour (NSW) and Caboolture (Qld) from 30 October to 2 November.

These events allowed growers from a range of production regions to hear from international experts Professor Rufus Isaacs from Michigan State University, USA, and Bethan Shaw from the National Institute of Agricultural Botany, UK.

In each of their presentations Professor Issacs and Mr Shaw shared how berry industries in their country were impacted by the arrival of SWD, updated attendees on the current knowledge about the pest, and highlighted the strategies that can be used to manage the pest.

Both presenters emphasised the importance of an integrated approach to managing the pest, the value of on-farm hygiene, and the importance of timing harvest carefully.

Developing SWD control programs that are compatible with integrated pest management programs for other pests and cause minimal disruption to established natural enemies is also important.

These were the first part of the project which will run to 2020. It is funded by Hort Innovation with support of the strawberry, raspberry and blackberry, cherry and summer fruit R&D levies.