Key messages
- Russian wheat aphid (RWA) was first detected in Australia in May 2016 south of Tarlee, South Australia.
- RWA was deemed unable to be eradicated following widespread detections in SA and further detections in Victoria and then New South Wales during 2016.
- RWA was not detected in WA following extensive surveillance conducted during June-December, 2016.
- Growers and consultants in WA should remain vigilant in the coming season, continue to report presence and absence of RWA and plant damage symptoms in cereal and grass plants, and be prepared to manage this new pest should it be found in WA and unable to be eradicated.
Results
Immediately following the announcement of RWA in SA, surveillance was conducted by DAFWA staff, growers and consultants to assess 1) the possibility of RWA being found in WA and 2) whether isolated cases of RWA in WA may be contained and eradicable.
Between 1 June and 31 December 2016, 681 reports were submitted to DAFWA of absence of RWA and presence or absence of other aphids on cereal or grass plants. This included 485 cases where cereal or grass plants were inspected for RWA and none were found. Furthermore, 196 reports were made where other aphid species were found on these hosts in the absence of RWA. Most of these aphid reports (104) were identified as the common oat aphid.
Conclusion
If RWA is found in WA in the coming growing seasons, it is anticipated that it will be manageable with insecticide applications where RWA populations reach damaging levels. However, because RWA seems to be able to cause more damage than the common oat or corn aphids (because of toxins injected into the plants), it is probable that cereal crops will need to be monitored for this pest and more often (than oat and corn aphids) to prevent outbreaks and subsequent economic damage.