Aphids and beneficial insects are active in crops
- South Stirlings
Entomologist Dusty Severtson (DPIRD) has found cabbage aphids along crop edges in flowering canola crops near Toodyay and Northam. He has also found turnip aphids along the crop edges of flowering canola crops near Goomalling.
David Stead (Anasazi Agronomy) has been finding turnip and cabbage aphids at below threshold levels in canola crops through Northam, York and Beverley. He noted that some parasitised aphids (mummies) could be seen, the crops will continue to be monitored for aphid population increases.
DPIRD staff have noted that a canola crop near Northam which had cabbage aphid-infested racemes on some plants (up to 15cm long aphid colonies) up to 6 weeks ago along the crop edges have decreased to almost undetectable levels this week with parasitized aphids easily found on raceme terminals. This crop had been monitored for parasitoid wasps using yellow sticky traps which indicated that the wasps had been detected in low numbers up to eight weeks ago and increasing to huge numbers last week. It is expected that the high parasitoid wasp numbers in the paddock currently should prevent further aphid infestations from developing into damaging numbers. For more information, see the department’s Know what beneficials look like in your crop page.
Crop protection officer Alice Butler (DPIRD) has reported finding cabbage aphids in a late flowering 44Y27 canola crop at South Stirlings.
Luke Marquis (South East Agronomy Services) recently found large numbers of green peach aphids in a late sown barley crop near Hopetoun.
For more information on identifying and managing canola aphids refer to the department’s;
- Aphid management in canola crops page
- Diagnosing canola aphids page
- Aphids in your crops YouTube video.
Growers and consultants are urged to continue checking for the Russian wheat aphid
It is important that growers and consultants continue to monitor WA cereal crops for the Russian wheat aphid (RWA). This pest has not been found in WA. In addition to feeding damage it can inject toxins into cereal plants further stunting them and reducing yields. For more information on RWA refer to the department’s Diagnosing russian wheat aphid and Biosecurity alert - Russian wheat aphid pages.
Remember, if you are unsure of what aphid species you are finding in your crops you can use the PestFax Reporter app to attach up to three images of the aphid(s) and request that a department entomologist identify or confirm the aphid species via an email or phone response.
For a list of insecticides registered for use on aphids see the department’s 2018 Winter/spring insecticide guide.
For more aphid information contact Dustin Severtson, Development Officer, Northam on +61 (0)8 9690 2160, Alan Lord, Technical Officer, South Perth on +61 (0)8 9368 3758 or Svetlana Micic, Research Officer, Albany on +61 (0)8 9892 8591.