GREEN peach aphid (GPA) is being found at low levels in canola crops in parts of South Australia but experts consider it poses little or no risk to crops.
Insecticide treatment at this point in the season is unlikely to provide an economic benefit.
The South Australian Research and Development Institute (SARDI) Entomology Unit has identified GPA specimens from Rhynie in the Lower North and Lameroo in the Mallee.
“Reports also suggest that many canola crops between Lameroo and Bool Lagoon in the South-East contain low levels of GPA and occasional virus-like symptoms, however, there has been no evidence of damaging infestations,” entomologist, Kym Perry, said.
“During the cold and wet conditions of winter, there is likely to be little aphid activity or risk of population build-up. In the vast majority of cases, treatment will not be necessary, even where aphids are present.
“To help manage resistance and off-target impacts, we advise against the unnecessary use of insecticides.”
More information on GPA management is contained in the GRDC’s Crop Aphids Back Pocket Guide available at https://grdc.com.au/CropAphidsBackPocketGuide, and the southern PestNotes fact sheet available at http://www.pir.sa.gov.au/pestnotes.