Powdery mildew found on wheat volunteers down south
Andrew Heinrich (Farm and General) has found powdery mildew on Mace wheat volunteers near Coomalbidgup. Andrew reported that the volunteers have pustules scattered over leaves and will be sprayed out over the next week but the problem already exists.
Powdery mildew appears as fluffy, white powdery growths of fungal spores on the leaf surface. The fungus survives as fruiting bodies on stubbles that release spores after autumn rains. Spores can spread over long distances.
Plant pathologist Geoff Thomas (DAFWA) advises that given the amount of powdery mildew in crops over the last couple of seasons, there is an ongoing high risk of powdery mildew in wheat crops this season, particularly where surviving volunteer regrowth may already be multiplying early season inoculum.
Applying in-furrow or seed dressing fungicides can reduce your risk of early infection of powdery mildew in susceptible varieties. For more information see DAFWA’s Seed dressing and in-furrow fungicides for cereals in Western Australia. Later in the season a registered foliar fungicide can be used to spray infected plants and provide protection from yield losses. Know the latest disease ratings of your varieties and plan accordingly. Crop Variety Guides are available for all grains on the department’s website, which document the disease susceptibility for each variety.
For more information contact Geoff Thomas, Plant Pathologist, South Perth on +61 (0)8 9368 3262.