Barley and wheat disease update
Barley leaf rust
Plant pathologist Andrea Hills (DPIRD) reports finding some barley leaf rust (BLR) in a flowering barley crop (variety unknown) near Cascade.
BLR develops rapidly in moist conditions when temperatures are between 15-22°C.
Growers and consultants are strongly urged to participate in the Australian cereal rust survey and submit samples to the University of Sydney, Private Bag 4011, Narellan NSW 2567 for pathotype testing if they are finding rusts in crops.
For more information on BLR and how to manage it refer to the department’s Diagnosing barley leaf rust page.
Barley loose smut
Plant pathologist Kith Jayasena (DPIRD) reports that a LaTrobe barley crop north of Woogenellup has loose smut. The crop’s seed was treated with Systiva®.
Barley loose smut is a fungal disease affecting seed heads, which can cause yield losses. In plants grown from infected seed, florets are replaced with a compact mass of dark brown-black powdery spores at heading. These spores are dispersed by wind to infect adjacent plants and produce the next generation of infected seed. Infection is favoured by rainfall and high humidity during flowering. In the paddock look for scattered plants with black heads or bare flower stalks.
For more information refer to the department's Diagnosing barley loose smut page.
Wheat powdery mildew
James Bee (Elders) has reported finding powdery mildew on Mace wheat near Tenterden. He estimated 30-60% of the crop was infected. James commented that powdery mildew was infecting Mace and Scepter, and that there was some early light infection in Zen and Ninja wheat crops.
James also commented that there was lots of wheat powdery mildew in the Gairdner area too.
Scepter and Zen are both rated susceptible to very susceptible (SVS) to powdery mildew. Nina is very susceptible (VS) and Mace is rated moderately susceptible to susceptible (MSS). Therefore under favorable weather conditions infection could multiply rapidly in all four varieties.
For more information on wheat powdery mildew refer to the department’s Managing powdery mildew in wheat page.
Fungicide application information
Fungicide choice needs to take into account the diseases present in a crop. Where a variety is susceptible to both of the diseases present, a fungicide that is registered to control both of them is required. For more fungicide information refer to the department’s Registered foliar fungicides for cereals in Western Australia page.
For more information contact Kithsiri Jayasena, Plant Pathologist, Albany on +61 (0)8 9892 8477, Geoff Thomas, Plant Pathologist, South Perth on +61 (0)8 9368 3262 or Andrea Hills, Plant Pathologist, Esperance on +61 (0)8 9083 1144 or Ciara Beard, Plant Pathologist, Geraldton on +61 (0)8 9956 8504.