Oat leaf rust found in wild oats along roadsides

  • Avon Valley roadsides

David Stead (Anasazi Agronomy) has reported seeing lots of oat leaf rust on wild oats along the roadsides in the Avon Valley. Particularly the Brookton Highway, York–Bruce Rock Road and bits along the Great Eastern Highway.

Rust pustules on an oat leaf.
Oat leaf rust pustules. Photo courtesy of: Faan Carlse (Landmark).

Oat leaf rust is also known as crown rust. The word 'crown' refers to the shape of a type of spore produced by this fungus and is not related to the disease symptoms. The characteristic symptom is the development of round to oblong orange pustules primarily on leaves and leaf sheaths. The powdery spore masses in the pustules are readily dislodged. The pustule areas turn black with age.

Oat leaf rust is potentially a very damaging disease, reducing both grain and forage yields. The fungus is carried over on volunteer oats and wild oats from season to season. 

Foliar fungicide registrations exist for control of this disease, refer to the department’s Registered foliar fungicides for cereals in Western Australia.

It is important that samples of all rusts are sent for pathotype testing. Infected leaf samples should be mailed in paper envelopes (do not use plastic wrapping or plastic lined packages) along with your details and collection information (location, variety etcetera) directly to the Australian Cereal Rust Survey, Plant Breeding Institute, Private Bag 4011, Narellan NSW 2567. Free reply paid envelopes can be ordered from the University of Sydney.

For further details see the University of Sydney's Cereal Rust website and How to prepare and send samples for dispatch to the Australian Cereal Rust Survey.

For more information on oat leaf rust refer to the department’s Oats: leaf diseases webpage.

For more information contact Kithsiri Jayasena, Research Officer, Albany on +61 (0)8 9892 8477 or Geoff Thomas, Research Officer, South Perth on +61 (0)8 9368 3262.