Diseases in Wheat - In Crop
- Rusts are the most important foliar diseases of wheat in Australia
- Compared to stripe and stem rust, leaf rust is potentially the least damaging, but in most seasons conditions are conducive for this disease
Leaf rust forms circular/oval orange-brown pustules that are raised above the leaf surface
The pustules are mainly confined to the leaf surface and can be rubbed off with a finger
Later in the season, black teliospores develop on mature plants, usually on the under surface of the leaf or on the leaf sheath
- In Victoria, severe leaf rust infections can reduce grain yield by more than 20 per cent in susceptible varieties, and can also reduce grain quality.
In most parts of Victoria leaf rust is effectively controlled with resistant varieties, but it can cause problems in areas where susceptible varieties are grown. Heavy grazing or the use of herbicides during autumn to remove self-sown susceptible wheat will reduce the amount of rust in following crops. There are seed treatments available which will suppress early infections of leaf rust. There are a number of foliar fungicides registered for the control of leaf rust in wheat. Fungicides should not be regarded as a substitute for growing resistant varieties.
Links and Resources
DAFWA - Farmnote 456. Leaf rust
Page contains information on cereal seed dressing and in-furrow fungicides used for leaf rust, disease diagnosis, cautions, and further contacts. Page last updated 2011.
DEPI VIC - Identification and management of field crop diseases in Victoria. - Leaf rust of wheat
Symptoms, overview of leaf rust in Victoria, economic importance, disease cycle and management. Published 2012.
DEPI VIC - Leaf rust of wheat
Symptoms, overview of leaf rust in Victoria, economic importance, disease cycle and management. Published 2008, updated 2012.
Victorian winter crop summary 2014 - Leaf rust
Table 6: Wheat disease guide. Page 11. Causal organism, symptoms, occurrence, inoculum source, and control. Updated annually.