Oat disease update

Septoria avenae blotch

  • Narkal

Oats leaves affected by septoria avenae blotch.
Oat leaves affected by septoria avenae blotch. Photo courtesy of: Robert Loughman (DAFWA).

Matt Willis (Elders) has reported septoria avenae blotch in tillering Wandering oats in Narkal.

Symptoms can appear as brown to purple spots on leaves developing into light and dark brown blotches, with dark brown centres. They are restricted and distinct at first but may enlarge to cover most of the leaf.

This topic has been covered in the Septoria avenae blotch in oats article in PestFax Issue 12.

For more information refer to the department’s Diagnosing septoria avenae blotch in oats and Oats: leaf diseases webpages.

Stem rust

  • Kumbarning

A close up photo of stem rust on an oat plant
Stem rust on an oat plant. Photo courtesy of: Jessica Smith (DKT Rural Agencies).

Jessica Smith (DKT Rural Agencies) has reported stem rust in flowering Yilgarn oats in Kumbarning. It is a feed crop undersown with serradella. Jessica has found a hot spot infection, less than 15m in diameter in the crop, with a few plants having a couple of spores on each stem.

Stem rust can be identified by large reddish-brown pustules, oval or elongated in shape, on stems and sometimes both sides of leaves and leaf sheaths in oats.

For more detail on this disease and how to manage it refer to the department’s Stem rust found in oat volunteers in Wagin article in PestFax Issue 11 and Diagnosing stem rust in oats page.

For more information contact Geoff Thomas, Research Officer, South Perth on +61 (0)8 9368 3982.