Diagnosing downy mildew in cereals

A fungal disease favoured by waterlogged conditions.

Mature plants: Twisted, fleshy, distorted heads
Young plants: Yellow leaves, severe stunting, excessive tillering.

What to look for


  • Young plants: yellow leaves, severe stunting, excessive tillering
  • Mature plants: Thickened, leathery, twisted leaves and twisted, fleshy, distorted heads.

What else could it be

Condition Similarities Differences
Diagnosing group I herbicide damage in cereals Head distortion Downy mildew is restricted to wet areas
Diagnosing seed gall nematode Head distortion Seed gall nematode causes seeds to be replaced by small black galls

Where did it come from?

Wet conditions
Wet conditions
  • Downy mildew is favoured by waterlogged conditions.

Management strategies

  • Treatment not warranted.

Where to go for expert help

DDLS Seed Testing and Certification
+61 (0)8 9368 3721
Page last updated: Wednesday, 1 July 2015 - 11:28am