Description:A dark brown to blackish mass of powdery spores replaces the Barley or Wheat head. The spore mass is initially covered by a thin membrane that ruptures soon after the cereal head emerges. Spores are released to infect flowering crops. By harvest only the bare stem of the Barley or Wheat head may remain. Newly infected grain appears normal.
Species Affected:The Barley strain only affects Barely and the Wheat strain only affects Wheat and Triticale.
Biology:Spores carried by wind.
Life Cycle:Spores released as infected heads emerge are released and carried by the wind to infect cereal florets. The fungus grows into the developing cereal seed and the seed looks normal at harvest. After the planting the fungus grows through the plant to form spore masses in the cereal heads.
Origin and History:Distribution:
Significance:Yield loss is proportional to the number of heads infected.
Management and Control:Use seed from uninfected areas.
Thresholds:5 infected heads per hundred heads produces levels of seed infection that may not be adequately controlled by seed dressings. Don't use this seed for planting a crop. Collect plants at heading to determine the levels of disease.
Related and Similar Species:Bunt of Wheat (Ustilago tritici)