Dwarf bunt will cause excessive tillering and stunting of the plant. Leaf lesions begin on the lowest leaves and tend to be irregular in shape, becoming pale, straw coloured and slightly necrotic (more common on winter wheat). It can cause loss of both yield and grade.
In severe years, some fields have over 50% bunt-infected plants.
When infected grain is harvested or crushed, bunt balls rupture, releasing their spore contents and, contaminate the grain. The pungent, fishy odour of the spores is another characteristic of the disease. The spore cloud and the distinctive odour are the first signs that a crop may have the disease. Many importing countries have zero tolerance for bunt-contaminated wheat shipments.