Wheat Common Bunt or Stinking Smut
Location: Head Diseases -> Wheat Common Bunt
Scientific Name: Tilletia caries
- Control Recommendations
- Pesticides
Description:
Infected wheat can often be identified when plants are slightly shorter than healthy plants. Spikelets on infected heads will have a green, greasy appearance. The spikelets also may appear to spread out as the fungus expands within the infected seed. Infected awn cultivars may appear to have shorter awns or no awn production. Seed from infected heads may appear to look more like black balls due to black spore masses that replace what would have been healthy grain. The fungi that cause common bunt or stinking smut can survive between growing seasons for many years on the surface of ealthy seed or in the soil. Early seeding of spring wheat, when soil may be cool and moist, favors germination of the fungal spores. Winter wheat planted when soil temperatures are above 68 F may reduce infection.
When infected seed is squeezed, masses of black spores will emerge that have a smell of rotten fish caused by the trimethylamine produced by the fungus. Hardened spore masses that have shapes similar to miniature footballs may appear on mature heads and kernels. As a combine harvester is run through areas in the field where these infested heads are present, clouds of spore dust will be releases which smell of rotten fish.