Take-all disease (Gaeumannomyces graminis)
It is a soil-borne fungus. It invades and blackens the roots, frequently killing them in the process. Affected stems are black and shiny just above the soil level. This symptom can only been seen by peeling away the leaf sheaths. The disease occurs in slowly widening patches, and in these areas plants with poorly filled or empty ears (whiteheads) may be present. The pathogen survives between crops on cereal roots and stubble. It also attacks barley, oats and rye.
- Rotate with non-susceptible crops such as alfalfa, sweet clover or maize.
- Remove stubble from the fields.
- Avoid continuous cropping with wheat, barley, oats or rye