The photo below is a sample of spring wheat, cvr Pasteur, from the Rivers area of Manitoba that shows symptoms of melanism. Typicially just glumes are affected, but the symptoms of melanism can sometimes extend down the stem under the head. In the photo, symptoms are evident on the glumes as well as a bit of the stem on two of the plants. According to the APS wheat disease compendium, melanism can occur due to genetics, as a response to a nonspecific stress, or copper deficiency and can occur on glumes, awns and/or stems.
Submitted by: Pam de Rocquigny, Provincial Cereal Crops Specialist, Manitoba Agriculture