Wheat florets with fusarium head blight
Wheat florets with fusarium head blight and showing orangish sporulation. | photo: Kelly Turkington

Fusarium head blight (FHB) on cereals increases production costs, reduces yields, decreases grain quality and may limit crop marketing opportunities. The production of the mycotoxin, deoxynivalenol (DON), by some fusarium species further limits the grain’s end uses and marketing potential, as most importing countries have strict limits on DON levels.

To help keep marketing options open and maximize return on investment, Cereals Canada recommends growers use the following practices to manage the disease and to reduce the presence of FHB on seed:

  1. Grow Disease-Resistant Varieties. Growing the most disease-resistant varieties available in areas at risk for FHB is one of the most important decisions in managing fusarium. Cereals also vary in their susceptibility: durum is highly susceptible, barley is less susceptible than wheat and oats are the least susceptible cereal crop.
  2. Apply Fungicide When There Is an Elevated Risk Of FHB. The risk of fusarium infection increases when hot, humid or wet conditions persist during head emergence and flowering, taking as little as three days for infection to occur. Timely application of a foliar fungicide with a specialized nozzle or nozzle combination for maximum head coverage can help protect crops from FHB at these critical stages. The agricultural departments in each province have relevant material on their websites, including risk maps, and producers are encouraged to make use of the provincial specific materials available.
  3. Plan Crop Rotations to Manage Fusarium. Fusarium can overwinter in crop stubble, so planning crop rotations that allow adequate time for residues to decompose before returning to cereal crops is crucial. Rotate away from cereal crops for at least one, and preferably two, years on fields that were recently affected by FHB.
  4. Plant clean seed and consider a seed treatment in high-risk areas to improve the crop stand. Always use clean seed that is low in fusarium (0% to 5% depending on provincial regulations) to reduce the potential for seedling blight. Applying a fungicide seed treatment can improve seedling germination and vigour in areas under pressure from FHB.
  5. Use a Combination of Best Management Practices to Control Fusarium. Using as many best management practices as possible provides the best chance to limit the spread and severity of fusarium outbreaks. Growing disease resistant varieties, applying fungicides, rotating crops and using clean, treated seed may have the highest impact.

Other options include timing crop development to escape the disease, management of crop residues to facilitate the breakdown of disease infectious structures, establishing a strong stand by using high quality, vigorous seed and appropriate seeding rates and avoiding irrigating during flowering.

By managing fusarium in the field, growers are keeping marketing options open for cereal grains.