Fusarium head blight (FHB) is a fungal disease of cereal crops, recognized by premature bleaching and salmon-coloured fungal growth on the heads of crops it has infected. FHB reduces yields, decreases grain quality and may limit crop marketing opportunities.
When FHB infects cereal crops, it can produce mycotoxins such as deoxynivalenol (DON), also commonly known as vomitoxin. As most importing countries have strict limits on DON levels, the presence of DON restricts the grain’s end uses and marketing potential. Shipments that exceed acceptable levels of DON could be rejected at tremendous cost to the industry and may impact Canada’s reputation as a producer of high-quality cereal grains.
To help keep marketing options open for your harvested grain and maximize your return on investment, Keep it Clean recommends the following practices to manage FHB:
- 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.
- Grow the most FHB-resistant varieties available in areas at risk for FHB. Growing resistant varieties is one of the most important decisions in managing the disease. Cereals also vary in their susceptibility: durum is the most susceptible to FHB, barley is less susceptible than wheat, and oats are the least susceptible cereal crop.
- Plant clean seed and consider a seed treatment in high-risk areas. Establish a strong stand by using high quality, vigorous seed and appropriate seeding rates. If possible, time crop development to escape the disease.
Scout for stage, not symptoms, and 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. Make use of the provincial specific materials available, including risk maps, to help assess risk and inform your decisions.
During the summer months, risk maps for the Prairie provinces can be found here:
If FHB is identified, send samples of harvested grain for testing to detect the presence of mycotoxins. Mycotoxins, such as DON, can limit the end-use of your harvested grain. Contact your grain buyer to discuss your marketing options.
At harvest, use a higher combine wind speed to help to separate the lighter, damaged kernels. Finely chop straw and chaff, spreading it evenly to accelerate break-down. Be sure to thoroughly clean all equipment before moving to an uninfected field.
- Rotate away from cereals on FHB-infected fields for 1–2 years to allow ample time for residue to decompose.
- 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 and rotating crops may have the highest impact.
Managing disease pressures is one of 5 Simple Tips to keep your crops ready for market. By limiting the spread and severity of FHB in the field, you can protect your investment and help keep marketing options open for cereal grains.