Insects and Diseases PS&C Prairie Soils & Crops Journal

Individual management options are unlikely to fully protect crops from FHB, therefore multiple strategies (varietal resistance, rotation, and fungicide application) provide the best means of maintaining yield potential, reducing the risk of mycotoxin contamination, protecting quality, and enhancing producer returns. Background Fusarium head blight (FHB) continues to be one of the most serious diseases affecting cereal crops, especially in the eastern Canadian prairies. Losses to the Canadian grain industry during the 1990s totalled US$200 million for Ontario and Quebec and US$300 million for Manitoba1 (Windels, 2000). Yields and grain quality are reduced and the potential contamination of grain by mycotoxins, predominantly the trichothecene, deoxynivalenol (DON), is a constant threat to domestic and export markets2 (Gilbert and Tekauz, 2000). Symptoms of the disease are usually distinctive and can be easily recognised in the field (Fig. 1). Several Fusarium species cause FHB. The predominant species in North America is Fusarium graminearum Schwabe [teleomorph: Gibberella zeae (Schwein.) Petch], especially on wheat. More than 90 % of the isolations from Fusarium-damaged kernels are F. graminearum in Manitoba3 (Gilbert et al.