Chemotypes of Fusarium graminearum isolates and accumulation of deoxynivalenol (DON), 15-ADON and 3-ADON in naturally infected and inoculated winter wheat in Ontario, Canada

Fusarium graminearum (Schwabe) causes Fusarium head blight (FHB), an important wheat disease. A shift in the presence of two F. graminearum chemotypes, 15-acetyl DON (15-ADON) and 3-acetyl DON (3-ADON) was identified in some part of North America (Ward et al. 2008). F. graminearum isolates collected from winter wheat in Ontario are mainly of the 15-ADON chemotype (Tamburic-Ilincic et al. 2006). Deoxynivalenol (DON) is the most important mycotoxin produced by F. graminearum; 15-ADON and 3-ADON analogs may also be produced. In the first study the objectives were to identify Fusarium species and to measure level of DON from commercial wheat fields in Ontario from 2004 to 2007 and level of 15-ADON and 3-ADON from fields in 2007. In the second study, the objective was to compare level of DON and the analogs produced after wheat cultivars were spray-inoculated with 15-ADON and 3-ADON isolates of F. graminearum.