In 2014, winter wheat was impacted by fusarium head blight impacting both yield and quality. The FHB Index in 2014, as measured by the annual FHB Winter Wheat Survey, was 11.6%, higher than the 10-year average of 3.4% (see CropChatter post for complete report on survey at http://cropchatter.com/results-of-the-2014-fhb-winter-wheat-field-survey/).
High levels of infection were also recorded at the five Manitoba Crop Variety Evaluation Trials (MCVET). This provided an opportunity to evaluate how winter wheat varieties being tested post-registration by MCVET respond to fusarium head blight under non-misted conditions (natural infection) by measuring severity in-field, and assessing harvested samples for fusarium damaged kernels (FDK) and deoxynivalenol (DON) accumulation.
Composite samples of ten registered winter wheat varieties were collected from the three replicates at five MCVET sites: Arborg, Beausejour, Carberry, Isabella and Winnipeg. BioVision Seed Labs in Winnipeg, Manitoba conducted the analysis. The level of FDK (%) was measured as per the Official Grain Grading Guide of the Canadian Grain Commission. The accumulation of DON (ppm) was measured using the ELISA test method.
The variety Emerson, rated as Resistant (R), had lower levels of FDK and DON compared to the other varieties (see Figure 1) and consistently had lower visual symptoms or severity as expressed by the FHB Index (data not shown). Some varieties rated as Susceptible (S) consistently showed higher FHB severity, FDK and DON levels across all sites. However, data also shows there is variability of performance within the five resistance categories of Resistant (R) to Susceptible (S).
Figure 1: Average Levels of Fusarium Damaged Kernel (FDK) and Deoxynivalenol (DON) by Variety at Five MCVET Sites in 2014
To reduce the risk of fusarium head blight, producers should select varieties with improved resistance as the study indicates varieties with improved resistance generally had lower severity, FDK and DON levels. However, caution must be used with one year of data, as presented in this study. Using data derived over two or more growing seasons over multiple sites is always recommended to provide the best indicator of variety performance.
If interested in more information, please contact [email protected].
Submitted by: Pam de Rocquigny, Provincial Cereal Crops Specialist
Special thanks to the Manitoba Crop Variety Evaluation Team (MCVET) for providing funding and in-kind support.