IDENTIFICATION OF FUSARIUM GRAMINEARUM TRAITS THAT RELATE TO MALT QUALITY DEFECTS AND FUSARIUM SUCCESS WITHIN THE MALT MICROBIOME

Fusarium head blight (FHB) is a devastating disease of barley which negatively impacts malting
quality. Unlike most other commodities that are affected by FHB, in malting barley there can also be
new pathogen growth and new production of mycotoxins after harvest, due to the suitable conditions
afforded by the malting environment. A field study was conducted in 2018 and 2019 at Brandon, MB
using barley varieties of different FHB resistance levels: AAC Goldman (moderately resistant) and
Newdale (moderately resistant to moderately susceptible). Barley plants were grown under irrigation and
plots were inoculated with single strain conidial suspensions using 7 different Fusarium graminearum
strains, plus a non-inoculated control. The study demonstrated differential response between the
varieties, with AAC Goldman displaying lower FHB severity in both years. Results from 2019 indicated
that AAC Goldman also presented lower fungal load and lower deoxynivalenol content, compared to
Newdale. The F. graminearum isolates will be categorized according to hydrophobin production type
and production rate. The potential of these hydrophobins to induce gushing in beer will be examined.
Barley harvested from the field experiment, infested individually with each pathogen strain, will be
micro malted. In the final malt, the F. graminearum density, deoxynivalenol concentration, hydrophobin
content, and malt quality parameters will be assessed, and the microbiome will be profiled. We expect
that the results from this project will lead to the development of new approaches to mitigating Fusarium
growth during malting.