|KEMP, NATHAN - ORISE FELLOW|
|BAKKER, MATTHEW - UNIVERSITY OF MANITOBA|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 12/7/2020
Publication Date: 12/11/2020
Citation: Vaughan, M.M., Kemp, N., Whitaker, B.K., Bakker, M.G., McCormick, S.P. 2020. Identification of a bacterial-fungal association that silences Fusarium graminearum virulence [abstract].
Technical Abstract: Fusarium graminearum (Fg) is the primary fungal pathogen responsible for Fusarium head blight (FHB), a devastating disease of wheat and barley worldwide. Bacterial-fungal associations can have considerable influence on the pathogenicity of fungi and shape the outcomes of plant-fungal interactions. Genome sequencing analysis revealed a Fg strain, 47556+, heavily contaminated with a bacterial symbiont that was identified as Paenibacillus illinoisensis. The bacteria appeared to have an ectosymbiotic association with the fungus because the rod-shaped bacterial cells were visible on the Fg 47556+ hyphae. Furthermore, the bacterial association could be eliminated by antibiotic treatment or repeatedly washing the fungal hyphae in a dilute tween solution over a filter large enough to allow bacteria cells through but not the hyphae. In comparison to the cured Fg strain (47556cured), 47556+ caused on average 70% less FHB symptoms and produced 80% less DON on wheat (cultivar Apogee). However, the association and phenotype of reduced pathogenicity and DON production could not be reconstituted by simply mixing the bacteria back with the cured Fg strain.