Page 205 - Plant Canada 2024 Proceeding

PLANT CANADA 2024

Abstracts for Poster Presentations

[P1] FIRST REPORT OF FUSARIUM SPOROTRICHIOIDES AND FUSARIUM CEREALIS CAUSING
ROOT ROT OF SOYBEAN IN CANADA, WITH POTENTIAL IMPLICATIONS FOR CROP ROTATION
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STRATEGIES. Ahmed Abdelmagid , Mohamed Hafez , and Fouad Daayf . Morden research and
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development center, 101 Rte 100 #100, Morden, MB R6M 1Y5; Agriculture and Agri-Food Canada,
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Lethbridge Research and Development Center, Lethbridge, Alberta T1J 4B1, Canada; Department of
Botany and Microbiology, Faculty of Science, Suez University, Suez 43518, Egypt; and Department of
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Plant Science, University of Manitoba, Winnipeg, Manitoba R3T2N2, Canada
Correspondence to: Ahmed.Abdelmagid@agr.gc.ca

Soybean plants exhibiting poor standing, stunting, and leaf chlorosis were collected from Manitoba fields
in 2017. Symptoms included few nitrogen-fixing nodules, reddish brown-to-black lesions on tap and
lateral roots, and cortical decay in roots and lower stems. Among 240 isolated strains, 5 were identified as
Fusarium sporotrichioides Sherb., and 12 as Fusarium cerealis based on morphology. A PCR-based
diagnostic test specifically targeted the trichothecene gene cluster in F. sporotrichioides, with primer
SPO1 amplifying a 541 bp fragment in fungal isolates from commercial soybean crops and artificially
infected roots. Trichothecene (TRI) gene expression was detected in infected soybean roots using RT-
PCR with TRI gene-specific primers. F. cerealis isolates were confirmed via sequencing the translational
elongation factor 1-alpha (TEF1) gene using universal primers EF1 and EF2. Under controlled conditions,
all isolates caused typical root rot symptoms in soybean, significantly reducing shoot and root length. The
pathogens were reisolated from infected plants and reidentified as F. sporotrichioides and F. cerealis as
mentioned above. This represents the inaugural report of F. sporotrichioides and F. cerealis as causal
agents of root rot in soybean within Canada. While these pathogens are commonly linked with Fusarium
head blight in cereals, their newfound ability to cause root rot in soybean underscores the importance of
understanding their broader impact. This finding may necessitate reconsideration of future crop rotation
strategies.

[P2] THE OCCURRENCE AND SPREAD OF CLUBROOT IN ALBERTA (2005-2023). Y. Aigu, V.P.
Manoli, S.F. Hwang, and S.E. Strelkov. Department of Agricultural, Food and Nutritional Science, 410
Agriculture/Forestry Center, University of Alberta, Edmonton, AB T6G 2P5, Canada
Correspondence to: yoann@ualberta.ca

Clubroot, caused by the obligate parasite Plasmodiophora brassicae, is a soilborne disease of canola
(Brassica napus) and other cruciferous hosts. Infection by P. brassicae is associated with the formation of
large galls on the roots of susceptible plants, leading to yield losses estimated at 10% to 15% globally. In
Alberta, Canada, clubroot was first identified on canola in 2003 and targeted surveys have been
conducted annually since 2005, generating a large data set. Since 2010, the disease has mainly been
managed by the planting of clubroot-resistant cultivars. However, in 2013, resistance-breaking
populations of P. brassicae were detected on canola in Alberta for the first time. The main objective of this
study was to characterize the spread of the clubroot pathogen, including the patterns and rates of
dissemination of non-resistance-breaking (NRB) and resistance-breaking (RB) populations of P.
brassicae. In the context of a mosaic of resistant and susceptible host genotypes, epidemiological
approaches were combined with geographical representation to enhance understanding of P. brassicae
dissemination, evaluate the efficacy of efforts to limit clubroot spread, and predict its further progress.
New cases of clubroot have been continuously detected every year. By 2023, clubroot had been identified
in nearly 4000 fields across Alberta. Isolates of P. brassicae from over 600 of those fields were
pathotyped using the Canadian Clubroot Differential set, with nearly 450 found to represent RB
populations.

[P3] CHARACTERIZATION OF EFFECTOR PbPE29: ITS POTENTIAL ROLE IN SUCCESSFUL
Plasmodiophora brassicae COLONIZATION OF Brassica napus L. (CANOLA). Cresilda V. Alinapon,
Chris D. Todd, and Peta C. Bonham-Smith. Department of Biology, 112 Science Place, University of
Saskatchewan, Saskatoon, SK, Canada S7N 5E2
Correspondence to: cresilda.alinapon@usask.ca

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