Page 50 - TriSociety Virtual Event

Abstracts

0C6, Canada; (A.F.) Charlottetown Research and Fusarium Head Blight (FHB) is a de vastating P. brassicae have emerged that can overcome
Development Centre, Agriculture and Agri-Food disease in Western Canada that afects both 1 generation resistance and are found in
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Canada, 400 University Avenue, Charlottetown, the quantity and qualitity of wheat grain an increasing number of fields In response
PE C1A 4N6, Canada. mainly due to mycotoxin contamination canola breeders have de veloped a new set
(deoxynivalenol­DON and nivalenol­NIV) of cultivars with so­called '2 generation'
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Fusarium head blight (FHB) is one of the most Fusarium graminearum is the principal cau­ resistance While the nature of this resistance
damaging diseases of barley FHB is caused by sative agent associated with FHB of wheat in is not in the public domain and may difer
a species complex that includes diferent Fu­ Western Canada Wheat spikes were collected among cultivars from diferent companies it
sarium spp and Fusarium graminearum is the in 2020 from an area not treated with fungicide is believed to be distinct from 1 generation
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species of greatest concern for FHB of barley in in 65 participating farmers' fields in Western resistance and is either conferred by a dife­
Canada Field sur veys show that two or more Canada to evaluate the presence of Fusarium rent resistance gene(s) or represents stacked
FHB species ofen co­exist within the same species and their chemotypes Inoculum resistance genes Studies are under way to
field or grain sample and currently F. poae availability was measured by setting up spore characteriZe the virulence of P. brassicae
has been reported as another dominant FHB traps in each field from flowering until the sof populations on diferent hosts with 2 gene­
nd
species in barley growing regions The aim of dough stage Both grain and chaf from spring ration resistance Isolations of the pathogen
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this study is to understand the pathogenicity wheat were sub ected to mycotoxin testing by were made from symptomatic 2 generation
of F graminearum F poae and mixture of high sensitive 5/5 Vomitoxin kits from Neogen CR canola crops identified in the field and
both species in co­inoculation causing FHB in and fungal species and chemotype testing by tested for their virulence on a suite of eight
barley under control condition Spray inocula­ DNA­based methods (PCR) The initial DON commercial canola cultivars carr ying 2 nd ge­
tion was performed on two susceptible barley testing showed that the 2020 growing season neration resistance These cultivars were also
genotypes at 10 to 14 days afer heading experienced mild levels of FHB toxin contami­ tested with selected P. brassicae pathotypes
Heads were assigned a visual FHB rating on nation In spring wheat the highest mean DON that break 1 generation resistance Prelimi­
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a scale of 0­9 at 4 7 14 21 and 28 days afer content was recorded from Manitoba samples nar y results indicate that about half of these
inoculation There was a significant diference (0 3 ppm in grain and 2 12 ppm in chaf ) while cultivars developed moderate to severe levels
in FHB symptoms between F. graminearum both Saskatchewan and Alberta samples con­ of clubroot when challenged with pathotypes
and F. poae with F. graminearum being the tained average DON levels <0 2 ppm in grain that can overcome 1 generation resistance
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most pathogenic species F. poae was least pa­ and <1 00 ppm in the chaf The chaf contai­ This suggests that resistance­breaking strains
thogenic and not statistically diferent than the ned a significantly higher DON le vel than the of P. brassicae may be dificult to control with
control treatment (inoculated with deioniZed grain suggesting that chaf removal during resistance alone
water only) When heads were co­inoculated harvest can reduce the impact of DON on the
with the mixture of both FHB species FHB grain The total genomic DNA was extracted Session 15. Regular author oral
symptoms were lower than the F. graminea­ from 24 Fusarium damaged kernels and �0 5 g presentations: Plant and Soil
rum treatment indicating that the presence of chaf from each spring wheat sample Dife­
of F. poae may reduce the pathogenicity of F. rent Fusarium species including F graminea­ health
graminearum. rum and their chemotype­producing genes
will be identified by 24 species ­specific PCR 78. Trends in symbiotic nitrogen fixation
76. Fusarium Head Blight species diver­ assays and presented over 100 years of soybean breeding
sity and deoxynivalenol (DON) levels in M S THILAKARATHNA D TORKAMANEH R W
Western Canadian producer wheat fields 77. The virulence of Plasmodiophora BRUCE I RAJCAN G CHU C M GRAINGER K
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S K KANNANGARA P BULLOCK S brassicae on canola with ‘2 generation’ SZCZYGLOWSKI B HILL AND M N RAIZADA
WALKOWIAK AND W G D FERNANDO Depart­ clubroot resistance Department of Agricultural, Food and Nutri­
ment of Plant Science, University of Manitoba, K HOLLMAN V P MANOLII S F HWANG AND tional Science, University of Alberta, 116 St & 85
222 Agriculture Building, 66 Dafoe Road, S E STRELKOV Department of Agricultural, Avenue, Edmonton, AB T6G 2R3, Canada; (D.T)
Winnipeg, R3T 2N2, Manitoba, Canada; (P.B.) Food and Nutritional Sciences, University of Département de Phytologie, Université Laval,
Department of Soil Science, University of Mani­ Alberta, Edmonton, AB T6G2P5, Canada. Pavillon Paul-Comtois 2425, rue de l’Agriculture,
toba, 362 Ellis Building, 13 Freedman Crescent, Québec QC G1V 0A6 Canada; (R.W.B., I.R., G.C.,
Winnipeg, R3T 2N2, Manitoba, Canada; (S.W.) Clubroot caused by Plasmodiophora brassi­ C.M.G, M.N.R) Department of Plant Agriculture,
Grain Research Laboratory, Canadian Grain cae is a damaging soilborne disease of canola Crop Science building, 50 Stone Road E. Guelph,
Commission, 196 Innovation Dr, Winnipeg, R3T (Brassica napus) first identified on the Cana­ Ontario, N1G 2W1 Canada; (K.S.) Agriculture
6C5, Manitoba, Canada; (W.G.D.F) Department dian Prairies in 2003 Clubroot resistant (CR) and Agri-Food Canada, London Research and
of Plant Science, University of Manitoba, 222 canola cultivars carr ying what is now known Development Centre, 1391 Sandford St, London,
Agriculture Building, 66 Dafoe Road, Winnipeg, as '1 generation' resistance were introdu­ ON, N5V 4T3 Canada; (B.H) Agriculture and
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R3T 2N2, Manitoba, Canada. ced in 2009­10 and soon became the most Agri-Food Canada, Lethbridge Research and
efective and widely used clubroot manage­ Development Centre, 5403 1 Ave S, Lethbridge,
ment tool Unfortunately new pathotypes of AB T1J 4B1, Canada.

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