Reaction of selected Brassica vegetable crops to Canadian pathotypes of Plasmodiophora brassicae

Figures & data

Table 1.  Cultivar and seed source for the Brassica crops assessed and the predominant pathotype (P) of Plasmodiophora brassicae at each site (Muck Crops Research Station (MCRS), Crop Diversification Centre North (CDCN), Leduc, AB, and Bassano, AB)

	Site and pathotype
Crop and cultivar	MCRS (P6) (ECD 16/0/14)	CDCN (P5) (ECD 16/15/0)	Leduc (P3) (ECD 16/15/12)	Bassano (P5) (ECD 16/15/0)	Source
Broccoli (Brassica oleracea var. botrytis)
BC 7540 (R)^1	X^2				Sakata Seed Inc., CA
Diplomat (S)	X				Stokes Seeds Ltd.
Alborado F1 (na)		X	X		Bejo Seeds Inc., NY
Arcadia (na)		X	X		Seedway Inc.
Belstar F1 (na)		X	X		Bejo Seeds Inc.
Captain (na)		X	X		Semenis Inc., QC
Coronado F1 (na)		X	X		Bejo Seeds Inc.
Eureka (na)		X	X		Stokes Seeds Ltd.
Iron (na)		X	X		Semenis Inc.
Lucky F1 (na)		X	X		Bejo Seeds Inc.
Major (na)		X	X		Seedway Inc.
Surveyor (na)		X	X		Bejo Seeds Inc.
Premium Crop (na)		X	X		Seedway Inc.
Windsor (na)		X	X		Syngenta
Brussels sprouts (B. oleracea var. gemmifera)
Crispus (R)	X				Syngenta, ON
Jade Cross E (S)	X				Syngenta
Diablo (na)		X	X		Seedway Inc., PA
Oliver (na)		X	X		Stokes Seeds Ltd., ON
Spouket (na)		X	X		Norseco Ltd., QC
Canola (B. napus) and mustard (B. juncea)
Pennant (Mustard) (S)			X	X	Viterra, MB
45H26 (na)			X	X	Pioneer Hi-Bred., ON
45H29 (na)			X	X	Pioneer Hi-Bred., ON
9551 (na)				X	AAFC, AB
Green cabbage (B. oleracea var. capitata)
Kilaherb (R)	X				Stokes Seeds Ltd.
Kilaton (R)	X				Stokes Seeds Ltd.
Kilaxy (R)	X				Stokes Seeds Ltd.
Bronco (S)	X				Bejo Seeds Inc.
Blue Thunder (na)		X			Stokes Seeds Ltd.
Headstart (na)		X			Stokes Seeds Ltd.
Manoko (na)		X			Seedway Inc.
Optiko (na)		X			Seedway Inc.
Lennox (na)		X			Norseco Ltd.
Emblem (na)		X			Sakata Seed Inc.
Supreme Vantage (na)		X			Sakata Seed Inc.
Napa cabbage (B. rapa spp. pekinensis)
Bilko (R)	X	X			Stokes Seeds Ltd.
Mirako (S)	X	X			Bejo Seeds Inc.
Graanat (S)				X	Horticulture Research International, UK
Blues (na)		X			Stokes Seeds Ltd.
Kasumi (na)		X			Stokes Seeds Ltd.
Nikko (na)		X			Bejo Seeds Inc.
Joi Choi (na)		X			Seedway Inc.
Radish (Raphanus sativus)
Cherry Belle (na)		X		X	Norseco Ltd., QC
Crimson Giant (na)		X		X	Norseco Ltd., QC
French Breakfast (na)		X		X	Norseco Ltd., QC
Scarlet Globe (na)		X		X	Norseco Ltd., QC
Tillage Radish® (na)		X		X	Steve Groff Seeds, PA
Shanghai pak choy (B. rapa spp. chinensis var. communis)
Bejo 2834 (R)	X				Bejo Seeds Inc.
Mei Qing Choi (S)	X				Stokes Seeds Ltd.
Feng Qing Choi (na)			X		Sakata Seed Ltd.
^1Cultivars name denoted with ‘R’ represent resistant and ‘S’ susceptible to clubroot, and cultivars with unknown reactions to clubroot are marked as ‘na’.
^2X represents crop and cultivar used in particular sites.

Table 2.  Clubroot incidence (CI) and disease severity index (DSI), and marketable yield of Brassica crops and cultivars at the Muck Crops Research Station, ON (P6) (ECD 16/0/14) at sites with high and low levels of clubroot in 2011 and 2012

	2011			2012
	High			High			Low
Crop and cultivar	CI (%)^1	DSI (%)	Yield (kg/plant)	CI (%)	DSI (%)	Yield (kg/plant)	CI (%)	DSI (%)	Yield (kg/plant)
Bok/Pak choy
Bejo 2834	0± 5.9 c^2	0 ± 5.8 c	2.06 ± 0.7 a	0 ± 5.9 c	0 ± 2.8 d	1.51 ± 0.2 a	0 ± 11 e	0 ± 5.7 c	1.83 ± 0.4 a
Mei Qing Choi	100 ± 5.9 a	100 ± 5.8 a	0.83 ± 0.7 b	100 ± 5.9 a	80 ± 2.8 b	0.85 ± 0.2 b	13 ± 11 e	4 ± 5.7 c	1.24 ± 0.4 b
Broccoli
BC 7540	43 ± 5.9 b	14 ± 5.8 b	0.85 ± 0.3 a	78 ± 5.9 b	30 ± 2.8 c	0.66 ± 0.5 a	25 ± 11 d	8 ± 5.7 c	0.83 ± 0.6 a
Diplomat	100 ± 5.9 a	100 ± 5.8 a	0.11 ± 0.3 b	100 ± 5.9 a	100 ± 2.8 a	0.24 ± 0.5 b	88 ± 11 a	50 ± 5.7 a	0.83 ± 0.6 a
Brussels sprouts
Crispus	0 ± 5.9 c	0 ± 5.8 c	3.77 ± 2.1 a	0 ± 5.9 c	0 ± 2.8 d	0.31 ± 0.2 a	0 ± 11 e	0 ± 5.7 c	0.32 ± 0.3 b
Jade Cross	100 ± 5.9 a	100 ± 5.8 a	0.88 ± 2.1 b	100 ± 5.9 a	100 ± 2.8 a	0 ± 0.2 b	53 ± 11 c	24 ± 5.7 b	0.55 ± 0.3 a
Green cabbage
Kilaherb	0 ± 5.9 c	0 ± 5.8 c	2.56 ± 1.6 a	0 ± 5.9 c	0 ± 2.8 d	3.40 ± 1.4 a	0 ± 11 e	0 ± 5.7 c	4.08 ± 2.4 a
Kilaton	0 ± 5.9 c	0 ± 5.8 c	2.72 ± 1.6 a	−	−	−	−	−	−
Kilaxy	0 ± 5.9 c	0 ± 5.8 c	2.24 ± 1.6 a	−	−	−	−	−	−
Bronco	100 ± 5.9 a	100 ± 5.8 a	0.74 ± 1.6 b	100 ± 5.9 a	98 ± 2.8 a	0.68 ± 1.4 b	65 ± 11 b	26 ± 5.7 b	4.39 ± 2.4 a
Napa cabbage
Bilko	−	−	−	8 ± 5.9 c	3 ± 2.8 d	2.10 ± 0.3 a	3 ± 11 e	2 ± 5.7 c	2.37 ± 1.1 a
Mirako	−	−	−	100 ± 5.9 a	100 ± 2.8 a	1.44 ± 0.3 b	24 ± 11 d	10 ± 5.7 c	2.41 ± 1.1 a
^1Values are the means of four replications (20 plants per rep) ± SE.
^2Means followed by the same letter do not differ at P < 0.05 based on Tukey's test. Mean separation for yield was assessed within crop, but was assessed among cultivars for CI and DSI.

Table 3.  Clubroot incidence (CI) and disease severity index (DSI) of selected Brassica vegetables at Leduc, AB (pathotype 3) (ECD 16/15/12) in 2007

Crop and cultivar	CI (%)^1	DSI (%)
Broccoli
Surveyor	53 ± 7.4 c^2	33 ± 7.5 d
Coronado	58 ± 7.4 c	35 ± 7.5 d
Lucky	66 ± 7.4 bc	43 ± 7.5 bc
Alborado	70 ± 7.4 abc	48 ± 7.5 abc
Belstar	73 ± 7.4 abc	53 ± 7.5 abc
Iron	75 ± 7.4 abc	59 ± 7.5 abc
Eureka	79 ± 7.4 ab	56 ± 7.5 abc
Arcadia	80 ± 7.4 ab	56 ± 7.5 abc
Major	84 ± 7.4 a	62 ± 7.5 ab
Premium Crop	84 ± 7.4 a	66 ± 7.5 ab
Captain	91 ± 7.4 a	70 ± 7.5 a
Brussels sprouts
Diablo	80 ± 7 ns^3	59 ± 7.4 ns
Spouket	82 ± 7	60 ± 7.4
Oliver	83 ± 7	67 ± 7.4
Chinese cabbage
Bilko	12 ± 4.3 b	6 ± 4.8 b
Blues	90 ± 4.3 a	87 ± 4.8 a
Mirako	96 ± 4.3 a	94 ± 4.8 a
Nikko	100 ± 4.3 a	99 ± 4.8 a
Joichoi	100 ± 4.3 a	96 ± 4.8 a
Kasumi	100 ± 4.3 a	99 ± 4.8 a
Green cabbage
Headstart	98 ± 2.1 ns	93 ± 5.4 ns
Bluethunder	99 ± 2.1	92 ± 5.4
Lennox	99 ± 2.1	89 ± 5.4
Monoko	100 ± 2.1	98 ± 5.4
Optiko	100 ± 2.1	88 ± 5.4
Pak choy
Feng Qing Choi	100	100
^1Values are the means of four replications (100 plants per rep.) ± SE.
^2Means within a crop followed by the same letter do not differ at P < 0.05 based on Tukey's test.
^3ns, not significant.

Table 4.  Primary (%) and secondary infection (number of secondary plasmodia) of Brassica crops and cultivars by pathotypes 5 (P5) (ECD 16/15/0) and 6 (P6) (ECD 16/0/14) of Plasmodiophora brassicae under controlled conditions

	Primary infection (%)^1		Secondary infection (no. of secondary plasmodia)
Crop & Cultivar	P5	P6	P5	P6
Bok/Pak choy
Bejo 2834	56 ± 5.5 c^2	68 ± 3.4 d	14 ± 4.6 b	19 ± 2.3 b
Mei Qing Choi	81 ± 5.5 a	81 ± 3.4 a	22 ± 4.6 a	22 ± 2.3 a
Broccoli
BC 7540	81 ± 5.5 a	67 ± 3.4 d	22 ± 4.6 a	18 ± 2.3 b
Diplomat	61 ± 5.5 c	74 ± 3.4 b	14 ± 4.6 b	22 ± 2.3 a
Brussels sprouts
Crispus	74 ± 5.5 b	66 ± 3.4 d	19 ± 4.6 a	18 ± 2.3 b
Jade Cross	74 ± 5.5 b	72 ± 3.4 c	21 ± 4.6 a	21 ± 2.3 a
Napa cabbage
Bilko	43 ± 5.5 d	50 ± 3.4 e	10 ± 4.6 c	14 ± 2.3 c
Mirako	73 ± 5.5 b	79 ± 3.4 a	15 ± 4.6 b	19 ± 2.3 b
^1Values are the means of eight replications (one plant per rep) ± SE.
^2Means followed by the same letter in the column do not differ at P < 0.05 based on Tukey's test.

Fig. 1. Clubroot incidence (%) and severity (disease severity index) of the Brassica vegetables inoculated with field collected Plasmodiophora brassicae pathotypes 2 (ECD 16/15/31), 3 (ECD 16/15/12), 5 (ECD 16/15/0) and 6 (ECD 16/0/14) under controlled environment. Bars with the same letter above do not differ based on Tukey's test at P < 0.05. Capped lines represent ± SE.

Fig. 2. Clubroot reaction of cultivars of broccoli, Pak/Bok choy, Brussels sprouts and napa cabbage inoculated with Plasmodiophora brassicae pathotype 6 (ECD 16/0/14) under controlled environmental conditions.

Table 5.  Clubroot incidence (CI) and disease index severity (DSI) of canola and radish cultivars grown in clubroot-infested soil from two sites near Edmonton, AB (CDCN, pathotype 5 (P5) (ECD 16/15/0); Leduc, P3(ECD 16/15/12)) and soil-less mix inoculated with resting spores of P3 under controlled environmental conditions

	Clubroot Incidence (%)^2			DSI (%)
Crop and cultivar^1	CDCN	Leduc	Soil-less	CDCN	Leduc	Soil-less
Canola
45H26	55 ± 12.5 ns^3	50 ± 3.9 a^4	86 ± 6.9 a	45 ± 9.5 ns	42 ± 3.6 a	75 ± 5.9 a
45H29	26 ± 12.5	5 ± 3.9 b	29 ± 6.9 c	20 ± 9.5	4 ± 3.6 b	22 ± 5.9 c
Radish
Cherry Belle	19 ± 12.5	0 ± 3.9 b	44 ± 6.9 b	12 ± 9.5	0 ± 3.6 b	32 ± 5.9 b
Crimson Giant Champion	36 ± 12.5	0 ± 3.9 b	21 ± 6.9 c	24 ± 9.5	0 ± 3.6 b	16 ± 5.9 c
French Breakfast	38 ± 12.5	7 ± 3.9 b	45 ± 6.9 b	24 ± 9.5	7 ± 3.6 b	37 ± 5.9 b
Scarlet Globe	24 ± 12.5	0 ± 3.9 b	26 ± 6.9 c	14 ± 9.5	0 ± 3.6 b	17 ± 5.9 c
Tillage Radish®	14 ± 12.5	0 ± 3.9 b	0 ± 6.9 d	9 ± 9.5	0 ± 3.6 b	0 ± 5.9 d
^1No symptoms of clubroot developed in the non-infected controls.
^2Values are the means of six replications ± SE (one plant per rep).
^3ns, not significant.
^4Means followed by the same letter do not differ at P < 0.05 based on Tukey's test.