European Journal of Plant Pathology

, Volume 145, Issue 3, pp 615–620 | Cite as

The gene Cr811 is present exclusively in pathotype 5 and new emerged pathotypes of the clubroot pathogen Plasmodiophora brassicae

  • Jie Feng
  • Junye Jiang
  • David Feindel
  • Stephen E. Strelkov
  • Sheau-Fang HwangEmail author


This study was conducted with the objective of finding genetic marker(s) to differentiate pathotypes of the clubroot pathogen Plasmodiophora brassicae. Ideally, such markers should be used as a diagnostic tool to identify or predict certain pathotypes. By using PCR with gene-specific primers, 117 non-housekeeping P. brassicae genes were investigated for their presence/absence in isolates representing pathotypes 2, 3, 5, 6 or 8 (Williams’ system), and in new strains of the pathogen recently identified from Alberta, Canada, which are highly virulent on clubroot resistant canola (Brassica napus) cultivars. One gene, named Cr811, was present in isolates of pathotype 5 and in a new strain of P. brassicae that also is classified as pathotype 5 on the system of Williams, but causes severe clubroot on resistant canola. Three additional newly identified virulent populations, similar to pathotype 3, also were tested and found to carry Cr811. In contrast, the Cr811 gene was absent in all isolates representing the original pathotypes 2, 3, 6 and 8. Quantitative real-time PCR analysis indicated greater copy numbers of Cr811 in the new virulent pathotype 3-like and pathotype 5-like populations versus the original pathotype 5, indicating a potential method to identify new pathotypes of P. brassicae before the breakdown of resistance could be detected in a canola crop. The association of Cr811 with infection by P. brassicae of previously resistant canola cultivars, as revealed by qPCR analysis, suggests that Cr811 plays an important role in the interaction between host resistance and P. brassicae pathogenicity.


Pathogenicity Virulence Resistance Pathotype Diagnosis Plastid 



The authors acknowledge the financial support from the Alberta Crop Industry Development Fund Ltd., the Canola Agronomic Research Program, the Growing Forward 2 Program (Agriculture and Agri-Food Canada/Canola Council of Canada), and the provincial canola grower groups including the Alberta Canola Producers Commission, SaskCanola, and the Manitoba Canola Growers Association.


  1. Bulman, S., Ridgway, H. J., Eady, C., & Conner, A. J. (2007). Intron-rich gene structure in the intracellular plant parasite Plasmodiophora brassicae. Protist, 158, 423–433.CrossRefPubMedGoogle Scholar
  2. Feagin, J. E. (1994). The extrachromosomal DNAs of apicomplexan parasites. Annual Review of Microbiology, 48, 81–104.CrossRefPubMedGoogle Scholar
  3. Feng, J., Hwang, S. F., & Strelkov, S. E. (2013a). Assessment of gene expression profiles in primary and secondary zoospores of Plasmodiophora brassicae by dot blot and real-time PCR. Microbiological Research, 168, 518–524.CrossRefPubMedGoogle Scholar
  4. Feng, J., Hwang, S. F., & Strelkov, S. E. (2013b). Studies into primary and secondary infection processes by Plasmodiophora brassicae on canola. Plant Pathology, 62, 177–183.CrossRefGoogle Scholar
  5. Howe, C. J. (1992). Plastid origin of an extrachromosomal DNA molecule from Plasmodium, the causative agent of malaria. Journal of Theoretical Biology, 158, 199–205.CrossRefPubMedGoogle Scholar
  6. Hwang, S. F., Strelkov, S. E., Feng, J., Gossen, B. D., & Howard, R. J. (2012). Plasmodiophora brassicae: a review of an emerging pathogen of the Canadian canola (Brassica napus) crop. Molecular Plant Pathology, 13, 105–113.CrossRefPubMedGoogle Scholar
  7. Jones, D. R., Ingram, D. S., & Dixon, G. R. (1982). Factors affecting tests for differential pathogenicity in populations of Plasmodiophora brassicae. Plant Pathology, 31, 229–238.CrossRefGoogle Scholar
  8. LeBoldus, J. M., Manolii, V. P., Turkington, T. K., & Strelkov, S. E. (2012). Adaptation to Brassica host genotypes by a single-spore isolate and population of Plasmodiophora brassicae [clubroot]. Plant Disease, 96, 833–838.CrossRefGoogle Scholar
  9. Manzanares-Dauleux, M. J., Barret, P., & Thomas, G. (2000). Development of a pathotype specific SCAR marker in Plasmodiophora brassicae. European Journal of Plant Pathology, 106, 781–787.CrossRefGoogle Scholar
  10. Sambrook, J., & Russell, D. W. (2001). Molecular cloning: a laboratory manual (3rd ed.). Cold Spring Harbor, NY: Cold Spring Harbor Laboratory Press.Google Scholar
  11. Schwelm, A., Fogelqvist, J., Knaust, A., Jülke, S., Lilja, T., Bonilla-Rosso, et al. (2015). The Plasmodiophora brassicae genome reveals insights in its life cycle and ancestry of chitin synthases. Scientific Reports, 5, 11153.CrossRefPubMedPubMedCentralGoogle Scholar
  12. Somé, A., Manzanares-Dauleux, M. J., Laurens, F., Baron, F., Thomas, G., & Rouxel, F. (1996). Variation for virulence on Brassica napus L. amongst Plasmodiophora brassicae collections from France derived from single-spore isolates. Plant Pathology, 45, 432–439.CrossRefGoogle Scholar
  13. Strelkov, S. E., & Hwang, S. F. (2014). Clubroot in the Canadian canola crop: 10 years into the outbreak. Canadian Journal of Plant Pathology, 36 (sup1), 27–36.Google Scholar
  14. Strelkov, S. E., & Hwang, S. F. (2016). Emergence of new virulence phenotypes of Plasmodiophora brassicae on canola (Brassica napus) in Alberta, Canada. European Journal of Plant Pathology, doi: 10.1007/s10658-016-0888-8.
  15. Strelkov, S. E., Manolii, V. P., Cao, T., Xue, S., & Hwang, S. F. (2007). Pathotype classification of Plasmodiophora brassicae and its occurrence in Brassica napus in Alberta, Canada. Journal of Phytopathology, 155, 706–712.CrossRefGoogle Scholar
  16. Strelkov, S. E., Manolii, V. P., Harding, M. W., Hwang, S. F., Fei, W., Rong, S., Burke, D. A., Pugh, C. A., Nielsen, J. M., Barnes, A., Jacobsen, C., Vadnais, M., & Feindel, D. (2015). The spread of clubroot on canola in Alberta in 2014. Canadian Plant Disease Survey, 95, 155–158.Google Scholar
  17. Strelkov, S. E., Tewari, J. P., Smith, E., & Smith-Degenhardt, E. (2006). Characterization of Plasmodiophora brassicae populations from Alberta, Canada. Canadian Journal of Plant Pathology, 28, 467–474.CrossRefGoogle Scholar
  18. Williams, P. H. (1966). A system for the determination of races of Plasmodiophora brassicae that infect cabbage and rutabaga. Phytopathology, 56, 624–626.Google Scholar
  19. Xue, S., Cao, T., Howard, R. J., Hwang, S. F., & Strelkov, S. E. (2008). Isolation and variation in virulence of single-spore isolates of Plasmodiophora brassicae from Canada. Plant Disease, 92, 456–462.CrossRefGoogle Scholar
  20. Zhang, H., Feng, J., Manolii, V. P., Strelkov, S. E., & Hwang, S. F. (2015). Characterization of a gene identified in pathotype 5 of the clubroot pathogen Plasmodiophora brassicae. Phytopathology, 105, 764–770.CrossRefPubMedGoogle Scholar

Copyright information

© Koninklijke Nederlandse Planteziektenkundige Vereniging 2016

Authors and Affiliations

  • Jie Feng
    • 1
  • Junye Jiang
    • 1
    • 2
  • David Feindel
    • 1
  • Stephen E. Strelkov
    • 2
  • Sheau-Fang Hwang
    • 1
    Email author
  1. 1.Crop Diversification Centre North, Alberta Agriculture and ForestryEdmontonCanada
  2. 2.Department of Agricultural, Food and Nutritional ScienceUniversity of AlbertaEdmontonCanada

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