Disease

Canola leaf infected with Blackleg.

Canola disease issues are less prevalent and damaging than in other canola growing regions of the US and Canada, which receive summer rainfall. The light disease pressure is likely due to rotations and the Mediterranean climate typical of the inland Pacific Northwest. While canola acreage has expanded dramatically over the last decade the dryland production systems of eastern Washington continue to be dominated by wheat production allowing canola disease cycles to be broken. Additionally, the dry summers typical of the region decrease disease outbreak typical of other canola production regions. To preserve the state of low disease pressure it is important to continue rotating canola with other crops as the acreage of canola steadily increases.

  • Paulitz, T., S. Hulbert, E. Babiker, and K. Schroeder. 2013. Emerging Diseases of Canola and Camelina in the Pacific Northwest. In 2013 Dryland Field Day Abstracts: Highlights of Research Progress. Dept. of Crop and Soil Sciences Tech Report 13-1, WSU, Pullman, WA.
  • Paulitz, T., S. Hulbert, E. Babiker, and K. Schroeder. 2012. Canola and Camelina Diseases. In 2012 Dryland Field Day Abstracts: Highlights of Research Progress. Dept. of Crop and Soil Sciences Tech. Report 12-1, WSU, Pullman, WA.
  • Schroeder, K.L., T.C. Paulitz, and P.A. Okubara. 2009. Real-Time Detection and Quantification of Rhizoctonia and Pythium Species on the Cook Agronomy Farm. pp. 31-32. In: 2009 Dryland Field Day Abstracts: Highlights of Research Progress. Dept. of Crop and Soil Sciences Technical Report 09-1, WSU, Pullman.
  • Hulbert, S., E. Babiker, T. Paulitz, and K. Schroeder. 2008. Management of Rhizoctonia Damping-Off of Brassica Oilseed Crops in the PNW. In 2008 Field Day Abstracts: Highlights of Research Progress. Dept. of Crop and Soil Sciences Tech. Report 08-1, WSU, Pullman, WA.

Visit the Department of Crop and Soil Sciences site to see all the CSS Field Day Abstracts.

  • 2017 Annual WOCS Meeting
    • Washington Oilseed Cropping Systems Research 2016 (Diseases)
      Timothy Paulitz
  • 2017 Oilseed Workshop
    • Diseases in Brassica Oilseeds
      Tim Paulitz, USDA-ARS Pullman
  • 2015 PNW Oilseed and Direct Seed Cropping Systems Conference
    • Canola Diseases – Blackleg and Rhizoctonia
      Tim Paulitz, USDA-ARS, Pullman, WA
    • Diseases and Insect Pests of Canola
      Jim Davis, University of Idaho
  • 2013 Oilseed Production and Marketing Conference
    • Canola Diseases
      Kurt Schroeder, assistant plant pathologist, USDA-ARS Pullman
  • 2012 Oilseed Crop Production Workshop
    • Canola Diseases
      Timothy Paulitz, USDA-ARS Pullman

Black Leg

Canola left infected with Blackleg.

Blackleg is a disease of canola and other Brassica species caused by the fungus Leptosphaeria maculans, also commonly called Phoma lingum. It can be a serious disease of canola and can cause significant yield losses in susceptible varieties.

  • Paulitz, T.C., A.J. Knerr, D. Schlatter, K.E. Sowers, M.L. Derie, and L.J. du Toit. 2016. A Survey of Eastern Washington State for Blackleg Disease of Canola Caused by Leptosphaeria maculans and Leptosphaeria biglobosaIn 2016 Dryland Field Day Abstracts: Highlights of Research Progress. Dept. of Crop and Soil Sciences Tech Report 16-1, WSU, Pullman, WA.
  • Sowers, K., T. Paulitz, J. Davis, L. du Toit, K. Schroeder, and D. Wysocki. 2015. Blackleg in Canola: Reason for Alarm in Washington State?. In 2015 Dryland Field Day Abstracts: Highlights of Research Progress. Dept. of Crop and Soil Sciences Tech Report 15-1, WSU, Pullman, WA.

Visit the Department of Crop and Soil Sciences site to see all the CSS Field Day Abstracts.

  • 2018 Oilseed Workshop
    • Fungicide Timing and Rate to Control Blackleg Disease in Winter Canola
      Don Wysocki, Oregon State University

White Mold

Extension Publications

Cover of FS188E.

Sclerotinia Stem Rot or White Mold of Canola (Oilseed Series)

Sclerotinia stem rot (Sclerotinia sclerotiorum), also known as white mold, can be a very destructive disease of canola. In the canola-producing areas of Canada’s prairie provinces, as well as the midwestern and southern United States, Sclerotinia can be a major issue. Although the occurrence of Sclerotinia in the Pacific Northwest is minimal, it can cause extensive damage in infected fields.

For more information on disease contact:

Tim Paulitz
Phone: 509-335-7077
timothy.paulitz@usda.gov