Contribution of non-host crops of Plasmodiophora brassicae to clubroot management and inoculum potential

• Author / Creator

  Xiao, Qiang

• Clubroot, caused by Plasmodiophora brassicae Woronin, is a major soilborne disease of canola in Alberta. Root exudates from host (Chinese cabbage (Brassica rapa var. pekinensis, cv. Granaat), canola (Brassica rapa L.)) and non-host (perennial ryegrass (Lolium perenne L.)) plants were found to significantly stimulate germination of pathogen resting spores, suggesting that these plants could be used as bait crops to manage clubroot. In greenhouse studies, cropping of B. rapa L. canola and perennial ryegrass significantly reduced clubroot severity in a subsequent B. napus L. canola crop, but more research is needed before bait crops can be recommended for clubroot management. Secondary zoospores produced on ryegrass could infect canola, resulting in disease development and indicating that ryegrass could contribute to P. brassicae inoculum in the soil. The manipulation of seeding dates and cropping of resistant cultivars were also assessed as clubroot management tools and found to reduce the severity of disease. Sustainable management of clubroot of canola will likely require an integrated approach, incorporating various strategies.

• Graduation date

  Spring 2012

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3PP5V

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.