Abstract Detail

Host/Plant Pathogen Interactions and Plant Health Management

Missihoun, D. Tagnon [1], Kotchoni, O. Simeon [2], Wei, Yangdou [1], Bonham-Smith, Peta [1].

Use of Brachypodium distachyon as a non-host species to find resistance against clubroot disease in Brassicaeae.

Clubroot, caused by Plasmodiophora brassicae, has emerged as a serious threat to the production of Brassica root vegetables and canola worldwide. The pathogen has a complex life cycle comprised of three major stages: survival in the soil as resting spores, primary infection of root hairs, and secondary infection followed by the development within the root cortex and the vascular cylinder of resting spores to be released into the soil. The pathogen causes galls to form on the roots of infected plants, restricting the flow of water and nutrients from roots to aboveground plant tissues, ultimately resulting in premature death of the plant and yield penalty. Previous research aimed at identifying clubroot resistance genes have focused on susceptible species of Brassicaceae, however, no resistance gene has been identified that can protect susceptible plants against all known P. brassicae pathotypes. We are therefore investigating the use of a nonhost species to identify more durable resistance genes. By using both light and electron microscopy, we have established that B. distachyon is a non-host species for P. brassiceae that does not succumb to disease progression. As with the two susceptible species, canola (Brassica napus) and Arabidopsis thaliana, B. distachyon has no defence against a primary infection by the pathogen, however, unlike the susceptible species, B. distachyon prevents secondary infection and subsequent establishment of clubroot. Similarly to infected susceptible species no hypersensitive response was observed in B. distachyon roots. Leveraging the B. distachyon complete genome sequence, we are now in the process of identifying the molecular basis of resistance to secondary infection by P. brassicae.

Related Links:
A highlight of the research project published in the magazine Top Crop Manager (November 2014).

1 - University of Saskatchewan, Department of Biology, 112 Science Place, Saskatoon, SK, S7N5E2, Canada
2 - Rutgers, The State University of New Jersey, Department of Biology, Center for Computational and Integrative Biology, Science Building Rm. 210, Camden, NJ, 08102, USA

Keywords:
Clubroot
Brachypodium distachyon
Canola
Non-host resistance.

Presentation Type: Poster:Posters for Topics
Session: P
Location: Hall D/The Shaw Conference Centre
Date: Monday, July 27th, 2015
Time: 5:30 PM
Number: PPA006
Abstract ID:98
Candidate for Awards:None