Development and deployment of novel resistance genes to improve clubroot management on canola

Key Result

This project is still in progress and aims to characterize previously identified clubroot resistance genes, including their modes of action in stacking, develop molecular markers and use pre-breeding and breeding processes to produce novel clubroot resistance resources.

Project Summary

This research aims to provide a comprehensive understanding of the most effective clubroot resistance deployment strategies to maximize resistance performance and longevity.

The information and resources developed in this project will facilitate adoption of novel clubroot resistance genes for resistance breeding, including optimal use of clubroot resistance genes in stacking or rotation. It will also work to enhance resistance durability. This will help maximize/optimize the utilization of genetic resources and foster sustainable clubroot management in canola production in western Canada.

Objectives

The specific project objectives are:

1a. Investigate B. napus genotypes carrying clubroot resistance genes originating from B. oleracea (C genome). Based on the understanding of C-genome resistance basis and develop molecular markers for clubroot resistance breeding.

1b. Identify and characterize novel clubroot resistance (CR) genes in unique B. napus sources and genetically map these clubroot resistance genes for development of resistance against newly identified Plasmodiophora brassicae races that are predominant on the Prairies.

2a. Develop near-isogenic lines carrying unique C-genome clubroot resistance genes for fine mapping of resistance, as well as for pyramiding clubroot resistance genes from A and C genomes against a wide range of P. brassicae pathotypes.

2b. Develop robust single nucleotide polymorphisms (SNP) markers tightly linked to the novel clubroot resistance genes to facilitate rapid incorporation of selected clubroot resistance genes into elite breeding canola lines.

3a. Understand the modes of action for two A-genome clubroot resistance genes, as well as their combinations, and a C-genome clubroot resistance gene using proteomics, metabolomics and synchrotron-based spectroscopy. Functional characterization of putative clubroot resistance genes and development of CRISPR-Cas9 tools will be carried out to validate these clubroot resistance genes against the C-genome gene.

3b. Understand modes of action for A-genome clubroot resistance genes, both singly and in combinations, using multiomics. Development of CRISPR-Cas9 tools will be carried out to validate the effectiveness of resistance functions of AAFC developed clubroot resistance resources.

4. Introgress clubroot resistance genes identified in the A and C genomes into specialty B. napus cultivars for production in high-risk clubroot areas on the Prairies.

5. Develop genomic data to better understand clubroot resistance evolution based on deep sequencing and on de novo genome assemblies for clubroot resistance using B. rapa, B. oleracea and B. napus accessions with abundant clubroot resistance loci. This information will reveal the relatedness of a variety of clubroot resistance genes, which may also help meaningful labelling of clubroot resistance genes in canola cultivars.

6. Investigate clubroot resistance durability, considering various strategies such as clubroot resistance gene stacking and rotation, in the context of intensive canola production.