Evaluation of canola breeding lines with clubroot resistance

Using a combination of traditional breeding techniques, as well as new technologies, Agriculture and Agri-Food Canada has developed canola (Brassica napus) lines with novel clubroot resistance (CR). AAFC is making these lines available for evaluation under a material transfer agreement in anticipation of non-exclusive licensing.

Brassica napus BNCR-E01-1
Brassica napus BNCR-E01-2
Brassica napus BNCR-92-1
Brassica napus BNCR-92-2

Spring-type Brassica napus lines with introgressed resistance from B. rapa turnip show high levels of resistance to clubroot. Lines BNCR-92-1 and BNCR-92-2 were resistant to 90% of clubroot strains while lines BNCR-E01-1 and BNCR-E01-2 were resistant to all the 90 strains collected in western Canada.

Conventional breeding methods (interspecific crosses, backcrosses and microspore culture) were used for developing the breeding lines. Lines ECD01 and 96-6992 (turnip, clubroot-resistant, vegetables of B. rapa) were crossed with DH16516 (spring-type, clubroot-susceptible, canola-quality line of B. napus) to produce F1 progeny respectively. Backcrosses with DH16516 (recurrent parent) were performed to produce BC1 and BC2 populations. BC2 plants with resistance to clubroot were chosen as the donor for microspore culture to develop DH lines. Genotyping by sequencing was performed to confirm the presence of two clubroot resistance genes in lines BNCR-E01-1&2 and a cluster of clubroot resistance genes in lines BNCR-92-1&2.

The lines do not require vernalization for producing seed so it can grow normally in western Canada. In addition, the breeding lines can serve as clubroot resistant donors for oilseed rape (canola) breeding worldwide.

Brassica napus BN-R-TE
Brassica napus BN-R-TJ

BN-R-TE and BN-R-TJ re-synthesized B. napus lines with clubroot resistance from both A and C genomes were resistant to all the strains tested.

Conventional breeding methods (interspecific crosses and self-pollination), plant tissue culture (embryo rescue) and chromosome doubling were used for developing the breeding lines. Line T19 (turnip, clubroot-resistant, vegetable of B. rapa) carries clubroot resistance genes Rcr4, Rcr8 and Rcr9 while lines ECD11 (cabbage, clubroot-resistant, vegetable of B. oleracea) and JL04 (kale, clubroot-resistant, vegetable of B. oleracea) carry quantitative trait loci (QTL) resistant to clubroot. Interspecific crosses of T19 with ECD11 and JL04 respectively were made. The F1 plantlets (haploid) were treated with colchicine for chromosome doubling to produce B. napus (doubled haploid). The re-synthesized B. napus plants were self-incompatible in F1. To obtain self seed, plants with open flowers and unopened buds were enclosed in an air-tight plastic bag and CO2 pumped into the bag to raise the internal concentration. Self-compatibility was improved after successive self-pollination until F4. The lines were highly resistant to all eight important clubroot strains tested.

The lines require vernalization for producing seed so they cannot grow naturally for seed production in western Canada. However, the lines can serve as clubroot resistant donors for canola breeding especially for introgression of clubroot resistance from C-genome into canola.

These lines can be obtained from AAFC for evaluation on a non-exclusive basis with the execution of a Material Transfer Agreement (MTA).

Upon evaluation, if a recipient under the MTA wishes to use or incorporate traits from a line(s) for the production of commercial varieties, a non-exclusive licence will be negotiated for its use and a one-time fee applied.

For further information:

Contact Keith Hanson (keith.hanson@agr.gc.ca), Office of Intellectual Property and Commercialization.