HO/LL canola with resistance to clubroot disease

A method for identifying a clubroot resistant plant comprising a mutation in a fad3 gene contributing to a low linolenic acid phenotype in Brassica napus, the method comprising:

• isolating genomic DNA comprising a clubroot resistance gene from a plant;
• determining the presence in the isolated genomic DNA of a polynucleotide that is amplified in a polymerase chain reaction by the primers of SEQ ID NO:18 and SEQ ID NO:19 and is 300 nucleotides in length;
• and
• determining the presence in the isolated genomic DNA of a polynucleotide that is specifically hybridizable with the complement of SEQ ID NO:12, wherein the polynucleotide comprises a single nucleotide polymorphism (SNP) nucleic acid molecular marker that is an adenine at the position corresponding to the first base of a 5′ splice site in the third intron of the Brassica napus fad32 gene contributing to a low linolenic acid phenotype in Brassica napus.