The present invention relates to a Brassica plant, in particular a Brassica oleracea plant carrying a genetic determinant that comprises QTL1 and/or QTL2, which confer resistance against Plasmodiophora brassicae, and which genetic determinant is present in plants that are grown from seeds which were deposited with the NCIMB under NCIMB accession number 41851. The present invention further relates to a nucleic acid molecule causative of resistance against Plasmodiophora brassicae, comprising a DNA sequence, which is linked to marker BO00812 (SEQ ID No.1) located on chromosome 3, in particular located on chromosome 3 between marker BO00365 (SEQ ID No. 3) and marker BO00403 (SEQ ID No. 4), or a DNA sequence, which is linked to marker BO001026 (SEQ ID No.2) located on chromosome 8, in particular located on chromosome 8 between marker BO00829 (SEG ID No. 5) and marker BO01007 (SEQ ID No. 6).