Detection of Plasmodiophora brassicae by Using Polymerase Chain Reaction

PCR을 이용한 Plasmodiophora brassicae의 검출

DNA amplification by polymerase chain reaction (PCR) was used to specifically detect Plasmodiophora brassicae, causing clubroot of crucifers. On the basis of DNA sequence informations, an oligonucleotide primer set specific for the pathogen was designed form small subunit gene (18S-like) and internal transcribed spacer (ITS) region of ribosomal DNA. Primer ITS 5/PB-C produced an amplification product of approximately 520 bp in length with DNA from P. brassicae. However, no amplification product was produced with DNAs from several soil-borne fungi, Didymella bryoniae and Rhizopus stolonifer. Using these primers, the clubroot pathogen was readily detected from infected roots of crucifers, but not from healthy roots. Southern hybridization analysis further confirmed that the amplification product was originated from P. brassicae.