title: Specific and Sensitive Detection of Venturia nashicola, the Scab Fungus of Asian Pears, by Nested PCR.
abstract: The fungus Venturia nashicola is the causal agent of scab on Asian pears. For the rapid and reliable identification as well as sensitive detection of V. nashicola, a PCR-based technique was developed. DNA fingerprints of three closely related species, V. nashicola, V. pirina, and V. inaequalis, were obtained by random amplified polymorphic DNA (RAPD) analysis. Two RAPD markers specific to V. nashicola were identified by PCR, after which two pairs of sequence characterized amplified region (SCAR) primers were designed from the nucleotide sequences of the markers. The SCAR primer pairs, designated as D12F/D12R and E11F/E11R, amplified 535-bp and 525-bp DNA fragments, respectively, only from genomic DNA of V. nashicola. The specificity of the primer sets was tested on strains representing three species of Venturia and 20 fungal plant pathogens. The nested PCR primer pair specific to V. nashicola was developed based on the sequence of the species-specific 525-bp DNA fragment amplified by primer set E11F/E11R. The internal primer pair Na11F/Na11R amplified a 235-bp fragment from V. nashicola, but not from any other fungal species tested. The nested PCR assay was sensitive enough to detect the specific fragment in 50 fg of V. nashicola DNA.
authors.affiliation: Department of Biology, Sunchon National University, Suncheon 540-950, Korea.
authors.forename: Hyun Seok
authors.initials: HS
authors.lastname: Koh
authors.affiliation: Department of Biology, Sunchon National University, Suncheon 540-950, Korea.
authors.forename: San Ho
authors.initials: SH
authors.lastname: Sohn
authors.affiliation: Department of Biology, Sunchon National University, Suncheon 540-950, Korea.
authors.forename: Young Sun
authors.initials: YS
authors.lastname: Lee
authors.affiliation: Department of Plant Medicine, Sunchon National University, Suncheon 540-950, Korea.
authors.forename: Young Jin
authors.initials: YJ
authors.lastname: Koh
authors.affiliation: Pear Research Station, National Institute of Horticultural & Herbal Science, Naju 520-820, Korea.
authors.forename: Jang Hoon
authors.initials: JH
authors.lastname: Song
authors.affiliation: Department of Biology, Sunchon National University, Suncheon 540-950, Korea.
authors.forename: Jae Sung
authors.initials: JS
authors.lastname: Jung
keywords: Asian pear; SCAR; Venturia nashicola; nested PCR; pear scab