Detection ofLeptosphaeria korraewith the polymerase chain reaction and primers from the ribosomal internal transcribed spacers

摘要

Leptosphaeria korrae, the causal agent of necrotic ring spot, is a destructive patch disease of Kentucky bluegrass. To develop a rapid molecular test for the detection of this pathogen, an assay based on the polymerase chain reaction (PCR) was developed utilizing the internal transcribed spacer region 1 (ITS 1) ofL.korraeribosomal DNA. DNA sequence comparison showed 94.8% similarity of the ITS 1 region amongL.korraeisolates and only 45–50% similarity betweenL.korraeand other fungal species. Based on ITS 1 sequence differences, a pair of oligonucleotide primers, LK17S and 5.8SC, were selected. With PCR, the primers specifically amplifiedL.korraeDNA and did not amplify DNA isolated from 15 other fungal species or healthy Kentucky bluegrass. The assay could also specifically detectL.korraein diseased turfgrass samples.Key words: detection, ITS 1,Leptosphaeria korrae, necrotic ring spot, polymerase chain reaction, ribosomal DNA.