A polymerase chain reaction assay adapted to plum pox potyvirus detection.

A sensitive, polyvalent assay based on the polymerase chain reaction (PCR) was developed for plum pox potyvirus (PPV) detection. This technique was adapted for a single tube, the chemical denaturation and reverse transcription of the viral RNA followed by the PCR reaction yielding a 243-base-pair product. As few as 10 fg of purified viral RNA, corresponding to approximately 2000 viral particles, were detected in plant extracts. All PPV isolates tested were amplified, and the amplified fragments were analysed by restriction endonuclease digestion. An RsaI restriction site polymorphism in the amplified fragments allowed the discrimination of two groups of isolates. In a field indexing trial, the PCR assay proved to be more sensitive than molecular hybridization using 32P-labelled RNA probes for PPV detection.