Genomic variability in Potato virus M and the development of RT-PCR and RFLP procedures for the detection of this virus in seed potatoes | Xu et al. Virology Journal 2010 7 25 http content 7 1 25 VIROLOGY JOURNAL RESEARCH Open Access Genomic variability in Potato virus M and the development of RT-PCR and RFLP procedures for the detection of this virus in seed potatoes Huimin Xu Jeanette D Aubin Jingbai Nie Abstract Potato virus M PVM Carlavirus is considered to be one of the most common potato viruses distributed worldwide. Sequences of the coat protein CP gene of several Canadian PVM isolates were determined. Phylogenetic analysis indicated that all known PVM isolates fell into two distinct groups and the isolates from Canada and the US clustered in the same group. The Canadian PVM isolates could be further divided into two sub-groups. Two molecular procedures reverse transcription - polymerase chain reaction RT-PCR and restriction fragment length polymorphism RFLP were developed in this study for the detection and identification of PVM in potato tubers. RT-PCR was highly specific and only amplified PVM RNA from potato samples. PVM RNAs were easily detected in composite samples of 400 to 800 potato leaves or 200 to 400 dormant tubers. Restriction analysis of PCR amplicons with MscI was a simple method for the confirmation of PCR tests. Thus RT-PCR followed by RFLP analysis may be a useful approach for screening potato samples on a large scale for the presence of PVM. Background Potato virus M PVM a member of the genus Carla-virus in the family Flexviridae has a single-stranded polyadenylated positive-sense genomic RNA of appropriately kb in length 1 2 . PVM is considered to be one of the most common potato viruses distributed worldwide and an economically important pathogen of potato Solanum tunerosum . PVM can cause a yield reduction in potatoes between 15 and 45 and potato cultivars may be 100 infected in some regions 3 . The virus is transmitted by aphids in a non- persistent manner and by mechanical inoculation with sap from young leaves 1 . PVM causes mottle mosaic .
