Biotinylated nucleic acid hybridization probes for potato virus detection.

cDNA libraries, representative of potato viruses X (PVXc strain) and Y (PVY degrees strain) genomes were obtained. A PVX cDNA cloned fragment was sequenced and biotinylated to be used as hybridization probe for the detection of purified virus or nucleic acid extracts of infected plants. Dot hybridization assay was sensitive to detect 4 ng of viral particles, corresponding to about 200 pg of viral RNA. The level of detection in infected plant extracts was as effective as that obtained with the ELISA. The presence of biotinylated PVY cDNA in the hybridization mixture did not affect sensitivity of the PVX detection assay, suggesting that a single diagnostic assay for several potato viruses and virus-related pathogens could be developed.