The application of spot hybridization to the detection of DNA and RNA viruses in plant tissues.

A solid-phase nucleic acid hybridization technique for the detection of DNA and RNA viruses in plant tissues is described. The method involves spotting crude samples onto nitrocellulose and using 12P-labelled DNA hybridization probes. The limit of sensitivity is 5-20 pg virus/spot or approximately 5 micrograms/g leaf tissue. The method is quantitative for DNA viruses in crude homogenates, but not for RNA viruses. The amount of cauliflower mosaic virus in infected leaves and protoplasts was estimated. The amplitude of spot hybridization to screening plant material from glasshouses and field is discussed.