The rapid and sensitive detection of plant pathogens by molecular methods

A range of molecular methods is available for detecting specific components of pathogens in plant material. Of these, the detection of antigenic proteins by immunological methods is rapid and inexpensive. The detection of genome components by nucleic acid based technologies, although more complex, is approaching the simplicity of immunological methods with the advantage of greater sensitiwty and specificity. The latter techniques are suitable for most pathogens, but are particularly relevant for non-immunogenic pathogens, such as viroids, and for applications where sensitivity of detection must be at least as high as for current biological diagnoses, such as in quarantine situations. Nucleic acid component analysis can also be used for investigations of diseases of unknown etiology. In an overview, available techniques relevant to plant pathology are briefly described and compared .