Impacts of Molecular Diagnostic Technologies on Plant Disease Management.
Detection and diagnosis of plant viruses has included serological laboratory tests since the 1960s. Relatively little work was done on serological detection of plant pathogenic bacteria and fungi prior to the development of ELISA and monoclonal antibody technologies. Most applications for laboratory-based tests were directed at virus detection with relatively little emphasis on fungal and bacterial pathogens, though there was some good work done with other groups of plant pathogens. With the advent of molecular biology and the ability to compare regions of genomic DNA representing conserved sequences, the development of laboratory tests increased at an amazing rate for all groups of plant pathogens. Comparison of ITS regions of bacteria, fungi, and nematodes has proven useful for taxonomic purposes. Sequencing of conserved genes has been used to develop PCR-based detection with varying levels of specificity for viruses, fungi, and bacteria. Combinations of ELISA and PCR technologies are used to improve sensitivity of detection and to avoid problems with inhibitors or PCR often found in plants. The application of these technologies in plant pathology has greatly improved our ability to detect plant pathogens and is increasing our understanding of, their ecology and epidemiology.
Martin
Robert R
RR
USDA-ARS Horticulture Crops Research Laboratory, 3420 NW Orchard Avenue, Corvallis, Oregon 97330; e-mail: martinrr@ava.bcc.orst.edu.
James
Delano
D
Centre for Plant Health, Canadian Food Inspection Agency, 8801 East Saanich Road, Sidney, British Columbia V8l 1H3, Canada; e-mail: jamesd@em.agr.ca.
Lévesque
C André
CA
Eastern Cereal and Oilseed Research Center (ECORC), Agriculture and Agri-Food Canada, 960 Carling Avenue, Ottawa, Ontario K1A OC6, Canada; e-mail: levesqueca@em.agr.ca.