22 - 24 September 2009

Plant viruses pose a significant biosecurity threat to Australia’s agricultural industries. Current diagnostics range from symptom based analysis to nucleic acid assays and enzyme linked immunoassay (ELISA) detection of viral pathogens. Whilst ELISA tests are routinely used, it involves many manual handling steps and is limited to a single virus per test. New technologies are therefore required, we describe the next generation of ELISA-like diagnostics, the OptoPlex^TM bead-based immunoassay system for high throughput multiplexed screening for viruses in plant tissue. Three economically important potato viruses; Potato virus Y, Potato leafroll virus and Potato virus X are regularly tested for in certified potato seed schemes. An assay was developed to test for the three viruses in multiplex using the OptoPlex^TM system. The detection limits for all three viruses were found to be equivalent to that of single virus ELISA and reduced processing time, handling and reagent quantities. Work is continuing to broaden the assay to include more viruses in the Solanaceae and to target other commercially important crops.