Diagnostic Tools for Plant Biosecurity

There is now a wide range of diagnostic tools in the armoury to help prevent or control damaging disease outbreaks. When applied in the context of biosecurity, they have immense power to protect the plants on which food, feed, fuel and fibre supplies rely. Diagnoses which used to rely on culturing organisms, examining spores, or testing viruses on indicator plants, often taking many weeks to complete, can now be achieved in a matter of hours. Moreover, the advent of in-field diagnostic tests allows growers, agronomists or plant health and seeds inspectors to get a reliable test result without sending a sample to a laboratory. Remote sensing, using ground vehicles, unmanned aerial vehicles, or satellite technology, can bring a new dimension to surveillance, detection and diagnostic systems. Pathogen variation can be characterised rapidly by molecular marker techniques, potentially accelerating the process of identifying new pathotypes or fungicide resistant strains which threaten plant productivity. Metagenomic methods will undoubtedly play a part in non-targeted diagnostics, and identifying new threats to biosecurity. While diagnostic methods have advanced rapidly, their use in disease management in the field must be supported by robust sampling methods, treatment thresholds, and in depth understanding of disease risks.