New Virus Diagnostic Approaches to Ensuring the Ongoing Plant Biosecurity of Aotearoa New Zealand

To protect New Zealand's unique ecosystems and primary industries, imported plant materials must be constantly monitored at the border for high-threat pathogens. Techniques adopted for this purpose must be robust, accurate, rapid, and sufficiently agile to respond to new and emerging threats. Polymerase chain reaction (PCR), especially real-time PCR, remains an essential diagnostic tool but it is now being complemented by high-throughput sequencing using both Oxford Nanopore and Illumina technologies, allowing unbiased screening of whole populations. The demand for and value of Point-of-Use (PoU) technologies, which allow for in situ screening, are also increasing. Isothermal PoU molecular diagnostics based on recombinase polymerase amplification (RPA) and loop-mediated amplification (LAMP) do not require expensive equipment and can reach PCR-comparable levels of sensitivity. Recent advances in PoU technologies offer opportunities for increased specificity, accuracy, and sensitivities which makes them suitable for wider utilization by frontline or border staff. National and international activities and initiatives are adopted to improve both the plant virus biosecurity infrastructure and the integration, development, and harmonization of new virus diagnostic technologies.