Pest survey card on regulated viruses and phytoplasmas that infect Rubus species

This pest survey card has been prepared in the context of EFSA’s mandate on plant pest surveillance (M-2020-0114) at the request of the European Commission. Its purpose is to guide EU Member States in gathering information for designing risk-based surveys on regulated viruses and phytoplasmas that infect species of the genus Rubus. These pathogens are Union quarantine pests that do not occur in the EU. All pathogens covered by this pest survey card are transmitted by vegetative propagation. Cherry rasp leaf virus (CRLV), raspberry latent virus, and ‘Candidatus Phytoplasma australiense’ can also be transmitted via vectors, whereas strawberry necrotic shock virus can be transmitted via pollen and seeds. Human-assisted spread through the movement of infected plants for planting is expected to be an important pathway for long distance spread of both viruses and ‘Ca. P. australiense’. The climatic conditions and availability of host plants in the EU are favourable for their establishment. CRLV and ‘Ca. P. australiense’
have a wider host range than Rubus, which includes other fruit species as well as other cultivated plants and wild host species. Detection surveys should focus on the main host (i.e. Rubus idaeus) but could also include other economically relevant fruit crops and cultivated hosts. All known host species should be considered in delimiting surveys. It is recommended to conduct detection
surveys of the regulated viruses and phytoplasmas by either asymptomatic (for viruses) or symptomatic (for ‘Ca. P. australiense’) sampling of Rubus plants. The identification of the regulated viruses in the collected leaf samples requires the application of specific laboratory tests or high-throughput sequencing. ‘Ca. P. australiense’ can be identified using a generic PCR followed by amplicon sequencing.