Detection and Epidemiology of Pospiviroids 2 (DEP2)

Pospiviroids are plant pathogens, composed only of infectious circular RNA molecules, which are both latent on many ornamentals and harmful for cultivated plant species like tomato, potato, sweet pepper, citrus or chrysanthemum. Throughout the world, these pathogens cause sporadic outbreaks on susceptible annual crops while they often remain undetected although widespread on ornamentals. To assess the risk posed by pospiviroids in the EU, the link between this potential ornamental reservoir and the outbreaks on solanaceous as well as the role of infected seeds in these contaminations have been recently reviewed by the EFSA panel on plant health (PLH) (EFSA, 2011). However, the continuing uncertainty over the role of insects and infected seeds in the spreading of pospiviroids complicated the likelihood assessment of these transmission routes. On the other hand, the PLH concluded that disinfection measures and the accurate generic detection of pospiviroids are among the indispensable tools for the management of these diseases. The project DEP2 (Detection and Epidemiology of Pospiviroids 2) thus has focused on these different elements to decrease the uncertainty about the routes of interspecific transmission (WP2) and seed transmission (WP3), compare available generic detection methods (WP4) and evaluate the efficacy of the only approved pospiviroid disinfectant in EU (WP5)