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Summary of the findings of an EFSA Scientific Opinion on solanaceous pospiviroids, and proposal for a future policy approach for Citrus exocortis viroid, Columnea latent viroid, Pepper chat fruit viroid and Tomato planta macho viroid.

Description

[Draft for stakeholder comments up to 2023-06-28]


Viroids are the smallest known pathogen of plants, consisting of a single-strand RNA molecule. Viroids differ from viruses in that they lack a protein shell. Citrus exocortis viroid (CEVd), Columnea latent viroid (CLVd), Pepper chat fruit viroid (PCFVd) and Tomato planta macho viroid (TPMVd) are viroids belonging to the genus Pospiviroid. The direct effects of these pospiviroids mainly concern tomato (Solanum lycopersicum) and pepper (Capsicum annuum) as they cause yield and quality losses. These viroids are not known to occur in Great Britain (all outbreaks have been eradicated) and are currently listed in the legislation as provisional GB quarantine pests (the retained Implementing Regulation 2019/2072, Annex 2A).  A summary of the main findings of an EFSA assessment on the risk posed by solanaceous pospiviroids to the EU is given below, in addition to some comments on the significance of the conclusions to GB. It is proposed that the aforementioned viroids are listed as GB quarantine pests. Measures for tomato and pepper seeds, and plants intended for planting are also proposed.  The viroids under consideration here will henceforth be referred to by their initialism, whereas those not being considered will be referred to by their species name.  In the EFSA Scientific Opinion on solanaceous pospiviroids (as a whole), the three main pathways for introduction were considered to be: true (botanical) seeds of hosts, host plants for planting, and seed potato (Solanum tuberosum) tubers (potato is not a known natural host of the four viroids being considered here; this was considered a main pathway for Potato spindle tuber viroid).  

N.B. Tomato apical stunt viroid, Tomato chlorotic dwarf viroid, Chrysanthemum stunt viroid and Potato spindle tuber viroid which are also assessed in the EFSA Opinion are already regulated as RNQPs in GB (regulated non-quarantine pests that have a limited presence). The EFSA Opinion also refers to Mexican papita viroid which is now thought to be the same species as TPMVd.

Organisms

  • Citrus exocortis viroid
  • Columnea latent viroid
  • Pepper chat fruit viroid
  • Tomato planta macho viroid

Hosts

  • Capsicum
  • Solanum lycopersicum

Files

Type File Size
Pest Risk Analysis Download 243,21kB

PRA Area

  • United Kingdom