EPPO RNQP

NAME OF THE ORGANISM: Citrus exocortis viroid (CEVD00)

GENERAL INFORMATION ON THE PEST

Name as submitted in the project specification (if different to the preferred name):

Pest category:

Viruses and viroids

1- Identity of the pest/Level of taxonomic listing:

Is the organism clearly a single taxonomic entity and can it be adequately distinguished from other entities of the same rank?

Yes

Is the pest defined at the species level or lower?:

Yes

Can listing of the pest at a taxonomic level higher than species be supported by scientific reasons or can species be identified within the taxonomic rank which are the (main) pests of concern?

Not relevant: Vegetable seed sector

Is it justified that the pest is listed at a taxonomic rank below species level?

Not relevant

Conclusion:

Candidate: Vegetable seed sector

Justification (if necessary):

Overall, methods for reliable detection and identification/discrimination of pospiviroids are available, although their high sensitivity implies the risk of false-positive reactions because of cross-contamination. These techniques are already widely used by EU MS as indicated by the answers received to the questionnaire sent by EFSA (EFSA PLH, 2011).

2 – Status in the EU:

Is this pest already a quarantine pest for the whole EU?

Presence in the EU:

Yes

List of countries (EPPO Global Database):

Austria (2010); Belgium (2014); Cyprus (2011); Czech Republic (2010); France (1979); France/Corse (1994); Germany (2008); Greece (2013); Italy (2011); Italy/Sicilia (1994); Italy/Sardegna (1994); Netherlands (2008); Portugal (2006); Slovenia (2011); Spain (1979)

Conclusion:

candidate

Justification (if necessary):

Data of the presence of this pest on the EU territory are available in EPPO Global Database (https://gd.eppo.int/). The report of a Pest Risk Analysis for Citrus exocortis viroid (EPPO, 2016), mainly based on EFSA PRA for solanaceous pospiviroids, lists the Countries where this pest is present: Austria, Belgium, Cyprus, Czech Republic, France, Germany, Greece, Italy, Montenegro, the Netherlands, Portugal, Russian Federation, Serbia, Slovenia, Spain and Turkey.

HOST PLANT N°1: Solanum melongena (SOLME) for the Vegetable seed sector.

Origin of the listing:

EFSA PRA (EFSA PLH, 2011)

Plants for planting:

Seeds

3 - Is the pest already listed in a PM4 standard on the concerned host plant?

Conclusion:

Evaluation continues

4 - Are the listed plants for planting the main* pathway for the "pest/host/intended use" combination? (*: significant compared to others):

Conclusion:

Justification:

Solanum melongena (EFSA, 2011) is described as a host plant. The two most important means of spread are mechanical transmission and plant for planting (except seeds). Two other means of spread are, seed- and pollen- transmission, and insect transmission, and need to be considered although they are less important (EPPO, 2016). The SEWG commented that there are no reports of any pospiviroïd transmission by aubergine seed.

5 - Economic impact:

Are there documented reports of any economic impact on the host?

No impact

Justification:

CEVd is symptomless in aubergines (EFSA, 2011)

What is the likely economic impact of the pest irrespective of its infestation source in the absence of phytosanitary measures? (= official measures)

Minimal

Is the economic impact due to the presence of the pest on the named host plant for planting, acceptable to the propagation and end user sectors concerned?

Yes

Is there unacceptable economic impact caused to other hosts (or the same host with a different intended use) produced at the same place of production due to the transfer of the pest from the named host plant for planting?

Conclusion:

Not candidate

Justification:

No damage is recorded on aubergine (Solanum melongena). Only symptomless CEVd infections have been reported in aubergine (EFSA PLH, 2011).
However aubergine crops would pose a risk to tomato since they may be grown in close proximity (see unacceptable economic impact on tomato).
The SEWG concluded that there are not enough data to recommend the pest to be listed as a RNQP in aubergine seeds. According the data in EFSA-PLH, there is no experimental evidence regarding any pospiviroids spread through aubergine seeds that can support this decision. Experts recommended isolation from other potential sources of infection, including host plants which may be latently infected of reproductive material, in the risk management measures for tomato.

CONCLUSION ON THE STATUS:

Disqualified: there are not sufficient evidence for seeds being a pathway and no impact on aubergine. However isolation from other potential sources of infection, including host plants which may be latently infected of reproductive material, will be proposed in the risk management measures for tomato.

8 - Tolerance level:

Is there a need to change the Tolerance level:

Proposed Tolerance levels:

Not recommended for the RNQP status.

9 - Risk management measures:

Is there a need to change the Risk management measure:

Proposed Risk management measure:

Not recommended for the RNQP status.

REFERENCES:

EFSA Panel on Plant Health (PLH) (2011) Scientific Opinion on the assessment of the risk of solanaceous pospiviroids for the EU territory and the identification and evaluation of risk management options. EFSA Journal 2011;9(8):2330 [132 pp.]. doi:10.2903/j.efsa.2011. 2330; www.efsa.europa.eu/efsajournal;
EPPO (2016) Report of a Pest Risk Analysis for Citrus exocortis viroid;