Regulated non-quarantine pest Project

An EU funded project for the benefit of the whole EPPO region




NAME OF THE ORGANISM: Garlic Common Latent Virus (GARCLV)


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 propagating and planting material (other than seeds) sector
Is it justified that the pest is listed at a taxonomic rank below species level?
 
Not relevant

Conclusion:
 
  • Candidate: Vegetable propagating and planting material (other than seeds) sector
2 – Status in the EU:
 
Is this pest already a quarantine pest for the whole EU?
 
No

Presence in the EU:
 
Yes

Conclusion:
 
candidate

Justification (if necessary):
 
The pest is probably distributed worldwide. It is present in Argentina, the former Czechoslovakia, France, Germany, Israel, Japan, the UK (Brunt, 1995) and Poland (CABI, 2014).

HOST PLANT N°1: Allium sativum (ALLSA) for the Vegetable propagating and planting material (other than seeds) sector.


Origin of the listing:
 
RNQP Questionnaire

Plants for planting:
 
Plants intended for planting


3 - Is the pest already listed in a PM4 standard on the concerned host plant?
 
No
 
Conclusion:
 
Evaluation continues

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

 
Justification:
 
The virus occurs in Allium sativum, A. ampeloprasum var. holmense and A. porrum with no obvious symptoms. Garlic common latent virus (GCLV) is transmitted by mechanical inoculation or vegetative propagation (Brunt 1995), found in 19 insect species (e.g T. tabaci) in Mexico (García-Rodríguez et al., 2014) and transmitted by aphids in a non-persistent manner (Vončina et al., 2016). It was found latently in many commercial varieties, local farmer's cultivars and breeding lines sampled and tested (many references, worldwide).
Vegetative propagation of garlic often leads to mixed virus infections that cause significant yield and quality reduction. OYDV, LYSV and GCLV are the most common viruses in Allium species in the Mediterranean region (Vončina et al., 2016).
As garlic cloves and sometimes transplants grown from seed are used for planting, these are a pathway and could be a significant pathway for GCLV if they were not produced under secure insect-proof conditions and are then grown in fields where appropriate cultivations (removal of alternate hosts garlic and leek) and controls against aphids, have been carried out.

5 - Economic impact:

Are there documented reports of any economic impact on the host?
 
No

Justification:
 
Onion yellow dwarf virus (OYDV), Leek yellow stripe virus (LYSV) and Garlic common latent virus (GCLV) are the most common viruses in Allium species in the Mediterranean region (Vončina et al., 2016) although no direct references of any impact of GCLV on garlic alone could be found. GCLV is not responsible for symptoms and does not appear to affect yields (Lot & Delécolle, 1996). No economic impact is known because of the absence of associated symptom (= latent virus) although its presence is important in many European countries (including Italy & France). Losses could be possible in association with other potyvirus (Eric VERDIN, INRA Montfavet 2017, pers. com.).

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?
 
No

Conclusion:
 
Not candidate

Justification:
 


CONCLUSION ON THE STATUS:
 
Disqualified: No economic impact is known because of the absence of associated symptom (latent virus).


8 - Tolerance level:

Is there a need to change the Tolerance level:
 
No

Proposed Tolerance levels:
 
Not recommended for the RNQP status.

9 - Risk management measures:

Is there a need to change the Risk management measure:
 
No

Proposed Risk management measure:
 
Not recommended for the RNQP status.


REFERENCES:
  • Brunt A A, Crabtree K, Dallwitz M J, Gibbs A J, Watson L & Zurcher E J (1996 onwards) Plant Viruses Online: Descriptions and Lists from the VIDE Database. Garlic common latent (?) carlavirus. Version: 16th January 1997. Available at: http://sdb.im.ac.cn/vide/descr352.htm;
  • CABI (Centre for Agricultural Bioscience International) (2014) Online. Datasheets Garlic common latent virus. Invasive species compendium. CABI, Wallingford, UK. Available from http://www.cabi.org/cpc/datasheet/119629;
  • García-Rodríguez OG, Pérez-Moreno L, Navarro-León MJ, Salas-Araiza MD, Martínez-Jaime OA, León-Galván MF & Núñez-Palenius HG (2014) Plant viruses in garlic-associated insects. Serie Horticultura 20, 147-156;
  • Lot H & Delécolle B (1996) Les virus de l'Ail : état de la recherche et moyens de lutte. INRA, Pathologie végétale, domaine Saint-Maurice, 84143 Montfavet cedex;
  • Vončina D, Ćurić K, Fabek S & Toth N (2016) First report of Onion yellow dwarf virus, Leek yellow stripe virus, and Garlic common latent virus on garlic in Croatia. Plant Disease 100, pp 656-657;