| Legend |
|---|
| Justification for qualification based on EPPO PM 4 Standards |
| Justification for disqualification |
| Additional or non-conclusive information |
| Standard text |
NAME OF THE ORGANISM: Nepovirus arabis (arabis mosaic virus) (ARMV00)
GENERAL INFORMATION ON THE PEST
Name as submitted in the project specification (if different):
Arabis mosaic virus
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: Fruits (including hops) sector
If necessary, please list the species:
-
Is it justified that the pest is listed at a taxonomic rank below species level?
Not relevant
Conclusion:
- Candidate: Fruits (including hops) sector
Justification (if necessary):
Arabis mosaic virus (ArMV) is a member of the family Secoviridae and belongs to the genus Nepovirus.
This virus can be detected and identified in host plants and nematode vectors by specific reverse transcription polymerase chain reaction assays (RT-PCR) and/or sequencing. Antisera are also available and widely used for virus surveys and monitoring as well as for indexing of planting materials to ensure freedom from viruses (EFSA PLH, 2013).
Remark for olive: RT-PCR is commonly used in olive, including in certification programs for the detection and characterization of such plant viruses (Faggioli et al., 2005; Çağlayan et al., 2008).
This virus can be detected and identified in host plants and nematode vectors by specific reverse transcription polymerase chain reaction assays (RT-PCR) and/or sequencing. Antisera are also available and widely used for virus surveys and monitoring as well as for indexing of planting materials to ensure freedom from viruses (EFSA PLH, 2013).
Remark for olive: RT-PCR is commonly used in olive, including in certification programs for the detection and characterization of such plant viruses (Faggioli et al., 2005; Çağlayan et al., 2008).
2 – Status in the EU:
Is this pest already a quarantine pest for the whole EU?
No
Presence in the EU:
Yes
List of countries (EPPO Global Database):
Austria (2014); Belgium (2017); Bulgaria (1995); Croatia (2012); Czech Republic (2007); Denmark (2019); Finland (2011); France (2000); Germany (2009); Greece (2020); Greece/Kriti (2020); Hungary (2009); Ireland (1997); Italy (2007); Latvia (1990); Lithuania (2006); Luxembourg (1996); Netherlands (2022); Poland (2018); Romania (2011); Slovenia (2017); Spain (2011); Sweden (1993)
Conclusion:
Candidate
Justification (if necessary):
ARMV is widely distributed in the EPPO region. Data of the presence of this pest on the EU territory are available in EPPO Global Database (https://gd.eppo.int/). In the EPPO region, the ArMV has been reported in olive trees from Italy, Lebanon, Portugal and Turkey (Albanese et al., 2012).
HOST PLANT N°1: Olea europaea (OLVEU) for the Fruits (including hops) sector.
Origin of the listing:
Commission Implementing Directive (EU) 2014/98/EU and Commission Implementing Regulation (EU) 2019/2072
Plants for planting:
Plants intended for planting
3 - Is the pest already listed in a PM4 standard on the concerned host plant?
Yes
Conclusion:
Evaluation continues
Justification (if necessary):
EPPO Standard PM 4/17 Certification scheme for olive trees and rootstock recommends testing for Arabis mosaic virus (ArMV). Full assessment of the RNQP status of ArMV was performed together with Strawberry latent ringspot virus (SLRSV) in 2021/2022 in the context of the revision of EPPO Standard PM 4/17. The RNQP status was considered justified by olive certification experts to prevent infection of other hosts produced at the same place of production.
Although PL considered in responses to the questionnaire that plants for planting was not the main pathway, this was not supported by enough justification.
When assessing the RNQP status of ArMV on Prunus avium and P. cerasus, the Fruit SEWG considered that the assessment performed in 2021/2022 should be revised: considering the wide host range of this virus, experts recommended that ArMV is not listed as an RNQP on these hosts only based on possible indirect economic impact (see section on impact).
Although PL considered in responses to the questionnaire that plants for planting was not the main pathway, this was not supported by enough justification.
When assessing the RNQP status of ArMV on Prunus avium and P. cerasus, the Fruit SEWG considered that the assessment performed in 2021/2022 should be revised: considering the wide host range of this virus, experts recommended that ArMV is not listed as an RNQP on these hosts only based on possible indirect economic impact (see section on impact).
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 main hosts of ArMV are strawberry, hop, Vitis spp., raspberry (Rubus idaeus), Rheum spp., Sambucus nigra, sugarbeet, celery, gladiolus, horseradish and lettuce. ArMV is naturally associated with wild plants.
Plants for planting is a significant pathway, either at local or long distance. In particular, this virus is known to be often transmitted through infected seeds (EFSA PLH, 2013), but seed transmission of ArMV in olive plants has not been demonstrated (Albanese et al., 2012; Lister & Murant, 1967). Seeds could also serve as reservoirs for the viruses in the soil (EFSA PLH, 2013).
The virus is transmitted by the longidorid nematode Xiphinema diversicaudatum (EFSA PLH, 2013), but there is no evidence of ArMV transmission to olive plants by this vector (Albanese et al., 2012). X. diversicaudatum is considered to be the most widely distributed longidorid in Europe and has been reported from most European countries except Finland, Romania and some of the southern Mediterranean countries (EFSA PLH, 2013). Nematode movement is limited and the distances they move are dependent on the physical and chemical properties of the soil matrix. Horizontal spread for X. diversicaudatum estimated in laboratory experiments was 64 cm per year in heavy clay soil but only 14 cm per year in sandy soil. Thomas (1981) concluded that the spread of X. diversicaudatum in the absence of plants is very limited but in the presence of suitable host plants both species disperse at a rate of about 10 cm per month. Dissemination of the virus over greater distances can occur if nematode vectors are dispersed with soil movements caused by rain or erosion. Nematodes may be carried in the soil adhering to farm equipment and machinery or, occasionally, to the feet of birds and other animals. Some nematodes can also be dispersed by wind-blown soil dust; however, this is unlikely for longidorids which generally do not withstand desiccation (EFSA PLH, 2013). Therefore, nematode movement would only play a role locally when olive plants are grown in close proximity with other host crops.
The virus is also mechanically transmitted, through wounding and by grafting or vegetative propagation of their hosts (EFSA PLH, 2013). However, this can be prevented when appropriate production practices are implemented.
Plants for planting is considered to be a significant pathway compared to other pathways.
Plants for planting is a significant pathway, either at local or long distance. In particular, this virus is known to be often transmitted through infected seeds (EFSA PLH, 2013), but seed transmission of ArMV in olive plants has not been demonstrated (Albanese et al., 2012; Lister & Murant, 1967). Seeds could also serve as reservoirs for the viruses in the soil (EFSA PLH, 2013).
The virus is transmitted by the longidorid nematode Xiphinema diversicaudatum (EFSA PLH, 2013), but there is no evidence of ArMV transmission to olive plants by this vector (Albanese et al., 2012). X. diversicaudatum is considered to be the most widely distributed longidorid in Europe and has been reported from most European countries except Finland, Romania and some of the southern Mediterranean countries (EFSA PLH, 2013). Nematode movement is limited and the distances they move are dependent on the physical and chemical properties of the soil matrix. Horizontal spread for X. diversicaudatum estimated in laboratory experiments was 64 cm per year in heavy clay soil but only 14 cm per year in sandy soil. Thomas (1981) concluded that the spread of X. diversicaudatum in the absence of plants is very limited but in the presence of suitable host plants both species disperse at a rate of about 10 cm per month. Dissemination of the virus over greater distances can occur if nematode vectors are dispersed with soil movements caused by rain or erosion. Nematodes may be carried in the soil adhering to farm equipment and machinery or, occasionally, to the feet of birds and other animals. Some nematodes can also be dispersed by wind-blown soil dust; however, this is unlikely for longidorids which generally do not withstand desiccation (EFSA PLH, 2013). Therefore, nematode movement would only play a role locally when olive plants are grown in close proximity with other host crops.
The virus is also mechanically transmitted, through wounding and by grafting or vegetative propagation of their hosts (EFSA PLH, 2013). However, this can be prevented when appropriate production practices are implemented.
Plants for planting is considered to be a significant pathway compared to other pathways.
5 - Economic impact:
Are there documented reports of any economic impact on the host?
No
Justification:
Olive trees infected with ArMV do not show any symptoms (Albanese et al., 2012).
What is the likely economic impact of the pest irrespective of its infestation source in the absence of phytosanitary measures? (= official measures)
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?
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:
No direct economic impact is reported for ArMV in olive.
Economic impact on other hosts:
ArMV and SLRSV, which are commonly found in mixed infections, can cause diseases in strawberry and in raspberry; and ArMV in grapevine. Symptoms vary depending on the host plant but also on the virus isolate, the plant cultivar, the season and the year.
ArMV infections of strawberry usually result in stunting and dwarfing leading to decline of the plant and rendering the crop unsustainable within one to two years. Depending on the cultivar, SLRSV infections either remain symptomless or resemble ArMV infections with severe stunting and vein yellowing of leaves. Similarly, crop losses of raspberry due to ArMV and SLRSV can be considerable when many plants are affected because infected plants will produce little or no fruit. However, the incidence of virus-infected plants generally remains localised because of limited spread by the nematode vectors (EFSA PLH, 2013).
In addition, ArMV is responsible for the bare bine of hop, the mosaic of arabis, the mosaic of rhubarb, the nettlehead of hop, split leaf blotch of hop, and the yellow net of forsythia (EFSA PLH, 2013)
Impact is limited by the existence of efficient voluntary certification systems for strawberry and raspberry and by modern cultivation practices.
When revising the EPPO PM 4 Standard Certification scheme for olive in 2021/2022, the expert working group considered that other crops (e.g. grapevine) could be impacted because of host plants for planting produced at the same place of production than olive (as is the case in some Italian or Slovenian nurseries) and infected there via the soil adhering to farm equipment and machinery. Controlling ArMV in olive plant production could help preventing infection of other hosts produced at the same place of production.
In 2024, this assessment was reviewed during the RNQP Project part 2 by the Fruit SEWG which considered that ArMV was very polyphagous. Although olive and grapevine may succeed in production fields (e.g. in Spain) or Prunus with strawberry fields (e.g. in south of France), it was considered that there was no particular reasons for regulating ArMV on P. avium, P. cerasus and Olea europeae, more than other species, for the possible indirect economic impact to other hosts.
Economic impact on other hosts:
ArMV and SLRSV, which are commonly found in mixed infections, can cause diseases in strawberry and in raspberry; and ArMV in grapevine. Symptoms vary depending on the host plant but also on the virus isolate, the plant cultivar, the season and the year.
ArMV infections of strawberry usually result in stunting and dwarfing leading to decline of the plant and rendering the crop unsustainable within one to two years. Depending on the cultivar, SLRSV infections either remain symptomless or resemble ArMV infections with severe stunting and vein yellowing of leaves. Similarly, crop losses of raspberry due to ArMV and SLRSV can be considerable when many plants are affected because infected plants will produce little or no fruit. However, the incidence of virus-infected plants generally remains localised because of limited spread by the nematode vectors (EFSA PLH, 2013).
In addition, ArMV is responsible for the bare bine of hop, the mosaic of arabis, the mosaic of rhubarb, the nettlehead of hop, split leaf blotch of hop, and the yellow net of forsythia (EFSA PLH, 2013)
Impact is limited by the existence of efficient voluntary certification systems for strawberry and raspberry and by modern cultivation practices.
When revising the EPPO PM 4 Standard Certification scheme for olive in 2021/2022, the expert working group considered that other crops (e.g. grapevine) could be impacted because of host plants for planting produced at the same place of production than olive (as is the case in some Italian or Slovenian nurseries) and infected there via the soil adhering to farm equipment and machinery. Controlling ArMV in olive plant production could help preventing infection of other hosts produced at the same place of production.
In 2024, this assessment was reviewed during the RNQP Project part 2 by the Fruit SEWG which considered that ArMV was very polyphagous. Although olive and grapevine may succeed in production fields (e.g. in Spain) or Prunus with strawberry fields (e.g. in south of France), it was considered that there was no particular reasons for regulating ArMV on P. avium, P. cerasus and Olea europeae, more than other species, for the possible indirect economic impact to other hosts.
6 - Are there feasible and effective measures available to prevent the presence of the pest on the plants for planting at an incidence above a certain threshold (including zero) to avoid an unacceptable economic impact as regards the relevant host plants?
Yes
Conclusion:
Candidate
Justification:
Inclusion in a certification scheme: Experts considered that testing only when producing the nuclear stock was sufficient (regular testing for the maintenance of the nuclear stock was not considered necessary in regard to the fairly limited risk of reinfection via natural spread).
7- Is the quality of the data sufficient to recommend the pest to be listed as a RNQP?
Yes
Conclusion:
Candidate
Justification:
CONCLUSION ON THE STATUS:
Disqualified: no direct economic impact
8 - Tolerance level:
Is there a need to change the Tolerance level:
Yes
Proposed Tolerance levels:
Delisting
9 - Risk management measures:
Is there a need to change the Risk management measure:
Yes
Proposed Risk management measure:
Delisting
REFERENCES:
- Albanese G, Saponari M & Faggioli F (2012) Olive Germplasm – The Olive Cultivation, Table Olive and Olive Oil Industry in Italy. Chapter 6. Phytosanitary certification. Available at http://dx.doi.org/10.5772/51722
- Çağlayan K, Serçe Ç U & Gazel M (2008) Olive viruses. Characterization, diagnosis & management of plant viruses. Volume 1: industrial crops 2008 pp.305–339.
- EFSA PLH (2013) EFSA Panel on Plant Health (PLH). Scientific opinion on the risk to plant health posed by Arabis mosaic virus, Raspberry ringspot virus, Strawberry latent ringspot virus and Tomato black ring virus to the EU territory with the identification and evaluation of risk reduction options. EFSA Journal 11(10):3377, 83 pp. doi:10.2903/j.efsa.2013.3377
- Faggioli F, Ferreti L, Albanese G, Sciarroni R, Pasquini G, Lumia V & Barba M (2005) Distribution of olive tree viruses in Italy as revealed by one-step rt-PCR. Journal of plant pathology 87, 45–59.
- Ferreti L, Faggioli G, Pasquini G, Sciarroni R, Pannelli G, Baldoni L & Barba M (2002) Strawberry latent ringspot virus (SLRSV) cause of differentiation among Raggiola and Frantoio olive cultivars. Journal of plant pathology 84, 171–200.
- Lister RM & Murant AF (1967) Seed-transmission of nematode-borne viruses. Annals of Applied Biology 59, 49–62.
- Roschetti A, Ferretti L, Muzzalupo I, Pellegrini F, Albanese G & Faggioli F.(2009) Evaluation of the possible effect of virus infections on olive propagation. Petria 19 (1), 18–28.