| Legend |
|---|
| Justification for qualification based on EPPO PM 4 Standards |
| Justification for disqualification |
| Additional or non-conclusive information |
| Standard text |
NAME OF THE ORGANISM: Xiphinema diversicaudatum (XIPHDI)
GENERAL INFORMATION ON THE PEST
Name as submitted in the project specification (if different):
Pest category:
Nematoda
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):
-
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):
Belgium (2001); Bulgaria (2001); Croatia (2001); Czech Republic (2001); Denmark (2001); France (2001); Germany (2014); Ireland (2001); Italy (2001); Netherlands (2001); Poland (2012); Portugal (2001); Portugal/Azores (2001); Portugal/Madeira (2001); Slovakia (2001); Spain (2006); Sweden (2001)
Conclusion:
Justification (if necessary):
Data of the presence of this pest on the EU territory are available in EPPO Global Database (https://gd.eppo.int/).
HOST PLANT N°1: Rubus (1RUBG) 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):
In EPPO Standard PM 4/10 Certification scheme for Rubus, soil should be tested and found free from virus-transmitting nematodes of the genera Longidorus and Xiphinema. Xiphinema diversicaudatum is listed as a vector of 'Arabis mosaic virus' and 'Strawberry latent ringspot virus'.
In the responses to the questionnaire, NL questioned the classification of organisms with vector properties as RNQP when not causing any direct impact. The methodology developed during the RNQP Project part I indicated that ‘Impact of vectors pathogens combinations may need to be considered as well as direct impact’. According to Regulation 2016/2031, Annex I, section 4 'Criteria to identify pests which qualify as a Union regulated non-quarantine pest' (as referred to in Articles 36 and 38), the ‘effects on the establishment, spread and impact of other pests, for example due to the capacity of the pest concerned to act as a vector for other pests’ should be considered for economic impact. According to ISPM 21, Section 3.3.1, ‘The ability to act as a vector for other pests may nevertheless be a relevant factor.’ Although, opportunity of listing such pests in the EU regulation is a decision by risk managers, EPPO had a general discussion in the Fruit SEWG on this issue.
NL also argued that the pest was soilborne and present in production areas. However, plants for planting may be moved with soil.
The Fruit SEWG decided to have a specific discussion on the relative importance of plants for planting as a pathway.
In the responses to the questionnaire, NL questioned the classification of organisms with vector properties as RNQP when not causing any direct impact. The methodology developed during the RNQP Project part I indicated that ‘Impact of vectors pathogens combinations may need to be considered as well as direct impact’. According to Regulation 2016/2031, Annex I, section 4 'Criteria to identify pests which qualify as a Union regulated non-quarantine pest' (as referred to in Articles 36 and 38), the ‘effects on the establishment, spread and impact of other pests, for example due to the capacity of the pest concerned to act as a vector for other pests’ should be considered for economic impact. According to ISPM 21, Section 3.3.1, ‘The ability to act as a vector for other pests may nevertheless be a relevant factor.’ Although, opportunity of listing such pests in the EU regulation is a decision by risk managers, EPPO had a general discussion in the Fruit SEWG on this issue.
NL also argued that the pest was soilborne and present in production areas. However, plants for planting may be moved with soil.
The Fruit SEWG decided to have a specific discussion on the relative importance of plants for planting as a pathway.
4 - Are the listed plants for planting the main* pathway for the "pest/host/intended use" combination? (*: significant compared to others):
No
Conclusion:
Not candidate
Justification:
Xiphinema diversicaudatum has an extensive host range. It is most frequently associated with plant species growing in temperate arable, permanent pasture and deciduous woodland soils and much less frequently with coniferous, scrubland and moorland plants (Thomas, 1970; Pitcher et al., 1974; Taylor and Brown, 1997 – cited from CABI, 2021). Rubus is reported as a host (CABI, 2021).
The nematode is actively moving < 1m per year. Consequently, the main pathway for dispersal is via soil, growth medium, soil attached to roots, etc. (CABI, 2021). Dissemination of the virus 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 Panel, 2013).
Long-distance dispersal of longidorids occurs when plants intended for planting (e.g. nursery stock) with soil adhering to the roots are harvested from infested fields and transported to new areas (EFSA PLH Panel, 2013). When moved with naked roots, plants for planting is not a pathway.
Xiphinema diversicaudatum is not known to be dispersed by true seeds (CABI, 2021).
This nematode is relatively widespread. However, it is not known whether it is already present in most fields:
In all Austrian winegrowing regions soil samples were taken from viticultural as well as agricultural areas and tested for nematodes of the family Longidoridae. To obtain a complete overview of the distribution of Longidoridae, samples were also taken from the riparian forests along the rivers Danube and March. The virus vector X. diversicaudatum was considered rare according to current knowledge, although X. diversicaudatum was fairly abundant in common pastures and under fruit trees in Styria, and in the alluvial forests of the Danube and the March (Tiefenbrunner et al., 2011).
In Spain, X. diversicaudatum is fairly widespread in the north (central region is the southern limit of its distribution), frequent in fruit trees (Arias & Andrés, 1989). It is reported from Andalucia, Aragon, Castilla y Leon, Castilla-La Mancha, Extremadura, Madrid, Navarra, La Rioja & Communidad Valanciana (SEF, 2023).
The Fruit SEWG considered that this free living nematode was very vulnerable. Even when plants for planting are cultivated in the field, new substrate is generally used for repotting. The substrate used is most often cleaned/steamed, bought from professional operators, and the risk that these nematodes are transported with plants for planting is considered limited.
Considering production practices and uncertainty on distribution, the Fruit SEWG concluded that plants for planting should not be considered a significant pathway.
The nematode is actively moving < 1m per year. Consequently, the main pathway for dispersal is via soil, growth medium, soil attached to roots, etc. (CABI, 2021). Dissemination of the virus 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 Panel, 2013).
Long-distance dispersal of longidorids occurs when plants intended for planting (e.g. nursery stock) with soil adhering to the roots are harvested from infested fields and transported to new areas (EFSA PLH Panel, 2013). When moved with naked roots, plants for planting is not a pathway.
Xiphinema diversicaudatum is not known to be dispersed by true seeds (CABI, 2021).
This nematode is relatively widespread. However, it is not known whether it is already present in most fields:
In all Austrian winegrowing regions soil samples were taken from viticultural as well as agricultural areas and tested for nematodes of the family Longidoridae. To obtain a complete overview of the distribution of Longidoridae, samples were also taken from the riparian forests along the rivers Danube and March. The virus vector X. diversicaudatum was considered rare according to current knowledge, although X. diversicaudatum was fairly abundant in common pastures and under fruit trees in Styria, and in the alluvial forests of the Danube and the March (Tiefenbrunner et al., 2011).
In Spain, X. diversicaudatum is fairly widespread in the north (central region is the southern limit of its distribution), frequent in fruit trees (Arias & Andrés, 1989). It is reported from Andalucia, Aragon, Castilla y Leon, Castilla-La Mancha, Extremadura, Madrid, Navarra, La Rioja & Communidad Valanciana (SEF, 2023).
The Fruit SEWG considered that this free living nematode was very vulnerable. Even when plants for planting are cultivated in the field, new substrate is generally used for repotting. The substrate used is most often cleaned/steamed, bought from professional operators, and the risk that these nematodes are transported with plants for planting is considered limited.
Considering production practices and uncertainty on distribution, the Fruit SEWG concluded that plants for planting should not be considered a significant pathway.
5 - Economic impact:
Are there documented reports of any economic impact on the host?
Justification:
In general, Longidorus spp. and Xiphinema spp. can cause direct feeding damage which can result in yield loss. However, there are many factors affecting the level of impact to the yield. The main factors include (but not limited to) infestation level, host, maturity of host, virus presence and external stresses. The potential damage from nepoviruses is typically of greater concern than direct nematode feeding.
Tomato black ring virus (TBRV), Arabis mosaic virus (AMV), Raspberry ringspot virus (RRV) and Strawberry latent ringspot virus (SLRV) are reported from this host (Fera internal records).
X. diversicaudatum is reported to vector AMV, RRV and SLRV (Taylor & Brown, 1997).
Tomato black ring virus (TBRV), Arabis mosaic virus (AMV), Raspberry ringspot virus (RRV) and Strawberry latent ringspot virus (SLRV) are reported from this host (Fera internal records).
X. diversicaudatum is reported to vector AMV, RRV and SLRV (Taylor & Brown, 1997).
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?
Conclusion:
Justification:
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?
Conclusion:
Justification:
7- Is the quality of the data sufficient to recommend the pest to be listed as a RNQP?
Conclusion:
Justification:
CONCLUSION ON THE STATUS:
Disqualified: plants for planting not considered as a significant pathway.
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:
- Arias M, Andrés MF (1989) Virus-vector nematodes in cereals and fruit crops in Spain. EPPO Bulletin 19, 625-632.
- CABI (2021) Xiphinema diversicaudatum (dagger nematode). CABI digital library (accessed 28/May/2024). https://www.cabidigitallibrary.org/doi/full/10.1079/cabicompendium.57028
- EFSA PLH Panel (EFSA Panel on Plant Health) (2013) 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 2013;11(10):3377, 83 pp.doi:10.2903/j.efsa.2013.3377.
- Pitcher RS, Siddiqi MR, Brown DJF (1974) Xiphinema diversicaudatum. C.I.H. Descriptions of Plant-parasitic Nematodes, Set 4, No. 60, 4 pp.
- SEF (2023) Xiphinema diversicaudatum, X. index, X. italiae y X. rivesi. En “Patógenos de plantas descritos en España”. Sociedad Española de Fitopatología.
- Šubíková V, Kollerová E & Slováková L (2002) Occurrence of nepoviruses in small fruits and fruit trees in Slovakia. Plant Protection Science 38, 367-369.
- Taylor CE & Brown DJF (1997) Nematode Vectors of Plant Viruses. Wallingford, UK: CAB International, (In press).
- Thomas PR (1970) Host status of some plants for Xiphinema diversicaudatum (Micol.) and their susceptibility to viruses transmitted by this species. Annals of Applied Biology 65, 169-178.
- Tiefenbrunner W, Gangl H, Leitner G, Riedle-Bauer M & Tiefenbrunner A (2011) Verbreitung und Häufigkeit wurzelparasitärer Nematoden der Familie Longidoridae in den Weinbauregionen Österreichs. Mitteilungen Klosterneuburg 61, 121-144.