NAME OF THE ORGANISM: Ditylenchus dipsaci DITYDI

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: Ornamental 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: Ornamental sector

Justification (if necessary):

Remark for ornamentals:
- Allium: There is a large number of Allium species (and within the species, varieties) that are used as ornamentals.
Therefore it is suggested to include all Allium for ornamental use in the present evaluation.
- Ismene (host plant for D. dipsaci as mentioned in Directive 2000/29/EC) is nowadays named Hymenocallis for cultivated ornamental species and varieties.

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 (1993); Belgium (2007); Bulgaria (1993); Croatia (1996); Cyprus (1993); Czech Republic (1994); Denmark (1993); Estonia (1994); Finland (1993); France (2010); Germany (2014); Greece (1996); Hungary (2001); Ireland (1998); Italy (1992); Italy/Sicilia (2002); Latvia (2013); Lithuania (1998); Malta (1995); Netherlands (2015); Poland (2012); Portugal (1992); Portugal/Azores (1994); Romania (2011); Slovakia (2007); Slovenia (2003); Spain (2007); Sweden (1993); United Kingdom (1993); United Kingdom/England (1994); United Kingdom/Scotland (1994)

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/).

HOST PLANT N°1: Gladiolus (1GLAG) for the Ornamental sector.

Origin of the listing:

Commission Directive 93/49/EEC

Plants for planting:

Plants intended for planting

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:

Not candidate

Justification:

Gladiolus spp. are not given as a host of D. dipsaci in CABI 2015, ISPM 27 (IPPC 2016) or the EPPO Global Database, though a literature search found there are 3 records: of occurrence in greenhouses in Serbia (Grujičić, 2015), in Iraq (Stephan, 1989) and interceptions by India on flower bulbs from Europe (Arjun Lal & Rajan, 2005). In view of possible confusion with D destructor and that these are the only records, it is concluded Gladiolus is not host of this pest.

5 - Economic impact:

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

Justification:

The three references found concerning Gladiolus did not give any details of economic impact.

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: Gladiolus spp. are not considered to be a significant host and therefore Gladiolus plants are not considered to be a significant pathway.

8 - Tolerance level:

Is there a need to change the Tolerance level:

Proposed Tolerance levels:

Delisting.

9 - Risk management measures:

Is there a need to change the Risk management measure:

Proposed Risk management measure:

Delisting.

REFERENCES:

Arjun Lal & Rajan (2005) Nematodes intercepted in introduced germplasm of horticultural crops. Indian Journal of Plant Protection 33, 282-285;
CABI (Centre for Agricultural Bioscience International) (2015) Online. Datasheets Ditylenchus dipsaci (stem and bulb nematode). Invasive species compendium. CABI, Wallingford, UK. Available from http://www.cabi.org/isc/datasheet/19287;
IPPC (2016) Diagnostic protocols for regulated pests DP 8: Ditylenchus dipsaci and Ditylenchus destructor ISPM 27 ANNEX 8. Available at:
https://www.ippc.int/static/media/files/publication/en/2016/01/DP_08_2015_En__2015-12-22_Reformatted.pdf;
Grujičić G (2015) A contribution to the study of the stem nematode (Ditylenchus dipsaci Kühn) with a view of host plants in Serbia. Zaštita Bilja 66, 53-65;
Stephan ZA (1989) New hosts for Ditylenchus dipsaci in Iraq. International Nematology Network Newsletter 6, 30;