EPPO RNQP

NAME OF THE ORGANISM: Xanthomonas arboricola pv. pruni (Xanthomonas campestris pv. pruni) (XANTPR)

GENERAL INFORMATION ON THE PEST

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

Pest category:

Bacteria

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, Ornamental sector, Forest reproductive material sector

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

Yes

Conclusion:

Candidate: Fruits (including hops) sector, Ornamental sector, Forest reproductive material sector

Justification (if necessary):

Among cultivated plants, major hosts in which disease severity is commonly high, are: Prunus salicina, P. persica, P. armeniaca, P. dulcis. Minor hosts, in which the disease may be less severe owing to a certain degree of tolerance, are: P. domestica, P. avium, P. cerasus, and P. laurocerasus. Other hosts are Japanese apricot (P. mume), Chinese wild peach (P. davidiana), P. buergeriana, P. crassipes and P. donarium. Rootstocks are, in general, resistant to the disease. P. spinosa (sloethorn or blackthorn), native to Europe and widely present throughout the EU, is not known to be a host or a reservoir plant (EFSA PLH, 2014).
For fruit and ornamental use: Experts proposed to continue the evaluation with a listing of the host at the genus level;
For forestry use: Prunus avium is the only Prunus species specifically listed in Annex I of EU Directive 1999/105, however evaluation continues taking into consideration other potential Prunus species.

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):

Belgium (2015); France (2014); Germany (2014); Italy (2014); Italy/Sicilia (1940); Italy/Sardegna (1992); Netherlands (2015); Romania (1992); Slovenia (2014); Spain (2016); Spain/Islas Baleares (2014)

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: Prunus (1PRNG) for the Fruits (including hops) sector.

Origin of the listing:

IIA2AWG

Plants for planting:

Plants intended for planting, other than seeds

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

Yes

Conclusion:

Qualified

Justification (if necessary):

Production of grafted trees, vegetatively propagated rootstocks and seedling rootstocks of cherry, almond, apricot, peach and plum are already covered by these EPPO PM 4 Standard.

CONCLUSION ON THE STATUS:

Recommended for listing as an RNQP, based on EPPO PM 4 Standard.

8 - Tolerance level:

Is there a need to change the Tolerance level:

Proposed Tolerance levels:

Zero tolerance based on visual examination.

9 - Risk management measures:

Is there a need to change the Risk management measure:

Yes

Proposed Risk management measure:

Non-certified material (‘CAC’):
(A) Derived from mother plants which have been inspected and found free from symptoms of Xanthomonas arboricola pv. pruni.
AND
(B) (a) Plants produced in areas known to be free from Xanthomonas arboricola pv. pruni;
or
(b) Site of production found free from Xanthomonas arboricola pv. pruni over the last complete growing season by visual inspection and any symptomatic plants in the immediate vicinity, and the neighbouring plants, rogued out and destroyed immediately, unless they are tested on the basis of a representative sample of symptomatic plants and it is shown in those tests that the symptoms are not caused by X arboricola;
or
(c) No more than 2% of plants in the lot showing symptoms during inspections at appropriate times during the last growing season, and those plants and any symptomatic plants in the site of production and the immediate vicinity, and the neighbouring plants, rogued out and destroyed immediately unless they are tested on the basis of a representative sample of symptomatic plants and it is shown in those tests that the symptoms are not caused by X arboricola;

Pre-basic, Basic and Certified: no additional measures to be considered.

Justification (if necessary):

Its is not possible to visually distinguish between shot hole symptoms caused by Xanthomonas arboricola pruni and common Pseudomonas. Measures also cover any infested Prunus avium produced for the forestry sector within the same site of production.

REFERENCES:

EFSA Panel on Plant Health (PLH) (2014) Scientific Opinion on pest categorisation of Xanthomonas campestris pv. pruni (Smith) Dye. EFSA Journal 2014; 12(10): 3857, 25 pp. doi:10.2903/j.efsa.2014.3857". http://www.efsa.europa.eu/en/efsajournal/doc/3857.pdf;
EU COM (2014) Recommendation of the Working Group on the Annexes of the Council Directive 2000/29/EC – Section II – Listing of Harmful Organisms as regards the future listing of Xanthomonas campestris pv. pruni (renamed Xanthomonas arboricola pv. pruni);

HOST PLANT N°2: Prunus (1PRNG) for the Ornamental sector.

Origin of the listing:

IIA2AWG

Plants for planting:

Plants intended for planting, other than seeds

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

Yes

Conclusion:

Qualified

Justification (if necessary):

Cherry, almond, apricot, peach and plum are already covered by a EPPO PM 4 Standard. These schemes are also suitable for the certification of ornamental Prunus.

CONCLUSION ON THE STATUS:

Recommended for listing as an RNQP, based on EPPO PM 4 Standard. Measures need to take account of the fact that symptoms are easier to see all year round on evergreen species (P. lusitanica and P. laurocerasus) and absence of visual symptoms on the traded material (current general ‘substantially free from’ requirement) could be sufficient for these.

8 - Tolerance level:

Is there a need to change the Tolerance level:

Proposed Tolerance levels:

Zero tolerance based on visual examination.

9 - Risk management measures:

Is there a need to change the Risk management measure:

Yes

Proposed Risk management measure:

(a) Plants produced in an area known to be free from Xanthomonas arboricola pv. pruni;
or
(b) Site of production found free from Xanthomonas arboricola pv. pruni over the last complete growing season by visual inspection and any symptomatic plants in the immediate vicinity, and the neighbouring plants, rogued out and destroyed immediately, unless they are tested on the basis of a representative sample of symptomatic plants and it is shown in those tests that the symptoms are not caused by X. arboricola;
or
(c) No more than 2% of plants in the lot showing symptoms during inspections at appropriate times during the last growing season, and those plants and any symptomatic plants in the site of production and the immediate vicinity, and the neighbouring plants, rogued out and destroyed immediately unless they are tested on the basis of a representative sample of symptomatic plants and it is shown in those tests that the symptoms are not caused by X arboricola;
or
(d) For evergreen species only, the plants have been inspected before dispatch and found free from symptoms of Xanthomonas arboricola pv. pruni.

Justification (if necessary):

Experts recommended extrapolating the risk management measures from the fruit sector, with an additional option for evergreen species. Its is not possible to visually distinguish between shot hole symptoms caused by Xanthomonas arboricola pruni and common Pseudomonas. Measures also cover any infested Prunus avium produced for the forestry sector within the same site of production.

REFERENCES:

EU COM (2014) Recommendation of the Working Group on the Annexes of the Council Directive 2000/29/EC – Section II – Listing of Harmful Organisms as regards the future listing of Xanthomonas campestris pv. pruni (renamed Xanthomonas arboricola pv. pruni);
EFSA Panel on Plant Health (PLH) (2014) Scientific Opinion on pest categorisation of Xanthomonas campestris pv. pruni (Smith) Dye. EFSA Journal 2014; 12(10): 3857, 25 pp. doi:10.2903/j.efsa.2014.3857". http://www.efsa.europa.eu/en/efsajournal/doc/3857.pdf;

HOST PLANT N°3: Prunus avium (PRNAV) for the Forest reproductive material sector.

Origin of the listing:

IIA2AWG

Plants for planting:

Plants intended for planting, other than seeds

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

Yes

Conclusion:

Evaluation continues

Justification (if necessary):

Prunus avium is covered by EPPO PM 4/29 Standard. However a forestry use is not mentioned. Even though the pest is listed in a PM 4 Standard, experts decided to continue the evaluation of this pest/host/intended use combination in regards to the economic impact.

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

Conclusion:

Justification:

5 - Economic impact:

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

Justification:

This organism will have most impact on stone fruit production, less for forestry and ornamental uses.

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:

Experts concluded that the disease is not important in forestry situations. The economic impact for forestry is estimated minimal and not unacceptable. As the Forestry and the Fruit production systems are usually separated, risk of transfer from forest to fruit production through rootstocks is estimated as low and is not considered. For the few cases where forestry plants are produced at the same site of production than fruit and ornamental plants (see comment from BE), these are addressed directly in the risk management measures.

CONCLUSION ON THE STATUS:

Disqualified: no economic impact in the forestry sector. However, if Prunus avium for the forestry sector are produced at the same site of production as for fruit or ornamental Prunus, these plants must be inspected to comply with the measures set out for these sectors.

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:

EU COM (2014) Recommendation of the Working Group on the Annexes of the Council Directive 2000/29/EC – Section II – Listing of Harmful Organisms as regards the future listing of Xanthomonas campestris pv. pruni (renamed Xanthomonas arboricola pv. pruni);
EFSA Panel on Plant Health (PLH) (2014) Scientific Opinion on pest categorisation of Xanthomonas campestris pv. pruni (Smith) Dye. EFSA Journal 2014; 12(10): 3857, 25 pp. doi:10.2903/j.efsa.2014.3857". http://www.efsa.europa.eu/en/efsajournal/doc/3857.pdf;