NAME OF THE ORGANISM: Puccinia horiana PUCCHN
GENERAL INFORMATION ON THE PEST
Name as submitted in the project specification (if different):
Pest category:
Fungi
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):
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 (1993); Belgium (2011); Bulgaria (2011); Croatia (2011); Czech Republic (2011); Denmark (1993); France (2011); Germany (2011); Greece (1997); Greece/Kriti (1997); Hungary (2006); Italy (2010); Italy/Sicilia (1994); Latvia (2011); Netherlands (2015); Poland (2004); Portugal (2011); Romania (2011); Slovakia (2011); Slovenia (2011); Sweden (1998); United Kingdom (2011); United Kingdom/England (1994); United Kingdom/Northern Ireland (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: Chrysanthemum (Dendranthema) (1DDMG) 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):
Pest listed in EPPO PM 4/6(2) certification scheme for Chrysanthemum.
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:
Cultivars of Chrysanthemum × morifolium for cut flowers and pot chrysanthemum are mostly grown in protected cultivation, while multiflora plants (garden chrysanthemum) are mainly grown outdoors. Production under a protected cropping system is, under strict sanitation processes, sufficient to prevent infestation from the surrounding environment or previous crops. Plant material of Chrysanthemum × morifolium cultivars for propagation purposes originating from infested areas may carry P. horiana as teliospores in pustules or as mycelium, however existing certification schemes considerably reduce the risk of use of infected cuttings. Cut flowers may carry the pathogen, but current sanitary practices on nurseries should prevent their introduction.
The pathogen spreads naturally as teliospores and basidiospores and Chrysanthemum species are the only host species, and they occur in the wild or are widely grown throughout the area. The basidiospores are dispersed by wind, which can transport them on at least 700 metres and possibly several kilometres but this needs conditions of high RH, as they lose their germinability after five minutes at 80 % RH and after one hour at 90% (EFSA 2013). Hence the likelyhood of protected environments becoming infected in this way would appear to be low.
In conclusion, plants for planting are a pathway and are considered the main significant pathway compared to natural dispersal for crops grown in protected conditions, and also probably to crops grown outside, unless in close proximity to other infected crops or hosts under suitable environmental conditions.
The pathogen spreads naturally as teliospores and basidiospores and Chrysanthemum species are the only host species, and they occur in the wild or are widely grown throughout the area. The basidiospores are dispersed by wind, which can transport them on at least 700 metres and possibly several kilometres but this needs conditions of high RH, as they lose their germinability after five minutes at 80 % RH and after one hour at 90% (EFSA 2013). Hence the likelyhood of protected environments becoming infected in this way would appear to be low.
In conclusion, plants for planting are a pathway and are considered the main significant pathway compared to natural dispersal for crops grown in protected conditions, and also probably to crops grown outside, unless in close proximity to other infected crops or hosts under suitable environmental conditions.
5 - Economic impact:
Are there documented reports of any economic impact on the host?
Yes
Justification:
In most EU production areas the pathogen is considered established, and standard protective action is taken in the form of regular protective fungicide treatments and reductions in leaf wetness period where possible.
Higher impact is expected only in the case in which a crop of a susceptible cultivar is grown in conditions in which leaf wetness period is not or cannot be controlled and where no protective fungicides are applied. Such cases are currently very rare but, if they occur, the impact can be locally severe, especially if cuttings did not undergo a certification scheme and were infected.
Higher impact is expected only in the case in which a crop of a susceptible cultivar is grown in conditions in which leaf wetness period is not or cannot be controlled and where no protective fungicides are applied. Such cases are currently very rare but, if they occur, the impact can be locally severe, especially if cuttings did not undergo a certification scheme and were infected.
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:
Recommended for listing as an RNQP - based on EPPO PM 4 Standard.
8 - Tolerance level:
Is there a need to change the Tolerance level:
No
Proposed Tolerance levels:
Zero tolerance based on visual examination and/or treatment.
9 - Risk management measures:
Is there a need to change the Risk management measure:
Yes
Proposed Risk management measure:
(a) Plants intended for planting have been derived from mother plants which have been inspected at least monthly during the previous 3 months and no symptoms seen at the site of production;
or
(b) Mother plants showing symptoms have been removed and destroyed, along with plants within a 1m radius, and an appropriate physical or chemical treatment has been applied to the plants which have been inspected before dispatch and found free from symptoms.
or
(b) Mother plants showing symptoms have been removed and destroyed, along with plants within a 1m radius, and an appropriate physical or chemical treatment has been applied to the plants which have been inspected before dispatch and found free from symptoms.
Justification (if necessary):
Thermotherapy is available and supported by most cultivars (45°C during 5 minutes).
REFERENCES:
- EFSA Panel on Plant Health (PLH) (2013) Scientific Opinion on the risk to plant health posed by Puccinia horiana Hennings for the EU territory, with the indentification and evaluation of risk reduction options. EFSA Journal 2013;11(1):3069. [121 pp.]doi:10.2903/j.efsa.2013.3069. Available online: www.efsa.europa.eu/efsajournal;
- EPPO (2002) PM 4/6(2) Certification scheme for Chrysanthemum Bulletin OEPP/EPPO Bulletin 32, 105–114;