Regulated non-quarantine pest Project

An EU funded project for the benefit of the whole EPPO region

NAME OF THE ORGANISM: Stagonosporopsis chrysanthemi (Didymella ligulicola) (MYCOLG)


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

Pest category:

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?

Is the pest defined at the species level or lower?:

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
Is it justified that the pest is listed at a taxonomic rank below species level?
Not relevant

  • Candidate: Ornamental sector
2 – Status in the EU:
Is this pest already a quarantine pest for the whole EU?

Presence in the EU:

List of countries (EPPO Global Database):
Belgium (2007); France (1992); Germany (1993); Ireland (1993); Italy (1992); Lithuania (2010); Luxembourg (1992); Poland (1992); Romania (1992); Slovakia (1994); United Kingdom (1996); United Kingdom/England (1994); United Kingdom/Northern Ireland (1994); United Kingdom/Channel Islands (1994)


Justification (if necessary):
Data of the presence of this pest on the EU territory are available in EPPO Global Database (

HOST PLANT N°1: Chrysanthemum (Dendranthema) (1DDMG) for the Ornamental sector.

Origin of the listing:

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?
Evaluation continues

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

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 that prevent infection from the surrounding environment or previous crops. Spread from outside into a protected cropping system could potentially be by airborne ascospores within approximately 400m, whereas conidia are dispersed over short distances through rain splash or irrigation. However, for protected crops this is less likely to occur than for outside crops. Also spread could be by introduced infected cut flowers or pot plants, however these are under grower and legislative control, and no examples of outbreaks arising from these sources were given (EFSA PLH, 2013).
In conclusion, plants for planting are a pathway and are considered the main significant pathway compared to others for crops grown in protected conditions, and also probably to crops grown outside, unless in close proximity to other infected crops.

5 - Economic impact:

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

No recent reports on the effects of S. chrysanthemi on chrysanthemum crops have been found in the EU by the PLH Panel in the published literature, though in the past severe losses have occurred in other countries (EFSA PLH, 2013). Under the current host plant production system and the EU legislation, the overall impact of S. chrysanthemi in the EU is minor though in the absence of the EU legislation and of a [voluntary] certification scheme for the production of host plant propagation material, the potential impacts of S. chrysanthemi would increase (EFSA PLH, 2013).

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?

Not candidate

There is no added value for regulation above the 'substantially free from requirement': no problem in professional production systems and these systems are standard way of working).

Disqualified: Acceptable economic impact under current production systems and substantially free from requirement considered to be sufficient.

8 - Tolerance level:

Is there a need to change the Tolerance level:

Proposed Tolerance levels:

9 - Risk management measures:

Is there a need to change the Risk management measure:

Proposed Risk management measure:

  • EFSA Panel on Plant Health (PLH) (2013) Scientific Opinion on the risks to plant health posed by Stagonosporopsis chrysanthemi (Stevens) Crous, Vaghefi and Taylor [Didymella ligulicola (Baker, Dimock and Davis) Arx var. ligulicola; syn. Didymella ligulicola (Baker, Dimock and Davis) Arx] in the EU territory, with identification and evaluation of risk reduction options. EFSA Journal 11, 3376. Available online:;