Regulated non-quarantine pest Project

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

NAME OF THE ORGANISM: Rhizoctonia (anamorphic genus) (1RHIZG)


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

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?
  • No: Ornamental sector
Is it justified that the pest is listed at a taxonomic rank below species level?
Not relevant

  • Not candidate: Ornamental sector
Justification (if necessary):
When answering to the RNQP Questionnaire, for the Vegetable reproductive and planting material (excluding seeds) Sector, no EU Member State identified this entry as important and justified to keep Rhizoctonia listed at a higher level than the species level. No EU Member State proposed to replace this entry by pests listed at the Species level.
For the Ornamental sector, [except a selection (by accident) of this entry by FR as important for Begonia x hiemalis,] no EU Member State identified this entry as important and justified to keep Rhizoctonia listed at a higher level than the species level. Rhizoctonia solani on Lilium and Begonia x hiemalis, and Rhizoctonia tuliparum on Lilium are the main species identified by the experts on these two host plants. Numerous studies have been carried out on these ubiquitous and polyphagous fungus in order to characterize the diversity of its strains. Indeed, these differ in particular by their cultural characteristics, their virulence and in particular their host specificity. Experts recommended neither a listing at a higher level than the species level, nor to analyse the RNQP status of these two species. They considered that these pest/host combinations are more relevant for the vegetable sector.

HOST PLANT N°1: Begonia x hiemalis (BEGEH) for the Ornamental sector.

Origin of the listing:
Commission Directive 93/49/EEC

Plants for planting:
Plants intended for planting

Disqualified: No EU Member State considered this entry as important in the answers to the RNQP Questionnaire and gave justification(s) for a listing at a higher level than the species level. This entry will be covered by the 'Substantially free from' requirement that will remain in the Ornamental EU Marketing Directives.

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:

  • EPPO (1998) PP 2/13 (1). Good plant protection practice. Ornamental Plants under Protected Cultivation. Bulletin OEPP/EPPO Bulletin 28, 363–386;
  • Petersen L (1996) Some major pests in nurseries in Denmark in 1995. SP Rapport - Statens Planteavlsforsøg 4, 265-267;
  • Raabe RD, Hurlimann JH & Farnham DS (1978) Control of seedling diseases in tuberous begonias - progress report. Flower and Nursery Report No.Spring pp.1;