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UK Risk Register Details for Spiroplasma citri

This record was last updated on 17/01/2023

Common Names

  • Acorn disease
  • Citrus little leaf
  • Citrus stubborn disease
  • Little leaf of citrus
  • Stubborn disease of citrus

Scenario and Pathways

Scenario for Risk Register

  • show / hide
  • Pest is introduced

Pathway Assessed for Entry to UK

  • show / hide
  • Plants for planting (except seeds bulbs and tubers)

Common Pathways

  • show / hide
  • Plants for planting (except seeds bulbs and tubers)
  • Cut flowers or branches

Risk Ratings and Current Mitigations

Unmitigated Risks

Likelihood [1 - 5] 3
Spread [1 - 5] 3
Impact [1 - 5] 2
Value at Risk [1 - 5] 4
Likelihood x Impact [1 - 25] 6
UK Relative Risk Rating [1 - 125] 24

Current Mitigations

  • show / hide

Key mitigation for pest

Regulated non quarantine pest (Northern Ireland)



Industry Scheme

Contingency Plan



Mitigated Risks

Likelihood [1 - 5] 3
Spread [1 - 5] 3
Impact [1 - 5] 2
Value at Risk [1 - 5] 4
Likelihood x Impact [1 - 25] 6
UK Relative Risk Rating [1 - 125] 24

Proposed Actions

Proposed Actions



Management By Industry

Targeted Survey


Contingency Plan



Distribution and Pest Details


Country / Territory Status Notes
France Present (Limited)
Türkiye Present
Spain Present
United Kingdom Absent
Cyprus Present
Italy Present
North America Present
Mexico Present
United States Present
Oceania Present
New Zealand Present
Africa Present
Algeria Present
Egypt Present
Libya Present
Madagascar Present
Morocco Present
Somalia Present
Sudan Present
Tunisia Present
Malaysia Present
Oman Present
Pakistan Present
United Arab Emirates Present
Yemen Present
Saudi Arabia Present
Iran Present
Syria Present
Israel Present
Iraq Present
Jordan Present
Lebanon Present

Type of Pest

  • Bacterium

Host or Industry at Risk

  • show / hide

Daucus carota

Major Hosts

  • Allium cepa L.
  • Arabidopsis thaliana (L.) Heynh.
  • Armoracia lapathifolia Gilib. Ex Usteri
  • Brassica chinensis L.
  • Brassica napus var. napobrassica L.
  • Brassica nigra (L.) W.D.J. Koch
  • Brassica oleracea var. botrytis subvar. cultiflora L.
  • Brassica oleracea var. gemmifera L.
  • Brassica pekinensis (Lour.) Rupr.
  • Brassica rapa L. em. Metzg.
  • Brassica tournefortii Gouan
  • Callistephus chinensis (L.) Nees
  • Carthamus tinctorius L.
  • Catharanthus roseus (L.) G.Don
  • Citrofortunella microcarpa (Bunge) Wijnands
  • Citroncirus webberi Ingram & H.E.Moore
  • Citrus aurantium subsp. aurantium Linnaeus
  • Citrus jambhiri Lushington
  • Citrus limettioides Tanaka
  • Citrus limon (Linnaeus) N.L.Burman
  • Citrus maxima (Burman) Merrill
  • Citrus paradisi Macfadyen
  • Citrus reticulata (s.l.)
  • Citrus sinensis (Linnaeus) Osbeck
  • Citrus x limonia Osbeck
  • Citrus x tangelo Ingram & Moore
  • Cucurbita pepo var. melopepo L.
  • Daucus carota L.
  • Digitalis purpurea L.
  • Fortunella Swing.
  • Hirschfeldia incana (Jusl.) Lagr.-Foss.
  • Lactuca L.
  • Opuntia tuna (L.) Mill.
  • Plantago ovata Forssk.
  • Poncirus Rafin.
  • Poncirus trifoliata (Linnaeus) Rafinesque
  • Prunus avium ssp./var. avium L.
  • Prunus persica Batsch
  • Pyrus pyraster Burgsd.
  • Raphanus raphanistrum L.
  • Raphanus sativus Linnaeus
  • Sedum praealtum A.Dc. & Sesse Ex Dc.
  • Sisymbrium irio L.
  • Sisymbrium orientale Torn./L.
  • Tagetes erecta L.
  • Viola cornuta L.
  • Zinnia elegans Jacq.
  • Citrus
  • Brassica oleracea var. capitata L.

Threats to Protected Cultivation

Forest Tree Pests and Pathogens

Further Information

PRA Availability

PRA not available

Regulation and EPPO listing

  • show / hide

Regulated non quarantine pest (Northern Ireland)

Actions Indicated

  • show / hide


No statutory action in Great Britain. Statutory action on specified hosts in Northern Ireland.

General Comments

Spiroplasma affecting citrus and some field vegetables, vectored by leafhopper plant bugs. The pest is present in parts of Europe and elsewhere, but not known to be in the UK. The UK climate is likely to be too cool in summer for high levels of impacts to be seen.

Further Information


  • show / hide

Key uncertainty for pest

Impacts on non-Citrus hosts


Current distribution






UK distribution

Risk Records for this Pest