Pacific Pests, Pathogens and Weeds - Online edition

Pacific Pests, Pathogens, Weeds & Pesticides

Citrus sooty blotch (316)

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  • Widespread distribution. Citrus species. A 'cosmetic' disease. Fungal spots on fruit and leaves; on fruit, unsightly and affects quality. Unlikely to reduce yield unless severe on leaves and blocks sunlight.
  • Spots, black, circular, on upper and lower surfaces, up to 5 mm diameter. More spots on densely shaded trees.
  • Spores from the black spots spread by wind during wet or humid weather.
  • Cultural control: prune trees after main harvest removing unhealthy, unwanted and poorly positioned branches, and to improve air movement so that leaves and fruit dry faster; avoid shade of taller trees.
  • Chemical control: use horticultural oil. Try also white oil, or soap solution (see Fact Sheet no. 56).
Common Name

Citrus sooty blotch, black mould, black mildew

Scientific Name

Meliola citricola

AUTHORS Grahame Jackson & Eric McKenzie 
Information from (and Photos 1&2) McKenzie E (2013) Meliola citricola PaDIL -; and Donovan N, Hardy S (2007) Managing sooty blotch of citrus. Primefact 754. NSW, DPI, Australia. (; and from Citrus diseases and disorders of leaves and twigs (2016) UC/IPM. Agriculture and Natural Resources, University of California. (

Produced with support from the Australian Centre for International Agricultural Research under project PC/2010/090: Strengthening integrated crop management research in the Pacific Islands in support of sustainable intensification of high-value crop production, implemented by the University of Queensland and the Secretariat of the Pacific Community.

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