- 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).
Pacific Pests, Pathogens, Weeds & Pesticides - Online edition
Pacific Pests, Pathogens, Weeds & Pesticides
Citrus sooty blotch (316)
Citrus sooty blotch, black mould, black mildew
Meliola citricola
AUTHORS Grahame Jackson & Eric McKenzie
Information from (and Photos 1&2) McKenzie E (2013) Meliola citricola PaDIL - http://www.padil.gov.au; and Donovan N, Hardy S (2007) Managing sooty blotch of citrus. Primefact 754. NSW, DPI, Australia. (http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0007/138346/Managing-sooty-blotch-of-citrus.pdf); and from Citrus diseases and disorders of leaves and twigs (2016) UC/IPM. Agriculture and Natural Resources, University of California. (http://ipm.ucanr.edu/PMG/C107/m107bpleaftwigdis.html).
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.