Pacific Pests, Pathogens and Weeds - Online edition

Pacific Pests, Pathogens, Weeds & Pesticides

Citrus scab (048)

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  • Worldwide distribution. On lemon, rough lemon and mandarin. Other species of citrus - grapefruit, orange and pomelo - are also susceptible, but less so. An important disease.
  • The fungus distorts the leaves and makes the fruit unsightly. It stunts common rootstocks in the nursery, so they are difficult to bud.
  • Similar to citrus canker (see Fact Sheet no. 091), except leaves are stunted, wrinkled with torn margins.
  • Spread is by wind and rain, by insects, on nursery plants, and fruits.
  • Cultural control: make nurseries at distance from production areas; prune to keep open canopy, and improve air circulation.
  • Chemical: in the nursery, use copper or chlorothalonil at the beginning of leaf flushes.
Common Name

Common citrus scab

Scientific Name

Elsinoë fawcettii. The fungus has an asexual stage, Sphaceloma fawcettii; this is the stage that occurs throughout the Pacific. There are several strains of Sphaceloma fawcettii. Another species, Elsinoë australis is also known, which is more economically important but is less widespread.

AUTHORS Helen Tsatsia & Grahame Jackson
Information from Ferrin D (2010) Citrus Scab (Elsinoë  fawcettii) and Sweet orange scab (Elsinoë  australis). Louisiana Plant Pathology. Disease Identification and Management Series. LSU AgCenter. (; and Hardy S, Donovan N (2007) Managing lemon scab in citrus. Primefact 750. NSW, DPI, Australia. (; and CABI (2019) Elsinoë fawcettii (citrus scab) and CABI (2020) Elsinoë australis (citrus scab). Crop Protection Compendium. ( and; and from Citrus diseases, Citrus scab. USDA, University of Florida. (

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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