- Widespread distribution. On citrus including grapefruit, kumquat, lemon, lime, mandarin, orange, pomelo and tangerine, as well as other genera in the citrus family. An important disease.
- Bacterial spots on both sides of leaves and fruit causing them to fall early. Fruit unsightly. Spots up to 10 mm, with haloes on the leaves. Cankers cause twig dieback.
- Worse on grapefruit, lemon, lime and sweet orange.
- Spreads in wind-driven rain, water splash, and nursery plants. Enters through natural openings, wounds (e.g., leafminers). Survival is in leaf litter, and weeds.
- Cultural control: ensure nursery is canker-free; keep out of orchard when leaves wet; plant windbreaks around and between rows; Valencia orange and mandarin tolerant.
- Chemical control: 2-3 copper fungicide sprays 3 weeks apart, beginning when fruits are about 5 mm diameter.
Pacific Pests, Pathogens and Weeds - Online edition
Pacific Pests, Pathogens, Weeds & Pesticides
Citrus canker (091)
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Summary
Common Name
Citrus bacterial canker
Scientific Name
Xanthomonas citri (also known as Xanthomonas citri pv. citri, and Xanthomonas citri subsp. citri).
AUTHORS Helen Tsatsia & Grahame Jackson
Information from CABI (2020) Xanthomonas citri (citrus canker). Crop Protection Compendium. (https://www.cabi.org/cpc/datasheet/56921); Citrus canker (2020) Department of Agriculture, Water and the Environment. (https://www.agriculture.gov.au/pests-diseases-weeds/plant/citrus-canker); Citrus canker (2019). Business Queensland. Queensland Government. (https://www.business.qld.gov.au/industries/farms-fishing-forestry/agriculture/crop-growing/priority-pest-disease/citrus-canker); and Plant Biosecurity and Product Integrity (2017) Citrus canker. Department of Primary Industries. NSW. Australia; and from Citrus canker (2019) Agriculture and Food. Department of Primary Industries and Regional Development. Government of Western Australia. (https://www.agric.wa.gov.au/citruscanker/citrus-canker). Photo 2 Kohler F, et al. (1997) Diseases of cultivated crops in Pacific Island countries. South Pacific Commission. Pirie Printers Pty Limited, Canberra, Australia. Photos 3-5 Richard Markham, ACIAR, Canberra.
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.
