Biosecurity alert: Citrus canker

Page last updated: Wednesday, 20 February 2019 - 9:14pm

The Department of Primary Industries and Regional Development has taken action to protect Western Australia’s citrus growers from the threat of citrus canker following confirmation that the disease has been detected on three properties in the State's north, linked to plants imported from the Northern Territory.

The disease has been detected at two retail businesses at Kununurra and at a property in Wyndham.


Quarantine Areas Notice is currently in place. It includes Restricted Areas and Control Areas, which detail restrictions on the movement of citrus canker host plants and fruit.

Citrus canker is a highly-damaging, contagious disease of citrus caused by the bacteria Xanthomonas citri subsp. citri. It affects some Rutaceous plant species, including all citrus species (such as grapefruit, lime, lemon, mandarin, orange, tangerine, cumquat and pomelo). A list of host plants is available in the Quarantine Areas Notice.

While citrus canker does not pose a risk to human health and fruit remains safe to eat, it has serious impacts on citrus production. Infected trees display unsightly lesions, which can form on leaves, fruit and stems.

Citrus canker can be spread rapidly over short distances, particularly in tropical and subtropical climates by wind-blown rain. Overhead irrigation systems can also spread the disease. Long distance spread occurs by people moving infected plant material or equipment, or through flooding or cyclones.