Dothiora canker

Dothiora canker is a destructive fungal disease caused by pathogens of the genus Dothiora. It primarily affects the bark and vascular tissues of various woody plants, including many important fruit-bearing species, leading to severe branch dieback and reduced tree vigor.

The disease frequently targets apple and pear trees, typically invading through bark wounds, frost cracks, or sunscald lesions. By colonizing the cambium and underlying xylem, the fungus disrupts the transport of nutrients and water, gradually weakening the host tree.

Visible symptoms include sunken, darkened areas on the bark that often develop cracks as the tissue dies. As the disease progresses, numerous small, black, eruptive fruiting bodies emerge from the affected bark, serving as the primary source for spore dissemination during wet weather.

Environmental conditions such as high humidity, frequent rainfall, and mild, damp winters significantly accelerate the development and spread of Dothiora. Spores are easily dispersed by wind and splashing water, allowing the fungus to infect healthy parts of the tree or adjacent plants.

Effective management requires a proactive approach including:

• Sanitary pruning of infected branches.
• Sterilization of pruning tools to prevent spread.
• Application of protective fungicides during the dormant season.
• Maintenance of tree health through proper fertilization and irrigation.