Godronia canker

Godronia canker is a serious fungal disease caused by members of the Godronia genus (with Ascocoryne as the teleomorph stage). This pathogen is primarily known as the cause of stem blight and canker in various woody berry crops, significantly impacting yields and plant longevity if left untreated.

The disease primarily targets highbush blueberries, although other berry species can serve as hosts. The pathogen infiltrates the plant tissue, particularly targeting the stems and branches. It often enters the plant through natural openings, leaf scars, or physical injuries caused by mechanical pruning, frost damage, or insect activity, making healthy plant maintenance a key focus.

The diagnostic symptoms of Godronia canker include the appearance of reddish-brown, discolored spots on the stems. As the infection progresses, these spots expand into elongated, oval-shaped cankers with raised margins. Over time, the bark becomes brittle and may crack, while the fungal mycelium colonizes the underlying cambium and vascular tissues, ultimately leading to the girdling and death of the stem.

Environmental conditions play a critical role in the development of the disease. High humidity, mild temperatures, and poor air circulation within the shrub canopy create a favorable environment for the germination of fungal spores. Rain splashes and wind serve as the primary dispersal mechanisms, carrying the spores from infected stems to healthy tissues throughout the growing season.

Effective management strategies for Godronia canker prioritize both prevention and sanitation. Growers should implement strict pruning practices, ensuring all infected wood is removed and destroyed away from the field. Maintaining proper plant spacing is essential to facilitate air movement and reduce surface wetness on the stems. Chemical control involves the application of appropriate fungicides during the early spring and post-harvest periods to protect susceptible tissues from infection.