Godronia canker

Godronia canker is a fungal disease primarily affecting various species of Vaccinium, most notably highbush blueberry. The pathogen responsible for this infection is the fungus Godronia cassandrae. This disease manifests as cankers on stems, which eventually lead to the girdling and death of the affected plant tissues.

The disease targets woody stems, showing a high preference for young, succulent growth or areas with previous mechanical injuries. By invading the cortical tissues, the fungus disrupts the translocation of nutrients, causing severe wilting of the leaves above the infection site and ultimately leading to the drying out of the entire branch.

Early symptoms include small reddish-brown or purple spots on the stem, which expand and deepen over time. As the canker progresses, the bark in the affected area may crack or peel, revealing necrotic wood underneath. During moist conditions, small, disc-shaped fruiting bodies emerge on the surface of the canker to release spores.

Environmental conditions characterized by high humidity and cool to moderate temperatures are highly favorable for the development and dissemination of the pathogen. Spores can remain viable in debris and dormant branches throughout the winter, providing a constant source of inoculum that can infect new growth during the spring rainy season.

Integrated pest management remains the most effective approach to control Godronia canker:

• Aggressive pruning of all symptomatic stems to reduce the inoculum level in the plantation.
• Maintaining optimal row spacing to ensure adequate sunlight penetration and airflow.
• Application of protective fungicides during the dormant season and early spring.
• Rigorous sanitation practices to prevent the transmission of spores via contaminated pruning tools.