Botryodiplodia canker

Botryodiplodia canker is a significant fungal disease caused by pathogens of the Botryodiplodia genus. This disease is classified as a vascular and cortical necrosis, affecting the cambium and bark of various woody plants, leading to a disruption in sap flow and overall tree health decline.

The disease targets a wide range of fruit-bearing crops, including citrus, apples, pears, as well as grapevines and various ornamental trees. It primarily exploits weaknesses in the host plant caused by abiotic stressors such as drought, winter injury, or poor site conditions, making it a opportunistic pathogen.

The primary clinical signs include the appearance of depressed, dark brown or black lesions on branches and trunks. As the infection progresses, these areas crack, and the fungus produces characteristic black fruiting bodies, known as pycnidia, which emerge through the bark surface to release spores.

Development and spread are facilitated by warm, humid environments, typically thriving at temperatures between 20°C and 30°C. Spores are disseminated via water splash, wind currents, and contaminated pruning tools, entering the host through natural openings or mechanical wounds inflicted by harvesting or pruning.

The economic impact of the disease is severe, as it causes branch dieback, reduced fruit quality, and in extreme cases, the total loss of the tree. To maintain a healthy orchard, agricultural experts recommend the following measures:

• Strict sanitation by pruning and destroying infected wood promptly.
• Application of systemic and contact fungicides during high-risk periods.
• Use of appropriate wound dressings to prevent pathogen entry after pruning.
• Enhancing plant vigor through balanced nutrition and adequate irrigation to improve natural defense mechanisms.