Chrysoporthe canker

Chrysoporthe cubensis is a destructive fungal pathogen responsible for causing canker disease in various Eucalyptus species. This disease represents a significant threat to timber production globally, particularly in tropical and subtropical regions. The fungus primarily attacks the tree's bark and cambium, eventually leading to the disruption of water and nutrient transport throughout the plant.

The disease targets various species within the Myrtaceae family, with Eucalyptus being the most commercially affected. Infection often occurs through natural openings in the bark, wounds caused by mechanical damage, or pruning sites. Young trees are particularly susceptible to the infection, which can lead to significant economic losses in forest management programs.

Symptoms are typically manifested as sunken necrotic lesions on the stem or at the base of branches. As the infection progresses, the bark may crack, and distinct orange-colored fungal structures (stromata) may emerge from the infected tissue. Eventually, the lesions can girdle the stem, causing the upper portion of the tree to wilt, turn yellow, and die, while the roots may sprout new shoots.

Environmental conditions play a crucial role in the development of the pathogen. High humidity and moderate to warm temperatures facilitate the production and dispersal of conidia (spores) via wind and rain splashes. Furthermore, intensive plantation management practices that lead to overcrowding or tree stress can exacerbate the spread of the fungus throughout the stand.

Effective management and prevention of Chrysoporthe canker rely on a multi-faceted approach:

• Selection and deployment of genetically resistant Eucalyptus clones.
• Maintaining optimal planting density to ensure proper airflow and reduce humidity.
• Rigorous sanitation, including the prompt removal and destruction of infected trees.
• Minimizing physical damage to tree bark during routine forestry operations to prevent infection entry points.