Pycnoporus sanguineus

Pycnoporus sanguineus is a wood-decaying basidiomycete fungus belonging to the Polyporaceae family. In agronomy and forest pathology, it is recognized as an agent that causes white rot in woody plants. This fungus acts as a decomposer, breaking down the complex structural components of wood such as cellulose and lignin, eventually leading to structural decay.

This fungus typically attacks a wide variety of hardwood trees. While it is primarily found on decaying stumps, logs, and dead branches, it can also infect living trees that have sustained physical injuries, broken branches, or poor-quality pruning cuts, acting as an opportunistic pathogen in weakened specimens.

The primary diagnostic sign of the presence of this fungus is the formation of vibrant orange to cinnabar-red fruiting bodies on the bark of the host tree. Inside the wood, the disease manifests as a significant loss of density, color change to a bleached or yellowish appearance, and loss of mechanical strength, which compromises the stability of the entire plant structure.

The development and spread of this fungus are heavily influenced by environmental factors such as high ambient humidity and warm temperatures. Spores are released into the air and travel via wind or vectors like insects, landing on exposed tissue where they germinate and colonize the wood. Periods of heavy rain followed by humidity spikes are especially conducive to the rapid spread of the mycelium.

Effective management and prevention strategies focus on maintaining tree vigor and protecting woody tissues from invasion:

• Regular monitoring and removal of dead or rotting wood from the orchard or forest area.
• Applying protective wound sealants or fungicidal pastes immediately after pruning to prevent spore entry.
• Sanitizing pruning tools with alcohol or appropriate disinfectants between tasks to prevent cross-contamination.
• Improving soil health and irrigation practices to ensure trees are strong enough to resist pathogen encroachment.