Botryobasidium subcoronatum

Botryobasidium subcoronatum is a basidiomycete fungus that primarily functions as a wood-decay agent in forest ecosystems. However, in agricultural and horticultural settings, it may act as an opportunistic pathogen. While not a primary parasite, it can colonize stressed plants, particularly those growing in high-humidity environments, causing tissue degradation and necrosis.

The disease mechanism involves the formation of a loose, web-like mycelium that spreads over the plant's surface. The fungus secretes enzymatic compounds that degrade cell walls, facilitating the transition from saprotrophic feeding to opportunistic parasitism. This process weakens the host's integrity and can lead to systemic decay if left unchecked.

Plants affected by this pathogen include various shrubs, seedlings, and ornamental species. It is particularly dangerous in nurseries or greenhouses where high planting density and high moisture create ideal conditions for fungal proliferation. Roots, crowns, and lower stems are the most common points of initial infection.

Symptomatology includes a faint white to cream-colored mycelial mat on the stems or soil surface surrounding the plant. Infected tissues typically lose their structural firmness, appearing discolored and soft. In severe cases, the plant may suffer from wilting and eventual collapse as the vascular system becomes compromised by the advancing fungal colonization.

Effective management strategies center on creating an unfavorable environment for the fungus. Key measures include:

• Optimizing spacing to enhance airflow and decrease humidity;
• Implementing proper drainage to prevent water stagnation;
• Maintaining rigorous sanitation by removing decaying organic matter;
• Applying appropriate fungicides to control surface mycelium spread.