Oyster mushroom

The genus Pleurotus, commonly known as oyster mushrooms, belongs to the kingdom Fungi and the phylum Basidiomycota. While commercially grown as food, in agricultural and forestry environments, they function as opportunistic pathogens that target stressed or damaged woody plants.

The fungus is primarily responsible for white rot, a form of decay that affects the structural integrity of the wood. It often colonizes fruit trees, poplars, and other broad-leaved species. Infection typically occurs when spores land on fresh wounds, frost cracks, or improper pruning cuts in the bark.

The biological cycle begins with the release of basidiospores from the mushroom cap. These spores are wind-dispersed and land on host tissue, where they germinate. The resulting hyphae penetrate the wood, secreting enzymes that break down lignin and cellulose, which are the main structural components of the tree.

Development is favored by humid conditions and moderate temperatures, allowing the mycelium to colonize the internal wood tissue progressively. As the fungus digests the wood, it leaves the tree structurally compromised, significantly increasing the risk of mechanical failure or windthrow during storms.

Economic damage includes the loss of fruit-bearing trees and potential safety hazards in orchards. Effective management requires:

• Maintaining tree vigor through proper fertilization and irrigation.
• Sanitizing pruning tools to prevent cross-contamination.
• Protecting wounds with appropriate sealants after pruning.
• Removing and destroying heavily infected wood to reduce spore load.