Crepidotus crocophyllus

Crepidotus crocophyllus is a wood-decaying fungus that acts as a pathogen in agricultural environments, primarily affecting woody perennial plants. While it is classified as a saprotroph in ecological terms, in orchard management, its colonization of tree limbs and trunks is treated as a significant pathological threat that leads to white rot development.

The causal agent is the basidiomycete fungus Crepidotus crocophyllus. It predominantly colonizes deciduous trees, including key pomaceous fruits such as apples and pears. The fungus typically targets trees that have been previously weakened by environmental stress, mechanical damage, or lack of proper pruning.

Symptoms of the infection include the emergence of characteristic sessile, fan-shaped fruiting bodies with distinct saffron-colored gills. Internally, the fungus degrades the woody tissue, causing white rot. This decay process reduces the mechanical integrity of the wood, resulting in brittle branches that are highly susceptible to breakage under wind or fruit load.

Conditions favorable for the spread of this pathogen include high ambient humidity and temperatures between 15°C and 25°C. Spores are disseminated by wind, rain, and insects, entering the host plant through wounds in the bark or unhealed pruning sites. Dense, unpruned orchard layouts significantly increase the humidity levels around the trees, facilitating spore germination.

The economic damage associated with this fungus involves the loss of productive wood and the potential death of infected trees. Effective protection measures include:

• Strict sanitation practices, including the removal and destruction of infected wood.
• Application of specialized wound dressings or fungicides on large pruning cuts.
• Protection of the bark against environmental stresses and sunscald.
• Maintaining tree vigor through balanced fertilization and appropriate water management.