Mediterranean wood decay fungus

Fomitiporia mediterranea is a wood-decaying basidiomycete fungus belonging to the Hymenochaetaceae family. It is recognized in plant pathology as a major pathogen responsible for severe degradation of woody tissues in various perennial crops, acting as a primary agent in the complex syndrome known as esca.

The fungus primarily targets grapevines, causing symptoms such as wood necrosis, white rot, and the eventual sudden collapse of the plant. In addition to vineyards, it has a broad host range, infecting fruit trees like olive, fig, apple, and various landscape tree species, which significantly impacts the health and longevity of these agricultural plantings.

The biological cycle of the fungus begins with the dispersal of spores, which enter the host plant through wounds, particularly those caused by pruning or natural bark cracks. Once established, the mycelium penetrates deep into the xylem, secreting enzymes that break down lignin and cellulose, leading to the formation of internal cavities and white rot.

Environmental conditions such as mild temperatures (around 20-25°C) and moderate to high humidity favor the growth and reproduction of the fungus. Fruiting bodies typically develop on dead or dying parts of the host, acting as long-term inoculum sources that release spores during rainfall, spreading the infection to neighboring healthy plants.

Managing this pathogen is challenging because of its systemic nature within the woody tissue. Current control strategies focus on prevention and sanitation:

• Strict hygiene during pruning operations to avoid cross-contamination.
• Applying protective wound dressings to all significant cuts.
• Removing and destroying symptomatic wood to reduce spore pressure.
• Optimizing crop vigor to enhance the natural resistance of the trees and vines.