Phaeoacremonium sicilianum

Pathogen and Disease Type. Phaeoacremonium sicilianum is an ascomycete fungus identified as a causal agent of grapevine trunk diseases. This pathogen is part of a complex of fungi that colonize the xylem of woody plants, leading to systemic infection and the progressive deterioration of the vascular system within the vine’s perennial framework.

Susceptible Crops and Impact. The primary host of this pathogen is the cultivated grapevine (Vitis vinifera). The fungus infects the plant through wounds and colonizes the woody tissues. Over time, this colonization leads to severe structural degradation, reduced vigor, and the eventual death of the entire grapevine, impacting vineyard longevity and yields.

Symptoms and Signs. Infected vines often show characteristic foliar symptoms, such as interveinal chlorosis and necrosis. When examining the trunk or cordons through cross-sections, growers can observe distinctive dark brown or black staining of the wood. This internal necrosis disrupts water and nutrient transport, often leading to sudden wilting or gradual decline.

Conditions for Development. The fungus thrives in moist environments. Spores are primarily disseminated by wind and splashing rain, landing on pruning wounds or other mechanical injuries. The timing of pruning is critical; wounds left exposed in humid, cool conditions are highly susceptible to colonization by airborne spores of this pathogen.

Control and Preventive Measures. Management focuses on strict hygiene to prevent the spread of the pathogen within the vineyard:

• Sterilizing pruning tools between vines to prevent cross-contamination.
• Applying wound sealants or protective fungicides immediately after pruning.
• Prioritizing the removal and burning of severely symptomatic woody parts.
• Sourcing certified disease-free vine material for new vineyard establishment.