Phaeoacremonium minimum

Phaeoacremonium minimum is a significant fungal pathogen known as one of the primary causal agents of grapevine trunk diseases, including esca and Petri disease. This pathogen colonizes the vascular tissues of woody plants, leading to a progressive decline and long-term degradation of the plant's structural integrity.

The disease primarily affects grapevines (Vitis vinifera), causing substantial economic losses worldwide. While it is most notorious in viticulture, the pathogen is also capable of infecting various other woody species, including stone fruits, thereby representing a broad risk in agricultural environments.

Symptoms in vineyards are highly variable, ranging from chronic foliar symptoms, such as interveinal chlorosis and necrosis described as "tiger striping," to sudden plant collapse known as apoplexy. Internally, the wood displays dark, necrotic spots and streaks, which indicate the systemic spread of the fungus throughout the xylem.

The infection process is primarily driven by spore dispersal through rain and wind, which infect the plant through pruning wounds or other mechanical injuries. Warm and humid conditions favor the release and germination of spores, making the timing of vineyard operations, particularly winter and summer pruning, critical for disease management.

Management is largely based on preventive cultural practices, as there are currently no effective curative treatments for infected wood. Key strategies include disinfecting pruning tools, applying protective sealants to large cuts, and performing sanitary pruning to remove symptomatic wood. Ensuring the use of healthy, nursery-certified planting material is essential to prevent the introduction of the pathogen into new vineyard blocks.