Phaeomoniellales

Phaeomoniellales refers to an order of fungi, with Phaeomoniella chlamydospora being the most significant species involved in grapevine trunk diseases. This pathogen is highly destructive and is recognized as a major contributor to syndromes such as Petri disease and Esca, which threaten the longevity of vineyards worldwide.

The disease primarily targets the xylem tissues of grapevine cultivars, causing internal necrosis. By obstructing the vascular system, the fungus impairs the plant's ability to transport water and essential nutrients, which leads to slow decline or sudden collapse of the vine depending on the intensity of the infection.

Symptoms are often internal and can be difficult to diagnose in early stages. External indicators include stunted shoot growth, interveinal chlorosis on leaves, and reduced yields. When the trunk is cross-sectioned, growers may observe distinct dark streaking or spotting within the woody tissue, confirming the presence of the pathogen.

Environmental factors such as high humidity and rainfall promote the dispersal of spores from infected wood to fresh pruning wounds. The pathogen is often introduced into a vineyard through infected propagation material, emphasizing the importance of sourcing vines from certified nurseries that practice strict pathogen testing.

Effective management requires a combination of strict horticultural practices and prophylactic measures to limit the spread. The following strategies are essential for long-term vineyard health:

• Strict sterilization of pruning tools with approved disinfectants between vines.
• Protection of fresh pruning wounds using specialized wound sealants or biological control agents.
• Removal and destruction of infected vine wood to reduce inoculum sources.
• Rigorous selection of planting stock to ensure absence of internal fungal colonization.
• Maintaining vine vigor through proper irrigation and nutrition to increase resistance to fungal colonization.