Dothiorella vinea-gemmas

Taxonomic position and nature of the pathogen: Dothiorella vinea-gemmas is a fungal plant pathogen belonging to the class Ascomycetes and the order Botryosphaeriales. It acts as a specialized pathogen that specifically targets the woody tissues of perennial plants, being identified as one of the causative agents of grapevine trunk diseases.

Diseases and host plants: The primary host of this pathogen is the cultivated grapevine (Vitis vinifera). The fungus is responsible for various manifestations of wood necrosis, including the dying off of buds (gemmas) and the formation of deep cankers on canes and trunks. Chronic infection leads to the systemic decay of vascular tissues.

Biology and life cycle: The life cycle of Dothiorella vinea-gemmas involves the production of pycnidia, which serve as fruiting bodies that release conidia (spores) in wet conditions. Infection occurs primarily through fresh pruning wounds, winter frost cracks, or damaged buds. Once inside, the mycelium spreads within the xylem, causing long-term damage that may remain asymptomatic for several seasons.

Conditions for development and severity: The pathogen thrives in regions with high humidity and moderate temperatures, which facilitate spore release and germination. The severity of the disease is exacerbated by environmental stress, such as drought or freeze damage. High incidence rates significantly reduce the productive lifespan of the vineyard, leading to reduced yields and eventual vine collapse.

Protection and control measures: Effective management requires an integrated approach to vineyard hygiene:

• Practicing strict sanitation by pruning diseased vines separately and removing all dead wood from the plot.
• Applying wound protectants immediately after winter pruning to create a physical barrier against spore infiltration.
• Disinfecting pruning shears between vines to prevent cross-contamination.
• Prioritizing the health of young planting material and screening for latent infections.
• Regular inspection of woody parts to detect early signs of localized necrosis.