Dothiorella vidmadera

Taxonomy and Pathogen Classification: Dothiorella vidmadera is a species of ascomycetous fungi within the Botryosphaeriaceae family. It is recognized as a significant plant pathogen responsible for wood-decay diseases in viticulture. As a necrotrophic pathogen, it colonizes the vascular tissues and woody structures of host plants, leading to systemic decline.

Host Plants and Symptoms: The primary host for Dothiorella vidmadera is the grapevine (Vitis vinifera). Infection typically results in symptoms such as progressive dieback of spurs and cordons, stunted vegetative growth, and internal wood necrosis. In cross-sections of infected wood, dark streaks or localized necrotic areas become visible, representing the extent of colonization by the fungal mycelium.

Biology and Life Cycle: The fungus reproduces via pycnidia, which are small fruiting bodies produced on the surface of infected wood. Conidia (asexual spores) are released during rainfall events and are disseminated by water splash and wind. Once these spores land on pruning wounds or bark cracks, they germinate and penetrate the host tissue, eventually establishing a long-term infection within the woody framework of the vine.

Conditions for Development: The pathogen thrives in regions with warm climates and periodic moisture. Vineyard practices that create large pruning wounds, especially during wet weather, significantly increase the risk of infection. Furthermore, vines that are stressed due to water deficiency, poor soil conditions, or winter frost damage are more susceptible to the rapid colonization by this fungus.

Management and Control Strategies: Effective control requires a strict sanitary program to limit inoculum buildup in the vineyard. Growers should prioritize the timely removal and destruction of dead wood during winter pruning. Protecting pruning wounds with fungicide-treated pastes or biological control agents is critical. Additionally, cleaning pruning shears between vines helps prevent the mechanical transmission of the pathogen throughout the vineyard.