Redbrenner

Redbrenner is the common name for the disease caused by the fungus Pseudopeziza tracheiphila. This pathogen belongs to the division Ascomycota and acts as a specific parasite on grapevines, infecting the vascular system and causing severe tissue damage known as red leaf spot or fire blight of grapes.

The disease primarily attacks the leaves of Vitis vinifera. The fungus invades the xylem vessels, causing a blockage that prevents the transport of water and nutrients to the leaf blades. This physiological disturbance results in necrotic lesions that spread between the veins, ultimately leading to leaf desiccation and premature defoliation.

The life cycle of Pseudopeziza tracheiphila involves survival as mycelium in infected fallen leaves during the dormant season. In the spring, when temperatures rise and rainfall occurs, these leaves produce apothecia. Ascospores are then discharged into the air and spread by wind or water splashes, facilitating the primary infection of young vine leaves.

Environmental conditions such as cool, wet springs and humid summers are highly conducive to the spread of this pathogen. Infections typically begin to manifest after flowering. In white grape varieties, affected areas turn yellow-brown, while in red varieties, the characteristic reddish-brown spots appear, eventually killing the leaf tissue if left untreated.

The impact of Redbrenner is significant due to the loss of photosynthetic area, which reduces vine vigor, decreases sugar accumulation in berries, and impairs the wood maturation required for winter survival. Control strategies include rigorous sanitation of the vineyard floor to remove infected debris, combined with the application of fungicides during the critical early growth stages.