Grapevine red vein virus

The causative agent of this disease is the Ampelovirus venarubi, a member of the Ampelovirus genus within the Closteroviridae family. It is a viral pathogen that primarily affects the plant's vascular tissue, disrupting nutrient transport and causing long-term systemic infection in the grapevine.

The primary host for this virus is the grapevine (Vitis vinifera). The virus is highly specific to this crop, and different varieties may show varying levels of sensitivity, which complicates early diagnosis and disease management in commercial vineyards.

The key symptom of the infection is the red discoloration of the veins in the leaves, which typically becomes visible in the late summer months. Infected vines often exhibit leaf curling, stunted shoot growth, and a reduction in photosynthetic efficiency, which severely impacts the maturation of the clusters and sugar accumulation.

The virus is disseminated primarily through the movement of infected propagation material, such as cuttings and rootstocks. Furthermore, it is transmitted by insect vectors, including mealybugs and scale insects, which facilitate the spread of the virus within and between neighboring vineyard blocks.

The economic impact of Ampelovirus venarubi is significant, resulting in yield losses and diminished grape quality. Infected vines are weakened, showing reduced tolerance to environmental stressors like frost and drought, which eventually leads to a decline in productivity and necessitates the removal of affected blocks.

Management of the virus relies entirely on prophylactic measures as there is no chemical cure for viral plant infections. Essential strategies include:

• ensuring the use of certified, virus-free planting material;
• implementing strict quarantine and sanitation procedures in the nursery and field;
• managing insect populations that act as vectors for the virus;
• prompt removal and destruction of infected vines to minimize the inoculum source in the vineyard.