Grapevine flavescence dorée

Grapevine flavescence dorée is a highly destructive quarantine disease caused by the phytoplasma Candidatus Phytoplasma vitis. This systemic pathogen invades the phloem of the grapevine (Vitis vinifera), severely disrupting the translocation of sugars and nutrients throughout the vine, which eventually leads to a decline in plant vigor and crop yield.

Symptoms typically manifest as yellowing or reddening of leaves that curl downwards, characteristic stunting of shoot growth, and necrosis of the rachis, causing clusters to wither before harvest. Affected vines often fail to lignify, resulting in high susceptibility to winter freeze injury and eventual death of the entire plant.

The transmission of the disease is mediated primarily by the leafhopper Scaphoideus titanus, an insect vector that acquires the pathogen while feeding on infected vines. After a mandatory incubation period within the insect, the phytoplasma becomes transmissible to healthy vines during the leafhopper's subsequent feeding events, completing the biological cycle.

Environmental conditions, particularly warm temperatures, play a critical role in the rapid expansion of the disease, as they enhance the population dynamics and activity of the vector. Outbreaks can occur rapidly when infested nurseries distribute contaminated stock or when local leafhopper populations migrate from abandoned vineyards into healthy blocks.

Management strategies are focused on the strict implementation of quarantine measures, the use of certified pathogen-free nursery stock, and intensive vector control. Regular surveillance of vineyards for the presence of Scaphoideus titanus, followed by timely insecticide applications, is the cornerstone of keeping this disease under control and preventing economic devastation.

• Use of strictly certified propagation material.
• Monitoring leafhopper populations with yellow sticky traps.
• Removal and destruction of infected symptomatic vines.
• Chemical control targeting larval stages of the vector.