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Grapevine curettage was re-introduced in France in the early 2000s, and is important for facilitating recovery of plants from esca disease. This surgical practice involves removal of deadwood of vines with leaf symptoms, focusing on white rot generally observed at the centres of grapevine trunks. Assessment of the efficacy of this practice was initiated in the Bordeaux region in 2014. One ‘Sauvignon Blanc’ vineyard severely affected by esca was initially surveyed in the summer of 2014, to identify and treat vines with esca foliar symptoms. Annually thereafter, from 2014 to 2018, selected vine stocks were curetted. Two other ‘Sauvignon Blanc’ vineyards also displaying high levels of esca damage were added to the study in 2015 and 2016. Curettage treatments ceased in 2018, resulting in 11 trials (vineyard × year combinations). In total, 856 vines (422 curetted and 434 control vines) were then surveyed annually up to 2021, for assessments and comparisons of esca development. At each site, plants with esca symptoms recovered well after curettage: on average 85% of all curetted vines became asymptomatic the year immediately after the treatment. Six years after treatment, for curettage campaigns carried out in 2014 and 2015, more than half of the curetted vines were symptom-free, whereas

The re-emergence of Grapevine Trunk Diseases (GTDs), mainly Esca, has been observed in most of the world’s vineyards during the last two decades. Development of necrosis in grapevine wood, especially white-rot, is typically associated with Esca-diseased plants. One of the different methods being used in attempts to eradicate GTDs is curettage. This old cultural practice, which consists in surgically removing the necrotic wood, specifically white-rot, retaining only the non-necrotic tissue of Esca-diseased grapevine, is used in some European vineyards (Spain, France, Italy, Portugal), and is being increasingly reintroduced since 10 years ago in France. We, therefore, wanted to study the effect of curettage on vigour, fertility and berry quality, and year after year plant recovery. Our study synthetizes a 3-year experiment on Esca-diseased cv. Sauvignon blanc grapevines curetted in a commercial plot in the Bordeaux region. Asymptomatic control grapevines were compared to Esca-diseased grapevines without curettage (with typical foliar symptoms), and with curetted Esca-diseased grapevines (without foliar symptoms). Even if the curetted grapevines recovered lower vigour and fertility than the control plants, their grape berry quality was comparable, unlike for Esca-diseased grapevines. This cultural practice proved particularly effective in helping Esca-symptomatic grapevines to recover asymptomatic after treatment. Over time, curettage induces the resilience of grapevines, allowing them to recuperate their full physiological functioning, thereby compensating for Esca’s detrimental impact on berry quality.