Discovery of a Locus Associated with Susceptibility to Esca in Grapevine.

Esca is the most destructive and predominant grapevine trunk disease. The chronic infections and vine mortality caused by esca syndrome lead to huge economic losses and threaten the sustainability of vineyards worldwide. Esca is caused by numerous wood-decay and wood-decay-associated fungi, but its full etiology remains unclear due to the grapevine trunk disease complex, making effective control methods challenging. As differences in esca susceptibility have already been observed among grapevine varieties, we investigated the presence of genetic factors that can explain these variations using a Riesling × Gewurztraminer progeny. Thanks to the destructive phenotyping of a 16-year-old vineyard plot, we discovered that the Gewurztraminer variety carries on chromosome 1 a locus linked to variations in trunk necrosis associated with esca, which we have named (). Our study also suggests that there is a partial link between trunk vigor and necrosis due to esca. To our best knowledge, is the first instance of the genetic factor identified as involved in the limitation of necrosis associated with grapevine esca. While the identification of alone may not provide a complete resolution of the issue, this discovery nonetheless represents a first step toward a genetic solution and paves the way for broader genetic investigations in the future.