S20 - Session P3 - Etiology and epidemiology of pathogens causing grapevine trunk diseases in vineyards under climatic conditions of Quebec, Canada

Authors: Caroline Provost *, Alexander Campbell

Grapevine trunk diseases (GTD) are considered very damaging to the sustainability of the wine heritage in all the major wine regions of the world. A multitude of fungi are responsible for these diseases and attack the perennial organs of the vine, which causes the death of the plant in the short or medium term. GTD can affect young plantations and ageing vineyards; in both cases, the risks of these diseases are increasing in vineyards in Quebec, Canada. In addition, with the climatic changes anticipated over the years, new grape varieties will be established in Quebec, thus promoting the introduction of vine varieties more susceptible to GTD in our vineyards. Climate change can promote the spread of these diseases, including higher temperatures and heavy rainfall. The main objective of this project was to acquire knowledge on the etiology and epidemiology of grapevine trunk diseases in the vineyards of Quebec, Canada. The project was divided into two parts: 1) an assessment of the presence and distribution of GTD across Quebec was carried out according to various criteria (region, grape variety, age of the vineyard, and part of the plant); and 2) the epidemiology of GTD was studied under Quebec conditions using spore sensors. The results demonstrated the presence of several GTD in Quebec vineyards. Fungi causing excoriose, eutypia, black dead arm, esca and black foot have been identified. The knowledge acquired will make it possible to establish the epidemiology of GTD under Quebec's climatic conditions. In addition, it will be possible to suggest cultural practices to reduce the spread of GTD in Quebec, Canada.