Grapevine cultivation, heavily reliant on pesticides due to susceptibility to powdery mildew (PM), has significant human and environmental impacts. With limited alternatives to pesticides, plant breeding is crucial. DEMETRA aims to understand grapevine response to PM through genetic analysis of 246 genotypes using SNPs-genotyping, phenotyping and QTL analysis. In the second year, selected grapes will undergo in vitro fungal inoculation and RNA sequencing to study stress response mechanisms. This research will inform breeding programs for disease-resistant grape varieties.