The project aims to elucidate the genetic basis of grapevine resistance/susceptibility to powdery mildew (PM) using a multi-omics approach focused on marker-trait associations. At the end of the project, we will be able to identify molecular markers and candidate genes useful to develop marker-assisted breeding schemes, enabling the selection and breeding of grape varieties with enhanced resistance to PM, thereby reducing pesticide reliance and environmental impact. The scientific objectives of DEMETRA are:

1. Phenotyping and Genotyping: Conduct extensive phenotyping of a large collection of grape genotypes for PM response using field protocols, and perform SNP-genotyping to achieve a marker density of at least 18K SNPs across 19 chromosomes.
2. QTL Analysis: Integrate genotypic and phenotypic data to perform QTL analysis using two approaches: single-family QTL analysis for FS-POP and genome-wide association study (GWAS) for GC-POP, to identify genetic markers linked to PM resistance/susceptibility.
3. Selection of Representative Genotypes: Identify and select representative genotypes displaying resistance or susceptibility to PM based on QTL analysis results, for further detailed study.
4. In Vitro PM Infection: Conduct in vitro PM infection experiments on selected genotypes over a time course to observe the infection process and collect infected leaf samples for deeper analysis.
5. Transcriptomic and Epigenomic Analyses: Perform transcriptomic and epigenomic analyses on infected leaves to investigate the genetic and epigenetic mechanisms underlying resistance/susceptibility to PM, including gene expression profiling and miRNA-mediated regulation.