Disease resistance gene pyramiding is a widely used strategy to enhance durability. Marker-assisted selection (MAS) was applied pyramide the alleles Run1 and Ren3, which confer against grape powdery mildew (Erysiphe necator). Two F1 full-sibs carrying Ren3 in heterozygosity were selfed develop breeding populations analysis. From 637 genotyped plants, 313 (50.6%) had pyramided. Seven (1.1%) of t...