Based on a subset of 94 individuals, three SSR markers, VVIB22 (Merdinoglu et al. 2005), VrZAG62 (This et al. 2004), and VVMD7 (Bowers et al. 1996) located on chromosome 7, near the Rda2 locus, were confirmed to be linked to Rda2 (Table 4). SC8_0040_088 (Jaillon et al. 2007) was the only SSR marker near Rda1 in the PN40024 reference (18.9 Mbp), but was homozygous in the resistant parent V. cinerea B9 (358 bp) and thus non-informative in the progeny.Table 4SSR allele sizes in linkage with the Rda2 locusSSR markerPhysical location (Mbp)‘Horizon’V. cinerea B9Allele size (bp)p valueAllele size (bp)p valueVVIB223.10157/1391.8 × 10−12144/1600.068VrZAG621.78180/2021.8 × 10−12174/1880.650VVMD71.17237/2351.2 × 10−11231/231naAlleles associated with resistance to Phomopsis cane lesions from ‘Horizon’ are indicated in bold. Linkage was determined by χ2 test over a subset of 66 progeny from ‘Horizon’ × Vitis cinerea B9