Interspecific hybrid identification of Vitis aestivalis-derived ‘Norton’-based populations using microsatellite markers

• Vitis aestivalis-derived ‘Norton’-based mapping populations constructed.
• Identification of interspecific hybrids using molecular marker demonstrated.
• New marker alleles for Vignoles, a French–American hybrid, developed.

The Vitis aestivalis-derived ‘Norton’ is one of the very few commercial red grape varieties that can be grown in regions with high disease pressure and cold temperatures in winter and spring where V. vinifera is difficult to grow. This study began with the objectives of generating interspecific hybrids of Norton and V. vinifera (Cabernet Sauvignon, Pinot Noir, Syrah, and Merlot) in order to combine the disease resistance and cold hardiness characters of V. aestivalis with the excellent wine quality of V. vinifera. Norton grapes were also crossed with the Vitis interspecific hybrid ‘Vignoles’ for the same reason. The true hybrids obtained from all of the crosses were identified using microsatellite markers. A high percentage of hybrids (70–92%) were obtained in all crosses except Norton × Merlot (17%). Results demonstrate the reliability of SSR markers for Norton-based interspecific hybrid identification.