ML tree obtained using nuclear sequences.

Vitis accessions (codes in S1 Table) were grouped in separated clades: EA (East Asia, blue), EU (Europe, spring green: V. vinifera subsp. vinifera, dark green: V. vinifera subsp. sylvestris), NA1 (North America 1, orange), NA2 (North America 2, red), V. californica (brown) and M. rotundifolia (grey). Known hybrids were figured in pink (CHA, DOA1, LAB). The tree is drawn to scale, with branch lengths measured by the number of substitutions per site. The percentage of trees in which the associated accessions clustered together is shown at nodes with threshold at 70 and 90%.