Neighbour-joining tree for the 658 prunus accessions. The tree was rooted using one wild relative species ‘Guang He Tao’ (Prunus mira. Koehne.) as outgroup. Bootstrap support values greater than 80% are shown in blue on the branches. Circled numbers beside the tree nodes indicate the 8 major groups. The colored parentheses indicate the clusters inferred by STRUCTURE analysis of 5 populations. The population ID are noted on the right. Accessions in different colors indicate they were assigned to corresponding populations. Unstructured accessions are in red.