Fig 4. Principal components analysis of leaf morphological traits of 116 jujube varieties from 33 sites in northern China.

All jujube varieties are divided into three groups: GROUP 1 (filled squares), GROUP 2 (filled triangles up), and GROUP 3 (filled circles). The seven provinces where the 33 sampling sites are located are represented by numbers for the sake of brevity. Members of GROUP 1 were mainly from Hebei, Shandong, Henan, southern Shanxi and central Shaanxi Provinces; Members of GROUP 2 were mainly from northwest Shanxi and northeast Shaanxi. Members of GROUP 2 were mainly from Gansu and Ningxia Provinces.