Figure 2

Phylogenic tree of 39 Populus species based on an alignment of 76 chloroplast coding genes using the ML method. Two Salix species were used as out-groups. The number above each node indicates the BS support value for that clade.
Phylogenic tree of 39 Populus species based on an alignment of 76 chloroplast coding genes using the ML method. Two Salix species were used as out-groups. The number above each node indicates the BS support value for that clade.