2.1 | Sampling and DNA extraction
A total of 271 samples were collected from 15 sites in the Qinling
Mountains of China (Figure 1). Of these locations, SZA and SYX are
located in fragmented landscape, which are surrounded by roads, railway
line and villages. Moreover, Cymbidium goeringii , Cymbidium
ensifolium , Cymbidium kanran and Cymbidium sinense were
collected as outgroups. DNA was extracted using Tiangen Extraction Kit
(Beijing, China).