| Title | Chloroplast phylogeographic analysis guides the source tracing and conservation strategies of the endangered Magnolia kwangsiensis |
| Author | Shanyuan, W. E. N. |
| Publication | GENETIC RESOURCES AND CROP EVOLUTION |
| Year | 2026 |
| Volume | 73 |
| Issue | 7 |
| Corresponding Author | Qiaoming, LI |
| Abstract | Protecting genetic diversity is essential to reduce extinction risks during the global biodiversity crisis. Plastome-based phylogeographic screening provides an efficient means to characterize maternally inherited variation and trace the maternal sources of ex-situ collections. For karst endemic species such as the endangered tree Magnolia kwangsiensis Figlar & Noot., maternal source tracing can reveal whether existing ex-situ collections represent the geographically structured plastid diversity sampled in the wild. However, the maternal origins and plastid representativeness of existing ex-situ collections remain unverified. To rapidly and reliably assess the conservation genetics of the species, this study introduced an efficient approach by extracting and assembling 100 complete chloroplast genomes directly from whole-genome sequencing (WGS) data. The analysis reveals that M. kwangsiensis exhibits a clear spatial structure, dividing into two geographically distinct maternal plastid lineage groups. Crucially, maternal source tracing reveals that all five South China Botanical Garden (SCBG) accessions belong to the eastern maternal lineage group and do not represent the more diverse plastid lineages sampled in Yunnan. Because these results derive from a single maternally inherited locus, the two regional maternal lineage groups are treated as candidate ESUs pending nuclear confirmation. This plastome-based approach therefore offers a rapid means of tracing maternal sources and identifying geographic gaps in ex-situ collections. |
