Objective The study was carried out to develop new molecular markers and analyze the molecular phylogeny of Magnolia officinalis in Longshan Tree Farm, Lechang, Guangdong, with a view to facilitating subsequent researches on the selection of excellent plants and breeding of superior varieties.

Method Fourteen Magnolia officinalis (provenances from Jiangxi Province) individual plants collected from Longshan Tree Farm were used as tested materials. By using Primer BLAST on NCBI (https://www.ncbi.nlm.nih.gov), fixed primers of TRAP molecular markers were designed based on the sequences of M. officinalis cDNA in the GenBank. The fixed primers were matched with random primers (sequence related amplified polymorphism) to amplify genomic DNA and develop TRAP molecular markers. The electrophoretogram of TRAP markers and amplified products of M. officinalis SSR (Simple Sequence Repeat) were counted. Then, NTSYSpc2.10e was used for cluster analysis to discover the genetic diversity and phylogeny of fourteen M. officinalis resources.

Result Seven TRAP molecular markers showing good polymorphism and clear electrophoresis bands were successfully developed from seventy primer pairs formed by fourteen fixed primers and five random primers. The phylogenetic tree of M. officinalis plants was constructed. The genetic similarity coefficient of these M.officinalis plants was 0.75-0.88 and it was not the highest between mother plant and its offspring.

Conclusion M. officinalis was rich in genetic diversity and gene exchange was frequent in M. officinalis population. The newly developed TRAP molecular markers will facilitate identification of superior plants, breeding of excellent varieties and marker-assisted selection of M. officinalis in the future.