OBJECTIVE To identify Magnoliae Flos and its related species using DNA barcoding technology, so as to establish a rapid, accurate and convenient method for identification of Magnoliae Flos.
METHODS Genomic DNA of 21 Magnoliae Flos and their related species were extracted, and ITS, ITS2, psbA-trnH, matK and rbcL gene sequences were amplified and sequenced. MEGA7.0 software was used for sequence comparison, and the intraspecific and interspecific genetic distance was calculated based on Kimura-2-Parameter (K2P) model to evaluate Barcoding gap, and the NJ phylogenetic trees were constructed to react identification results.
RESULTS Among the 5 primers, psbA-trnH and matK could normally amplify the target gene, and the success rate of them was higher than 98%, while the success rate of rbcL sequencing was 38.1% only. The matK sequence had the highest number of variation sites, and psbA-trnH had the most prominent species discriminatory on Barcoding gap analysis relative to matK and rbcL. The NJ phylogenetic tree showed that psbA-trnH+matK barcode sequence could accurately identify 9 varieties, and distinguish Magnoliae Flos and its relatives. In addition, we applied it to the molecular identification of Magnolia grafting rootstocks for the first time.
CONCLUSION The sequence combination of psbA-trnH+matK can realize the accurate identification of Magnoliae Flos, and can be applied to the rapid identification of Magnolia grafting rootstocks.
DownLoad: