Authentication of Citrus Medica L.Var.Sarcodactylis Swingle and Its Related Species Based on DNA Barcoding Technique
Objective To screen the appropriate DNA barcoding sequences from commonly used DNA barcodes for authentication of Citrus medica L.var.Sarcodactylis Swingle and its related species,and briefly discuss their genetic relationship.Methods The ITS2,psbA-trnH,matK and rbcL sequences of C.medica var.Sarcodactylis and C.medica were amplified by using four pairs of universal primers.And then,some related DNA sequences with higher similarities were downloaded from GenBank and Barcode of Life Databases.Sequence alignments,genetic distance calculation and construction of phylogenetic trees were conducted by using MEGA-X software.The ITS2 secondary structures of all species were predicted by using ITS2 database,and the difference among the ITS2 secondary structures were compared.Results There was little genetic difference between C.medica var.Sarcodactylis and C.medica.The NJ phylogenetic tree gathered into one branch.The ITS2 secondary structures of C.medica var.Sarcodactylis is consistent with that of C.medica.None of the four sequences could distinguish C.medica from C.medica var.Sarcodactylis.Among them,mat K sequence was predominant in the authentication of C.medica var.Sarcodactylis.The psbA-trnH sequence exhibited higher interspecific differences among C.medica var.Sarcodactylis and some other distantly related species of Citrus.Conclusion The matK and psbA-trnH sequences can be used as potential DNA barcodes to distinguish C.medica var.Sarcodactylis from its related species with genetic distances.The closest genetic relationship is found between C.medica var.Sarcodactylis and C.medica.Therefore,it is still necessary to screen other DNA fragments to distinguish C.medica var.Sarcodactylis and C.medica.
万方数据
维普
