[Identification of Chrysanthemum indicum in different geographical populations and Ch. morifolium based on DNA barcodes of psbA-trnH,matK and trnL].

DNA barcode technology was used to establish a rapid identification method of Chrysanthemum indicum and Ch. morifolium based on psbA-trn H,mat K and trn L sequences. The total DNA was extracted from 21 samples collected,and the psbA-trn H,mat K,trn L sequences were amplified by PCR and sequenced. The information of these sequences were obtained. We aligned all 63 sequences,calculated the intraspecific and interspecific distances,analysed the SNPs distribution of psbA-trn H+mat K+trn L combination sequences and constructed the Neighbor-joining( NJ) Tree,using MEGA 7. 0. The results showed that the genetic distances of Ch. indicum,Ch. indicum( Juhuanao)and Ch. morifolium were overlapped. The SNPs analysis of psbA-trn H+mat K+trn L combination sequences showed that there were 19 nucleotide polymorphism loci( SNPs) and nine parsim-informative sites in the combination sequences. In addition,Ch. indicum showed more obvious sequence polymorphism than those of Ch. indicum( Juhuanao) and Ch. morifolium. The psbA-trn H sequences showed obvious length variation.The NJ Tree showed that Ch. morifolium numbered C2-C5 were clustered into a single subbranch with a bootstrap value of 62%,and Ch.morifolium could be distinguished from Ch. indicum and Ch. indicum( Juhuanao). Moreover,Ch. indicum numbered Z9 and Z10 collected from Gansu province were singly clustered into one branch with a bootstrap value of 77%. It was also found that the changes of psbA-trn H and trn L sequences information of Ch. indicum samples from the northwest were obviously related to the geography and environment. Moreover,Ch.indicum and Ch. indicum( Juhuanao) had obvious differentiation,were also regarded as the evolutionary sources of Ch. morifolium. Therefore,psbA-trn H+mat K+trn L combination sequences as DNA barcode can identify Ch. indicum and Ch. morifolium accurately and rapidly,which provides an important basis for germplasm resources identification and species identification.