title: [Study on genetic polymorphism of Platycodon grandiflorum based on barcoding of ITS2].
abstract: OBJECTIVE
  ITS2 of DNA barcoding was used to study genetic polymorphism of Platycodon grandiflorum.
  
  
  METHODS
  Total genomic DNA was isolated from P. grandiflorum. PCR was used to amplified the region of internal transcribed spacer 2 (ITS2), and PCR products were sequenced. The sequences of ITS2 were analyzed and compared by Clustal. The intraspecies genetic distance was calculated based on Kimura 2-parameter model by using MEGA 5.05. The ITS2 sequence of Codonopsis pilosula was used as the outreach value for plants of the genus, and the phylogenic tree used constructed by Neighbor-Joining (NJ) method.
  
  
  RESULTS
  The K2-P's genetic distance of all samples were ranged from 0 to 0.930. The K2-P's genetic distance of samples at the same area were ranged from 0 to 0.178. The K2-P's genetic distance of samples at different areas were ranged from 0.735 to 0.930. The analytical result showed that the degree of genetic variation were heavy in intraspecies of P. grandiflorum and significantly correlated with geographical location.
  
  
  CONCLUSIONS
  The DNA barcoding of ITS2 can applied to study the intraspecific genetic diversity, it provides a reference for further development of DNA barcoding technology applications.
authors.forename: Bo
authors.initials: B
authors.lastname: Wu
authors.forename: Yong-bo
authors.initials: YB
authors.lastname: Li
authors.forename: Jiang-bo
authors.initials: JB
authors.lastname: Rao
authors.forename: Jin-xiang
authors.initials: JX
authors.lastname: Zeng
authors.forename: Ji-xiao
authors.initials: JX
authors.lastname: Zhu
authors.forename: Xiang-xiang
authors.initials: XX
authors.lastname: Fang
authors.forename: Fu-qing
authors.initials: FQ
authors.lastname: Liu
authors.forename: Hong-ze
authors.initials: HZ
authors.lastname: Li
authors.forename: Feng-yu
authors.initials: FY
authors.lastname: Han
authors.forename: Guo-yue
authors.initials: GY
authors.lastname: Zhong
mesh_terms: D002681:China; D058893:DNA Barcoding, Taxonomic; D018744:DNA, Plant / Q000235:genetics*; D021903:DNA, Ribosomal Spacer / Q000235:genetics*; D008969:Molecular Sequence Data; D010802:Phylogeny; D031238:Platycodon / Q000145:classification* / Q000235:genetics*; D011110:Polymorphism, Genetic
chemical_list: D018744:DNA, Plant; D021903:DNA, Ribosomal Spacer