降香黄檀的DNA条形码鉴定研究

DNA Barcoding the Plants of Dalbergia odorifera

DNA条形码技术是利用基因组中一段短的标准序列进行物种鉴定及探索其亲缘进化关系的方法。本研究对采自海南不同地区降香黄檀5个居群24份样品的psbA-trnH、rbcL、核ITS及ITS2序列进行PCR扩增和测序,比较各序列扩增和测序效率。采用BLAST1和邻接(NJ)法构建系统聚类树方法评价不同序列的鉴定能力。结果表明ITS2在所研究的材料中具有最高的扩增和测序效率,而ITS扩增效率较低。ITS2完整序列在区分黄檀属不同种间差异具有较大优势。因此可利用ITS2从分子水平区分降香黄檀与其他混伪种。

DNA barcoding is a technique of species identification and phylogenetic analysis by using DNA se- quences from a small fragment of the genome. In the study,we used this technique to identify 24 Dalbergia odorifera samples of five populations from different regions of Hainan province and selected psbA-trnH, rbcL, nuclear ITS, and ITS2 sequences to compare the amplification and sequencing efficiency. We constructed phylogenetic tree by BLAST1 and NJ methods to evaluate the identification ability of different sequences. Our results showed that ITS2 had the highest amplification and sequencing efficiency among all the studied materials,while ITS had lower amplifi- cation efficiency. The complete sequence of ITS2 demonstrated greater advantages in distinguishing different strains of Dalbergia odorifera. Our study also demonstrated the efficacy of ITS2 to distinguish between Dalbergia odorifera and other adulterants species at the molecular level.