含岩白菜素药用植物DNA条形码的鉴定研究

Identification of DNA barcode of medicinal plants containing bergenin

目的评价以ITS2和psbA-trnH序列作为DNA条形码对含有岩白菜素药用植物的鉴定。方法采集了9份含有岩白菜素和13份不含岩白菜素的药用植物样本,扩增所有样品的ITS2与psbA-trnH序列,并从Gen Bank下载含岩白菜素和不含岩白菜素药用植物的ITS2与psbA-trnH序列,计算种间和种内遗传距离,并构建NJ系统进化树评价序列的鉴定能力。结果所有样本的ITS2序列和psbA-trnH序列的扩增及测序成功率都为100%,含岩白菜素药用植物的ITS2序列的种间遗传距离为0.6455,远大于种内遗传距离(0.0384)。ITS2与psbA-trnH均能鉴定含有岩白菜素与不含有岩白菜素药用植物,但ITS2在鉴定不同科的含有岩白菜素药用植物的效率优于psbA-trnH序列。结论以ITS2序列为主,psbA-trnH序列为辅的DNA条形码组合可用于含岩白菜素药用植物的鉴定,为含岩白菜素的药用植物种质资源的整理、标准化与保护等提供了有效的基础数据。

OBJECTIVE To evaluate the identification of bergenin containing medicinal plants using ITS2 and psbA-trnH sequences as DNA barcodes. METHODS Nine samples of bergenin and 13 samples of bergenin free medicinal plants were collected,and the ITS2 and psbA-trnH sequences of all samples were amplified. The ITS2 and psbA-trnH sequences of bergenin and bergenin free medicinal plants were downloaded from Gen Bank,the genetic distance between species and within species was calculated,and the evaluation ability of NJ phylogenetic tree was constructed. RESULTS The success rate of amplification and sequencing of ITS2 sequence and psbA-trnH sequence was 100%. The interspecific genetic distance( 0. 6455) of ITS2 sequence of bergenin containing medicinal plants was far greater than that of intraspecific genetic distance( 0. 0384). Both ITS2 and psbAtrn H could identify bergenin containing and non bergenin containing medicinal plants,but ITS2 was better than psbA-trnH sequence in identifying different families of bergenin containing medicinal plants. CONCLUSION The combination of DNA barcode with ITS2 as the main sequence and psbA-trnH as the auxiliary sequence can be used for the identification of medicinal plants containing bergenin,which provides effective basic data for the sorting,standardization and protection of medicinal plant germplasm resources containing bergenin.