山麦冬及其近缘种DNA条形码研究

Analysis of Liriope spicata and Its Related Species Based on DNA Barcoding Technique

通过分析山麦冬及其近缘种cpDNA trnL-F、psbA-trnH间隔区序列特点,探讨trnL-F、psbA-trnH序列作为山麦冬及其近缘种DNA条形码的潜力。分别对两者进行PCR扩增后,并进行纯化测序。其中山麦冬及其近缘种9个物种18个样品的trnL-F序列长度为355～356 bp,在山麦冬属内序列完全一致,但在沿阶草属中存在特异变异位点,可对麦冬与沿阶草两物种进行鉴别。而psbA-trnH序列长度为543～544 bp,仅在麦冬中存在特异鉴别位点。结果表明,trnL-F、psbA-trnH序列由于进化速率低、保守性强,仅适合麦冬类植物属间鉴别的DNA条形码,而在属下水平的应用有一定的局限。

To discuss the potential of cpDNA trnL-F and psbA-trnH as DNA barcode of Liriope spicata （Thun- berg） Loureiro and its related species, cpDNA trnL-F and psbA-trnH sequences were analysed. These two regions were respectively amplified by PCR and then purified and sequenced successfully. The results showed that the lengths of trnL-F sequences in 18 plant samples belonging to9 species of liriopogons varied from 355 to 356 bp. There was no difference in the trnL-F of various species of liriope, but some specifically variable sites were found in this fragment, which led to the identification between Ophiopogon japonicus （Thunb.） Ker-Gawl and Ophiopogon bodinieri Levl. The length of psbA-trnH region was 543 -544 bp, there were only some identification sites in O. japonicus （Thunb.） Ker-Gawl. Because of the low rate of evolution and the high conservation, these two cpDNA spacer regions could be only appropriate as a DNA barcode to identify liriopogons at generic level, but there is a degree of limit at lower taxonomic level.