广东省主要红树林植物DNA条形码评价

为评估DNA条形码对鉴定红树林植物的通用性和有效性,在广东红树林分布区域共计采集红树林植物16科22属23种,共144个样品,并进行DNA条形码测序。结果表明:选择的rbcL、matK和trnH-psbA 3个DNA片段的PCR扩增成功率分别为100%、80.29%±8.49%、99.38%±1.25%。测序成果率最高为rbcL 100%,trnH-psbA次之94.57%±5.06%,matK最低75.04%±6.26%。表明rbcL和trnH-psbA片段在红树林群落中都具有较好的通用性。应用BLAST和NJ Tree两种方法计算红树植物的物种识别率。BLAST结果表明,单片段中trnH-psbA的物种识别率最高,为84.48%±12.09%,rbcL次之,matK最低。NJ Tree分析显示单片段中rbcL的物种识别率最高,为66.65%±17.35%;trnH-psbA片段次之,matK片段最低。两张分析方法都显示多个片段组合使用时,rbcL或trnH-psbA是提高物种平均识别率的主要片段。利用单片段rbcL即可获得平均节点支持率最高的红树植物系统发育树,且能准确区分不同树种。trnH-psbA片段可以识别rbcL片段不能识别的物种,可以作为补充片段。综合比较,推荐rbcL、trnH-psbA作为红树林植物DNA条形码片段。

Assessment of Major Mangrove Plants from Guangdong Province Using DNA Barcode

To evaluate the effectiveness of DNA barcoding for identifying mangrove species,we sampled 144 individuals representing 23 species,22 genera,and 16 families in Guangdong Province.The success rate of PCR amplification of rbcL,matK and trnH-psbA were 100%,80.29%±8.49%,and 99.38%±1.25%,and the highest rate of DNA sequencing were 100%with rbcL,followed by 75.04%±6.26%with matK,94.57%±5.06%with trnH-psbA.Both rbcL and trnH-psbA are universal for mangroves in Guangdong Province.BLAST and NJ Tree were used to calculate species identification of mangrove.The highest success rate of species identification was 84.48%±12.09%with trnH-psbA,followed by rbcL and matK by BLAST.Also the highest success rate of species identification was 66.65%±17.35%with rbcL,followed by trnH-psbA and matK,by NJ Tree.Either BLAST results or NJ Tree results also showed rbcL or trnH-psbA were the main fragments to improve the average recognition rate of species when multiple combinations of fragments were used.When the phylogenetic relationships were constructed with random fragment or combinations,the optimal evolutionary tree with highest supporting values was established using the rbcL fragment in mangroves.Therefore,rbcL and trnH-psbA were the most suitable DNA barcode fragments for species identification in mangrove plants.