竹亚科叶绿体DNA条形码筛选

Selection of Potential Plastid DNA Barcodes for Bambusoideae( Poaceae)

竹亚科是一个形态上鉴定困难且易于混淆的类群。DNA条形码技术为这一类群的鉴定提供了一个辅助手段。核心条形码(rbcL+matK)在竹亚科中的鉴别率很低,因此,有必要针对竹亚科筛选有效的DNA条形码片段。本研究根据已发表的竹亚科叶绿体基因组序列,筛选出16个片段,包括1个基因片段和15个基因间隔区,选取青篱竹族和箣竹族的10属22种30个个体,进行引物通用性、测序成功率和变异位点分析。研究结果表明:(1)引物具有较高的扩增成功率,但部分片段中由于存在poly结构造成测序失败;(2)片段中的插入/缺失可以编码,作为信息位点;(3)trnG-trnT(t)具有最多变异位点,建议可作为竹亚科优先选择的DNA条形码;(4)在开展不同类群的DNA条形码和分子系统学研究时,可以按照"trnG-trnT(t)+X"的方式选择合适的叶绿体DNA片段。

Bamboos are a taxonomically difficult group. DNA barcoding provides another supplementary method for the bamboo identification. The core DNA barcodes （rbcL＋matK） have quite low discriminatory power in bamboos, therefore, it is crucial to select effective DNA bareodes for bamboos. We scanned the entire chloroplast genomes that were published in Bambusoideae in order to search highly variable regions. Sixteen regions were selected including one coding region and 15 intergenie spacers, and the universality, sequencing success rates, and the variable char- acters were testified in 30 taxa of 22 species in 10 genera of Arundinarieae and Bambuseae. The results indicated that （ 1 ） the amplification success rates were high for each region, but there were some problems in sequencing for some regions due to poly-struetures; （2） indels should be coded as informative characters; （3） the region trnG-trnT （t） was the most variable one among the 16 regions and it was suggested as the prior candidate DNA barcode in Bambusoideae; （4） the combination ＂trnG-trnT（t） ＋X＂ can be used in DNA bareoding and molecular-phylogeny reconstruction study of bamboos.