LMU Munich, Department of Biology, Genetics, Grosshaderner Strasse 4, D-82152 Martinsried, Germany.
New Phytol. 2010 Jul;187(2):461-474. doi: 10.1111/j.1469-8137.2010.03262.x. Epub 2010 Apr 23.
*Currently, no official DNA barcode region is defined for the Fungi. The COX1 gene DNA barcode is difficult to apply. The internal transcribed spacer (ITS) region has been suggested as a primary barcode candidate, but for arbuscular mycorrhizal fungi (AMF; Glomeromycota) the region is exceptionably variable and does not resolve closely related species. *DNA barcoding analyses were performed with datasets from several phylogenetic lineages of the Glomeromycota. We tested a c. 1500 bp fragment spanning small subunit (SSU), ITS region, and large subunit (LSU) nuclear ribosomal DNA for species resolving power. Subfragments covering the complete ITS region, c. 800 bp of the LSU rDNA, and three c. 400 bp fragments spanning the ITS2, the LSU-D1 or LSU-D2 domains were also analysed. *Barcode gap analyses did not resolve all species, but neighbour joining analyses, using Kimura two-parameter (K2P) distances, resolved all species when based on the 1500 bp fragment. The shorter fragments failed to separate closely related species. *We recommend the complete 1500 bp fragment as a basis for AMF DNA barcoding. This will also allow future identification of AMF at species level based on 400 or 1000 bp amplicons in deep sequencing approaches.
目前，真菌尚未定义官方的 DNA 条码区域。COX1 基因 DNA 条码难以应用。内部转录间隔区（ITS）已被提议作为主要条码候选者，但对于丛枝菌根真菌（AMF；Glomeromycota），该区域的变异性异常大，无法解决密切相关的物种问题。对 Glomeromycota 的几个系统发育谱系的数据集进行了 DNA 条码分析。我们测试了一个跨越小亚基（SSU）、ITS 区和大亚基（LSU）核核糖体 DNA 的约 1500bp 片段的物种分辨率。还分析了涵盖完整 ITS 区、LSU rDNA 的约 800bp 和三个约 400bp 片段，跨越 ITS2、LSU-D1 或 LSU-D2 结构域。条码间隙分析并未解决所有物种问题，但基于 1500bp 片段的邻接法分析，使用 Kimura 双参数（K2P）距离可以解决所有物种问题。较短的片段无法分离密切相关的物种。我们建议使用完整的 1500bp 片段作为 AMF DNA 条码的基础。这也将允许未来基于深度测序方法中的 400 或 1000bp 扩增子在物种水平上鉴定 AMF。
