Jardín Botánico Canario "Viera y Clavijo"-Unidad Asociada CSIC, Cabildo de Gran Canaria, Apartado de correos 14 de Tafira Alta, 35017, Las Palmas de Gran Canaria, Spain; Fundación Canaria Amurga Maspalomas, Avda. Tirajana 39, II 6, 35100, San Bartolomé de Tirajana, Spain.
Mol Ecol Resour. 2015 Jan;15(1):42-56. doi: 10.1111/1755-0998.12292. Epub 2014 Jul 3.
We use a comprehensive subset of Canarian angiosperms corresponding to 23 families, 35 genera and 60 Canarian endemic taxa to test whether this flora is suitable to taxonomic identification with the two proposed plant DNA barcode sequences and whether these sequences may reveal the existence of cryptic species overlooked by morphology. The rate of discrimination success between the insular congeneric samples using the rbcL+matK combination and a 'character-based' approach (where we use only the combination of nucleotide positions in an alignment that allows unambiguous species identification) is higher (82.29%) than that obtained with the 'distance-based' approach (80.20%) used by the CBOL Plant Working Group in 2009 and also when compared with tests conducted in other floras. This suggests that the molecular identification of the Canarian endemic flora can be achieved as successfully as in other floras where the incidence of radiation is not as relevant. The facts that (i) a distance-based criterion was unable to discriminate between congeneric and conspecific comparisons and (ii) only the character-based discrimination criterion resolved cases that the distance-based criterion did not, further support the use of a character discrimination approach for a more efficient DNA barcoding of floras from oceanic islands like the Canaries. Thus, a barcoding gap seems not to be necessary for the correct molecular characterization of the Canarian flora. DNA barcodes also suggest the possible existence of cryptic taxa to be further investigated by morphology and that the current taxonomic status of some of the taxa analysed may need revision.
我们使用了加那利群岛被子植物的一个综合子集，对应 23 个科、35 个属和 60 个加那利群岛特有分类群，以测试该植物群是否适合使用两种拟议的植物 DNA 条码序列进行分类鉴定，以及这些序列是否可以揭示形态学忽略的隐种存在。使用 rbcL+matK 组合和基于“特征”的方法（我们仅使用允许明确物种鉴定的比对中核苷酸位置的组合）对岛屿同种样本进行区分的成功率（82.29%）高于 2009 年 CBOL 植物工作组使用的“基于距离”的方法（80.20%），也高于在其他植物区系中进行的测试。这表明，加那利群岛特有植物群的分子鉴定可以像在其他辐射发生率不那么相关的植物区系中一样成功。事实是（i）基于距离的标准无法区分同属和同种比较，（ii）只有基于特征的区分标准才能解决基于距离的标准无法解决的问题，这进一步支持了使用特征区分方法来更有效地对加那利群岛等海洋岛屿的植物区系进行 DNA 条码编码。因此，对于加那利群岛植物群的正确分子特征描述，似乎不需要条形码间隙。DNA 条码还表明可能存在需要进一步通过形态学研究的隐种，并且所分析的一些分类群的当前分类地位可能需要修订。
