Failure of DNA barcoding in discriminating <i>Calligonum</i> species

We tested the effectiveness of four DNA barcoding markers (rbcL, matK, ITS and trnLF region) for land plants in identifying Calligonum species. High quality sequences were obtained for rbcL, matK and trnLF with the universal primers whereas ITS sequences were of poor quality. RbcL and matK were highly conservative and failed in species discrimination. When rbcL, matK and trnLF were combined, the species resolution was up to 6.25%. Low sequence variation resulted in poorly resolved tree topologies. Among the sixteen sampled species, only three were recovered as a monophyletic group. Our results show that although DNA barcoding is an important tool for species identification, it fails in discriminating Calligonum species. Further research will be needed to develop markers capable to discriminate species in this taxonomy complicated and recently diverged genus.

Перевод пока недоступен