Incongruence between nuclear and chloroplast DNA phylogenies in pedicularis section Cyathophora (Orobanchaceae)

PLoS One. 2013 Sep 19;8(9):e74828. doi: 10.1371/journal.pone.0074828. eCollection 2013.

Abstract

Pedicularis section Cyathophora is a monophyletic group characterized by perfoliate leaf and/or bract bases at each node. This section comprises four series, corresponding to four general corolla types of Pedicularis, i.e. toothless, toothed, beaked and long-tubed corollas. In this study, we aim to reconstruct a comprehensive phylogeny of section Cyathophora, and compare phylogenetic incongruence between nuclear and chloroplast datasets. Sixty-seven accessions belonging to section Cyathophora and 9 species for other Pedicularis were sampled, and one nuclear gene (nrITS) and four chloroplast genes (matK, rbcL, trnH-psbA and trnL-F) were sequenced. Phylogenetic analyses show that the topologies and networks inferred from nrITS and the concatenated chloroplast datasets were incongruent, and the nrITS phylogenies and network agreed with the morphology-based taxonomy to some degree. The chloroplast genome of two Sichuan samples of P. cyathophylloides (E4 and E5) may show introgression from an ancestor of P. cyathophylla. Neither the nrITS dataset nor the concatenated chloroplast dataset were able to adequately resolve relationships among species in the series Reges; this is most likely due to incomplete lineage sorting and/or introgression/hybridization. The nrITS phylogeny indicates the beakless (toothed and toothless) and beaked galeas may have evolved independently within section Cyathophora, and the chloroplast phylogeny reveals that the long corolla tube with beaked galea is derived from the short one.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • DNA, Chloroplast*
  • DNA, Plant*
  • DNA, Ribosomal Spacer / genetics
  • Geography
  • Pedicularis / classification*
  • Pedicularis / genetics*
  • Phenotype
  • Phylogeny*

Substances

  • DNA, Chloroplast
  • DNA, Plant
  • DNA, Ribosomal Spacer

Grants and funding

This study is supported by grants from the National Natural Science Foundation of China (31200185), the West Light Foundation of the Chinese Academy of Sciences, the National High-tech Research & Development Program of China (2012AA021801), the National Science and Technology on Basic Research Program (2013FY112600), the Key Research Program of the Chinese Academy of Sciences (KJZD-EW-L07), the Large-Scale Scientific Facilities of the Chinese Academy of Sciences (2009-LSF-GBOWS-01), and the National Key Basic Research Program of China (2014CB954100). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.