Chloroplast Phylogeny Indicates that Bryophytes Are Monophyletic

TLDR

Opinions on the basal relationship of land plants vary considerably, and no phylogenetic tree with significant statistical support has been obtained. We report phylogenetic analyses using 51 chloroplast genes from 20 representative green plant species and propose bryophyte monophyly as the best hypothesis. We performed phylogenetic analyses using 51 chloroplast genes from 20 representative green plant species. The amino‑acid‑based analyses show that extant bryophytes form a monophyletic group with high confidence and are likely sister to vascular plants, while nucleotide analyses could not resolve the basal relationship and bryophyte monophyly is not rejected by other data sets.

Abstract

Opinions on the basal relationship of land plants vary considerably and no phylogenetic tree with significant statistical support has been obtained. Here, we report phylogenetic analyses using 51 genes from the entire chloroplast genome sequences of 20 representative green plant species. The analyses, using translated amino acid sequences, indicated that extant bryophytes (mosses, liverworts, and hornworts) form a monophyletic group with high statistical confidence and that extant bryophytes are likely sisters to extant vascular plants, although the support for monophyletic vascular plants was not strong. Analyses at the nucleotide level could not resolve the basal relationship with statistical confidence. Bryophyte monophyly inferred using amino acid sequences has a good statistical foundation and is not rejected statistically by other data sets. We propose bryophyte monophyly as the currently best hypothesis.