BI Trees Research Articles

First insights in the phylogeny of Asian cheilanthoid ferns based on sequences of two chloroplast markers

Nucleotide sequences of the chloroplast rbcL and trnL-F regions were determined for 33 Asian species that bear on relationships of the cheilanthoid ferns. Maximum likelihood and Bayesian inference analyses were conducted on separate and combined sequence datasets to gain insights into phylogenetic relationships and generic circumscriptions of these cheilanthoids, with the following results. (1) Doryopteris ludens is always placed far from its congeners. (2) In rbcL sequence analysis, the Old World species of Paragymnopteris K.H. Shing form a strongly supported clade with Pellaea; these taxa are separated into two subclades in phylogenetic trees. (3) Except Paragymnopteris, Doryopteris, and Pellaea calomelanos, all the Asian cheilanthoid species sampled are grouped together and distantly segregated from the American taxa of Cheilanthes, indicating that Cheilanthes sensu Tryon & al. is not monophyletic. (4) The recognition of Sinopteris, Leptolepidium, Cheilosoria, and Mildella is not supported. All Asian species of these four small genera are grouped together with Aleuritopteris in the ML and BI trees.

Phylogenetic analysis of Paeonia sect. Moutan (Paeoniaceae) based on multiple DNA fragments and morphological data

Tree peony, being crowned the title King of Flowers in China, is of great medicinal, ornamental, and economic values. In the present study, the phylogeny of the wild tree peony species (section Moutan, Paeonia, Paeoniaceae), represented by twelve accessions collected from all eight species in the section, was investigated based on the DNA sequence in five DNA fragments from both nuclear (Adh1A, Adh2 and GPAT) and chloroplast (trnS-trnG and rps16-trnQ) genomes, as well as morphological characters. Both maximum parsimony (MP) and Bayesian inference of phylogeny (BI) trees were reconstructed based on the combined data of the DNA sequences and morphological data, respectively. The MP and BI trees have the similar topology, and the sect. Moutan clearly branched into two clades. One clade consists of two species, P. delavayi and P. ludlowii, corresponding to the subsect. Delavayanae, and another clade is composed of other six species. Within the second clade, the six species can be divided into three subclades consisting of P. rockii and P. decomposita, P. jishanensis and P. qiui, P. suffruticosa and P. ostii, respectively. Among the three subclades, P. jishanensis/P. qiui is most closely related to P. suffruticosa/P. ostii. These results provide up to date the clearest picture of the phylogeny of wild tree peony species in the sect. Moutan.