Plastome evolution and phylogeny of subtribe Aeridinae (Vandeae, Orchidaceae)

Young Kee Kim, Sangjin Jo, Se Hwan Cheon, Myounghai Kwak, Young Dong Kim, Ki Joong Kim

Research output: Contribution to journalArticle

Abstract

Subtribe Aeridinae (Vandeae, Epidendroideae, Orchidaceae) consists of 83 genera and 2,345 species. The present study completely decoded the plastomes and nuclear ribosomal (nr) RNA gene clusters of seven species of Aeridinae belonging to Gastrochilus, Neofinetia, Pelatantheria, and Thrixspermum and compared them with existing data to investigate their genome evolution and phylogeny. Although no large structural variations were observed among the Aeridinae plastomes, 14 small inversions (SI) were found in Orchidaceae for the first time. Therefore, the evolutionary trends and usefulness of SI as molecular identification markers were evaluated. Since all 11 ndh genes in the Aeridinae plastome were lost or pseudogenized, the evolutionary trends of ndh genes are discussed at the tribe and family levels. In the maximum likelihood tree reconstructed from 83 plastome genes, the five Orchidaceae subfamilies were shown to have diverged in the following order: Apostasioideae, Vanilloideae, Cypripedioideae, Orchioideae, Epidendroideaeae. Divergence times for major lineages were found to be more recent, 5–10 Mya, than previous studies, which only used two or three genes. Vandeae, which includes Aeridinae, formed a sister group with Cymbidieae and Epidendreae. The Vandeae, Cymbidieae, and Epidendreae lineages were inferred to have diverged at 25.31 Mya; thus, numerous speciation events within Aeridineae occurred since then. Furthermore, the present study reconstructed a phylogenetic tree from 422 nrITS sequences belonging to Aerdinae and allied taxa and uses it to discuss the phylogenetic positions and species identities of five endangered species.

Original languageEnglish
Article number106721
JournalMolecular Phylogenetics and Evolution
Volume144
DOIs
Publication statusPublished - 2020 Mar

    Fingerprint

Keywords

  • Aeridinae-Vandeae
  • Endangered species
  • Molecular clock
  • nrRNA gene repeating unit
  • Orchidaceae
  • Plastome

ASJC Scopus subject areas

  • Ecology, Evolution, Behavior and Systematics
  • Molecular Biology
  • Genetics

Cite this