An overview of the phylogenetic relationships within Epidendroideae inferred from multiple DNA regions and recircumscription of Epidendreae and Arethuseae (Orchidaceae)

Abstract

Phylogenetic relationships within the epidendroid orchids with emphasis on tribes Epidendreae and Arethuseae were assessed with parsimony and model-based analyses of individual and combined DNA sequence data from ITS nuclear ribosomal DNA and plastid trnL intron, the trnL-F spacer, matK (gene and spacers), and rbcL regions. Despite the absence of boostrap support for some of the relationships, a well-resolved and supported consensus was found, for which most clades were present in more than one individual analysis. Most clades of this consensus attained high posterior probabilities with a Bayesian approach. Circumscription of Arethuseae and Epidendreae are different from most orchid systems based on morphology, but they correspond to a combination of patterns from several less comprehensive orchid phylogenetic analyses previously published. A new circumscription of Epidendreae includes only Neotropical subtribes (Bletiinae, Chysiinae, Laeliinae, Ponerinae, and Pleurothallidinae), whereas Arethuseae include Coelogyninae (all Old World) and Arethusinae (pantropical). Many previously included genera will need to be moved to other tribes. Taxa previously assigned to be Old World Epidendreae are related to different groups of Old World orchids, and this study can serve as a guide for sampling strategies in future studies to resolve troublesome epidendroid orchid clades.

Diversidade de fungos micorrízicos Epulorhiza spp. isolados de Epidendrum secundum (Orchidaceae)

“…está compreendida na subfamília Epidendroideae, tribo Epidendreae, subtribo Laellinae (van den Berg et al, 2000Berg et al, , 2005. É uma espécie de orquídea de hábito terrestre e, ou, rupícola, comum em campos graminóides e em afloramentos rochosos dos campos de altitude da Serra das Cabeças, que está localizada no Parque Estadual da Serra do Brigadeiro (PESB), MG (Caiafa & Silva, 2005).…”

A Comparison and Combination of Plastid atpB and rbcL Gene Sequences for Inferring Phylogenetic Relationships within Orchidaceae

“…(1999) to include 158 ingroup and 13 outgroup taxa. Since that study contains the greatest genus and species level sampling to date, it has remained a standard to which most subsequent molecular phylogenetic studies of orchids have been compared (e.g., van den Berg et al 2005). A handful of additional phylogenetic studies focused on the entire Orchidaceae have been published using genes other than rbcL (e.g., ndhF by Neyland andUrbatsch 1995, 1996; 18S by Cameron and Chase 2000; matK by Freudenstein et al 2004), but only the mitochondrial nadl b-e intron published by Freudenstein et a!.…”

Molecular phylogenetics of subtribe Aeridinae (Orchidaceae): insights from plastid matK and nuclear ribosomal ITS sequences

“…A few molecular phylogenetic analyses have been conducted in subtribe Aeridinae: Jarrell and Clegg (1995) for internal transcribed spacers (ITS) and the maturase-coding gene (matK); Cameron et al (1999) for the large subunit of ribulose bisphosphate carboxilase-coding gene (rbcL); and van den Berg et al (2005) for ITS, matK, rbcL, and the transfer RNA gene for leusine and phenylalanine (trnL-F). However, neither study produced satisfactory conclusions of phylogenetic relationships within subtribe Aeridinae because Jarrell and Clegg (1995) sampled only 17 genera from the subtribe, Cameron et al (1999) sampled only three genera in their global phylogenetic analysis in Orchidaceae, and van den Berg et al (2005) used only a single genus. A more comprehensive molecular analysis of the subtribe is required because extensive sampling of taxa is key to increase overall phylogenetic accuracy (Zwick and Hillis 2002).…”