Abstract Detail

Systematics Section/ASPT

Abiero, Sam [1], Arevalo Burbano, Rafael [2], Cameron, Kenneth [3].

Phylogenetic utility of the low-copy nuclear gene PhyC in the Neotropical orchid genus Mormolyca (Maxillariinae).

Sequences from plastid regions along with ITS nuclear ribosomal DNA, have been traditionally used by orchid systematists to reconstruct phylogenies. We demonstrate the phylogenetic utility of the low-copy nuclear gene PhyC in the Neotropical orchid genus Mormolyca. PhyC is a member of the phytochrome family of genes, which code for photoreceptive proteins in plants and regulate flowering and developmental pathways. The utility of any DNA region for phylogenetic analysis is usually determined by ease of amplification and sequencing, confidence in phylogenetic character alignment, and variability across taxon sampling. Analyses of a combination of plastid Chloroplast (matK+trnK / atpB-rbcL / rpoC1 / ycf1) and nuclear ribosomal (ITS and ETS) DNA regions for the genus Mormolyca have yield phylogenetic structure at various levels of its tree. In the search for better resolution and support at lower levels of the phylogeny, we sequenced about 650 bp of the 5 - half of PhyC exon 1 for 22 species of Mormolyca and 5 other species of Maxillariinae. We compare the phylogenetic resolution and clade support for phyC-derived trees to the plastid- and nuclear ribosomal-derived phylogenies. Results demonstrate that although PhyC required time and effort to optimize amplification, the portion examined was highly variable, alignable and phylogenetically informative at the level of species. It was more variable than any other plastid marker in percent variability and comparable to the nuclear ribosomal ITS and ETS regions. Although we only demonstrate the phylogenetic utility of PhyC in a small Neotropical genus, it is likely to be useful among other orchid taxa.

Broader Impacts:

1 - University of Wisconsin-Madison, Department of Botany, 430 Lincoln Drive , Madison, WI, 53706, USA
2 - University Of Wisconsin, Botany, 244 Birge Hall, 430 Lincoln Dr., Madison, WI, 53706, USA
3 - University Of Wisconsin, Department Of Botany, 154 Birge Hall, 450 Lincoln Drive, Madison, WI, 53706, USA

Keywords:
Orchidaceae
phylogeny
neotropics
PhyC
low copy nuclear genes.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Battelle South/Convention Center
Date: Monday, July 9th, 2012
Time: 5:30 PM
Number: PSY038
Abstract ID:1007