Abstract Detail

Systematics Section

Steele, Kelly [1], Ellingbo, Aaron [1], Wojciechowski, M [2].

Phylogenetic analyses of Medicago using plastid and nuclear-encoded molecular markers: key to understanding chromosomal and morphological evolution within the genus.

Phylogenetic analyses of the genus Medicago using a five molecular marker data set of both plastid and nuclear-encoded molecular markers (plastid trnK/matK region, nuclear encoded GA3 oxidase gene, nrDNA ITS, CNGC5, and b-cop-likegene) are used to develop a robust phylogeny to consider hypotheses of chromosomal and morphological evolution within the genus. Results of Bayesian analyses of these data support the hypothesis of a sister group relationship between the section Medicago clade that includes alfalfa, M. sativa, and a subsection Pachyspireae clade that includes the modellegume, M. truncatula. A data set comprised of nrDNA ITS sequences from more than 150 samples including multiple accessions of most species was analyzed separately. Results of Bayesian analyses of those data support the hypothesis that the putative parents of two polyploid taxa, M. scutellata and M. rugosa (2n=30), both thought to be the result of hybridization of a2n=14 parent and a 2n=16 parent (the ancestral condition), are within the subsection Pachyspireae clade and may have at least one parent in common.

Broader Impacts:

1 - Arizona State University, School of Life Sciences, Tempe, AZ, 85287-4501, USA
2 - Arizona State University, PO Box 874501, Tempe, AZ, 85287-4501, USA

Keywords:
Medicago
Phylogeny
matK
ITS
chromosomal evolution.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Khorassan Ballroom/Chase Park Plaza
Date: Monday, July 11th, 2011
Time: 5:30 PM
Number: PSY016
Abstract ID:740