Abstract Detail

Systematics Section

Hernandez Leon, Sergio [1], Pérez de la Rosa, Jorge A. [2], Jardón Barbolla, Lev O. [3], Gernandt, David S. [4].

A chloroplast DNA phylogeny of the North American hard pines (Pinus section Trifoliae).

Pinus section Trifoliae (Pinaceae) includes approximately 50 ecologically and economically important species widely distributed throughout the New World from Canada to Nicaragua and the Caribbean. Previous molecular phylogenetic studies of nuclear and chloroplast DNA recover three well supported clades, corresponding to subsections, Contortae, Australes, and Ponderosae. A phylogenetic analysis of the group was performed with highly variable chloroplast DNA sequences from two intergenic spacers, trnH-psbA and trnD-trnY-trnE, and partial sequences of the coding region, ycf1. An average of three individuals per species were sequenced, resulting in a total of 167 individuals including the outgroup, P. thunbergii. Difficulties were encountered in generating bidirectional reads for the trnH-psbA spacer in representatives for subsection Contortae but all other sequencing was straightforward. The combined matrix had an aligned length of ca. 4,100 bp and slightly more than 200 parsimony informative positions (with indels treated as missing data). The coding region ycf1 had a higher proportion of variable (including informative) sites than the spacers (12% versus 4-5%), consistent with previous reported positive selection acting on ycf1. Each of the three subsections was recovered as monophyletic, with subsection Contortae sister to subsections Australes and Ponderosae. Pinus subsection Ponderosae, with approximately 17 species, had half as many phylogenetically informative sites as subsection Australes, with approximately 29 species. In subsection Ponderosae, most sequences exhibited species non-monophyly or were unresolved but in subsections Australes and Contortae most were monophyletic (but sometimes paraphyletic) by species. In subsection Australes, the often recognized group "Oocarpae", centered in Mesoamerica, was not recovered as monophyletic with respect to the Caribbean and eastern North American species.

Broader Impacts:

1 - Instituto de Biología, Universidad Nacional Autonoma de Mexico, Departamento de Botánica, A. p. 70-367, Mexico, D.F., 04510, Mexico
2 - Universidad de Guadalajara, Instituto de Botánica, Ap 139, Zapopan, Jalisco, 45110, México
3 - Instituto de Ecología, Universidad Nacional Autónoma de México, Ecología Evolutiva, A.p. 70-275, México, D.F., 04510, México
4 - Instituto de Biología, Universidad Nacional Autónoma de México, Botánica, A.p. 70-233, México, D.F., 04510, México

Keywords:
cpDNA
phylogeny
Pinus
ycf1.

Presentation Type: Poster:Posters for Sections
Session: P
Location: Hall A/Convention Center
Date: Monday, August 2nd, 2010
Time: 5:30 PM
Number: PSY047
Abstract ID:755