Abstract Detail

Systematics

Gernandt, David [1], Liston, Aaron [2].

Multilocus nuclear phylogenetics of the main lineages of Pinus and other pinoid Pinaceae.

Improvements in DNA sequencing and analytical approaches are prompting the reexamination of phylogenetic relationships in even the best studied taxonomic groups. Early phylogenetic studies of Pinus and related genera were based on morphology and a diversity of molecular markers, including immunology, restriction sites, nuclear ribosomal DNA sequences, plastid DNA, mitochondrial DNA, and single-copy nuclear genes. The results of these studies agreed in the monophyly of Pinus and its division into two subgenera, each with subclades that vary in their degree of morphological cohesiveness. However, past emphasis on plastid DNA sequences may have biased our understanding of pine relationships. We present HybSeq results for 876 nuclear loci from 21 representative taxa, including 15 from the major lineages of Pinus, one from each of the other four genera of pinoid Pinaceae (Cathaya, Picea, Larix, and Pseudotsuga), and two outgroups (Abies and Tsuga). We focus on two points of discordance between plastid and nuclear DNA: the interrelationships of Cathaya, Picea, and Pinus and the interrelationships of the North American hard pines (section Trifoliae). Our objectives are to determine whether incomplete lineage sorting, reticulation, unintentional inclusion of paralogs, or estimation errors best account for discordance between nuclear and plastid estimates of phylogeny.

1 - Universidad Nacional Autonoma de Mexico, Botanica, Apartado Postal 70-233, Coyoacan, Ciudad de Mexico, CDMX, 04510, Mexico
2 - Oregon State University, Department Of Botany & Plant Pathology, 2082 Cordley Hall, Corvallis, OR, 97331, United States

Keywords:
Pine
low copy nuclear gene
HybSeq
Incomplete lineage sorting
paralogy.

Presentation Type: Oral Paper
Session: SYS5, Systematics V: Gymnosperms to Monocots part A
Location: Virtual/Virtual
Date: Friday, July 31st, 2020
Time: 12:30 PM
Number: SYS5001
Abstract ID:478
Candidate for Awards:None