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Updated: Jun 1, 2026
07:01
Processing the Loblolly Pine PtGen2 cDNA Microarray
Published on: March 20, 2009
Evolutionary relationships among Pinus (Pinaceae) subsections inferred from multiple low-copy nuclear loci
John Syring1, Ann Willyard, Richard Cronn
1Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon 97331 USA;
American Journal of Botany
|June 8, 2011
Summary
Phylogenetic analysis of pine (Pinus) species using nuclear genes provides a robust evolutionary tree. This study resolves deep divergences and clarifies the placement of key species, improving pine systematics.
Area of Science:
- Botany
- Evolutionary Biology
- Genetics
Background:
- Phylogenetic relationships among Pinus species remain incompletely resolved using traditional DNA markers like nrITS and cpDNA.
- Previous studies have faced challenges in fully elucidating the evolutionary history of pines.
Purpose of the Study:
- To resolve phylogenetic relationships among Pinus species using low-copy nuclear genes.
- To establish a well-supported sectional topology for the genus Pinus.
- To clarify the systematic positions of Pinus nelsonii, Pinus krempfii, and Pinus contorta.
Main Methods:
- Sequencing of four low-copy nuclear genes from 12 Pinus species representing all subsections.
- Development of nuclear markers from screening 73 mapped conifer anchor loci.
- Phylogenetic analysis using combined data from low-copy nuclear loci.
Main Results:
- Combined analysis of low-copy nuclear loci yielded a well-supported sectional topology, congruent with deep divergence hypotheses in Pinus.
- Results strongly support the placement of P. nelsonii and P. krempfii within specific sections.
- The placement of P. contorta remained ambiguous based on the analyzed loci.
Conclusions:
- Low-copy nuclear genes are crucial for resolving complex phylogenetic relationships in Pinus.
- A successful phylogenetic strategy requires numerous low-copy nuclear loci from independent linkage groups.
- The presented locus screening strategy can aid in developing new phylogenetic markers for Pinus and other conifers.
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