Affordable Access

deepdyve-link
Publisher Website

More introgression with less gene flow: chloroplast vs. mitochondrial DNA in the Picea asperata complex in China, and comparison with other Conifers.

Authors
  • Du, Fang K
  • Petit, Rémy J
  • Liu, Jian Quan
Type
Published Article
Journal
Molecular Ecology
Publisher
Wiley (Blackwell Publishing)
Publication Date
Apr 01, 2009
Volume
18
Issue
7
Pages
1396–1407
Identifiers
DOI: 10.1111/j.1365-294X.2009.04107.x
PMID: 19284474
Source
Medline
License
Unknown

Abstract

Recent work has suggested that rates of introgression should be inversely related to levels of gene flow because introgressed populations cannot be 'rescued' by intraspecific gene flow if it is too low. Mitochondrial and chloroplast DNA (mtDNA and cpDNA) experience very different levels of gene flow in conifers due to their contrasted maternal and paternal modes of transmission, hence the prediction that mtDNA should introgress more readily than cpDNA in this group. Here, we use sequence data from both mtDNA and cpDNA to test this hypothesis in a group of closely related spruces species, the Picea asperata complex from China. Nine mitochondrial and nine chloroplast haplotypes were recovered from 459 individuals in 46 natural populations belonging to five species of the Picea asperata complex. Low variation was found in the two mtDNA introns along with a high level of differentiation among populations (G(ST) = 0.90). In contrast, we detected higher variation and lower differentiation among populations at cpDNA markers (G(ST) = 0.56), a trend shared by most conifer species studied so far. We found that cpDNA variation, although far from being fully diagnostic, is more species-specific than mtDNA variation: four groups of populations were identified using cpDNA markers, all of them related to species or groups of species, whereas for mtDNA, geographical variation prevails over species differentiation. The literature suggests that mtDNA haplotypes are often shared among related conifer species, whereas cpDNA haplotypes are more species-specific. Hence, increased intraspecific gene flow appears to decrease differentiation within species but not among species.

Report this publication

Statistics

Seen <100 times