Comparison of genetic diversity estimates within and among populations of maritime pine using chloroplast simple-sequence repeat and amplified fragment length polymorphism data

Authors

  • M. M. Ribeiro,

    Corresponding author
    1. Unidade Departamental de Silvicultura e Recursos Naturais, Escola Superior Agrária, 6001-909 Castelo Branco, Portugal,
      M. M. Ribeiro. Tel. 351 272 339970; Fax: 351 272 339901; E-mail: mribeiro@esa.ipcb.pt
    Search for more papers by this author
    • M. M. Ribeiro and S. Mariette contributed equally to this work.

  • S. Mariette,

    1. CEMAGREF, Nogent-sur-Vernisson, France,
    2. INRA, Laboratoire de Génétique et Amélioration des Arbres Forestiers, Cestas, France,
    Search for more papers by this author
    • M. M. Ribeiro and S. Mariette contributed equally to this work.

  • G. G. Vendramin,

    1. Istituto Miglioramento Genetico Piante Forestali, Firenze, Italy,
    Search for more papers by this author
  • A. E. Szmidt,

    1. Laboratory of Molecular Population Genetics, Kyushu University, Fukuoka, Japan
    Search for more papers by this author
  • C. Plomion,

    1. INRA, Laboratoire de Génétique et Amélioration des Arbres Forestiers, Cestas, France,
    Search for more papers by this author
  • A. Kremer

    1. INRA, Laboratoire de Génétique et Amélioration des Arbres Forestiers, Cestas, France,
    Search for more papers by this author

  • This study is part of MM Ribeiro’s PhD thesis about the genetic structure of Pinus pinaster by using nuclear and cytoplasmic markers. S Mariette compared different molecular markers to assess genetic diversity of different tree species. AE Szmidt is working with the application of molecular approaches to the study of plant evolutionary biology. GG Vendramin is involved in microsatellite marker analysis of many forest tree species. C Plomion is interested in the application of QTL analysis and mapping to operational tree breeding programme. A Kremer’s research is focused on the organization and dynamics of gene diversity in forest trees.

M. M. Ribeiro. Tel. 351 272 339970; Fax: 351 272 339901; E-mail: mribeiro@esa.ipcb.pt

Abstract

We compared the genetic variation of Pinus pinaster populations using amplified fragment length polymorphism (AFLP) and chloroplast simple-sequence repeat (cpSSR) loci. Populations’ levels of diversity within groups were found to be similar with AFLPs, but not with cpSSRs. The high interlocus variance associated with the AFLP loci could account for the lack of differences in the former. Although AFLPs revealed much lower genetic diversity than cpSSRs, the levels of among-population differentiation found with the two types of marker were similar, provided that loci showing fewer than four null-homozygotes, in any population, were pruned from the AFLP data. Moreover, the French and Portuguese populations were clearly differentiated from each other, with both markers. The Mantel test showed that the genetic distance matrix calculated using the AFLP data was correlated with the matrix derived from the cpSSRs. Because of the concordance found between markers we conclude that gene flow was indeed the predominant force shaping nuclear and chloroplastic genetic variation of the populations within regions, at the geographical scale studied.

Ancillary