Advertisement

Conservation Genetics

, Volume 8, Issue 6, pp 1273–1285 | Cite as

Conservation unit status inferred for plants by combining interspecific crosses and AFLP

  • Florence Nicolè
  • Florence Tellier
  • Agnès Vivat
  • Irène Till-Bottraud
Original Paper

Abstract

Hybridization and introgression are common in plants and lead to morphological similarity between species and taxonomic confusion. This gene flow with closely related species can complicate efforts to determine whether an endangered taxon is evolutionarily distinctive and should be identified as a separate conservation unit. Potentilla delphinensis is a rare and threatened endemic species of the Southern French Alps. Two common related taxa (P. grandiflora and P. thuringiaca) are morphologically similar and occur in the same geographical locations. Thus, whether P. delphinensis represents a reliable conservation unit remained unclear. Our evaluation procedure based on a combination of molecular biology and interspecific crosses was used to define taxa within these plants. Plants were sampled from a total of 23 single and mixed localities for the three supposed taxa and were genotyped with 68 polymorphic Amplified Fragment Length Polymorphism (AFLP) loci. Fourty-one seedlings from interspecific crosses were obtained and genotyped. Amplified Fragment Length Polymorphism markers identified four genetically distinct units (P. delphinensis, P. grandiflora and two distinct groups of P. thuringiaca). All individuals of P. delphinensis formed a homogeneous and distinct taxon. This taxon was most probably an old allopolyploid from P. grandiflora and the related group of P. thuringiaca. Interspecific crosses gave low seed set and low germination rate. Furthermore, assignment test indicated that seedlings obtained from interspecific crosses were essentially apomictic rather than hybrids. These results suggest that a reproductive barrier exists between the different taxa. In conclusion, all results supported P. delphinensis as a true biological species and justified its conservation unit status. A surprising outcome of this work was the evidence of a potential new cryptic species. This study demonstrated the need to combine a molecular marker-based approach and pollination experiments for an accurate evaluation of plant taxa.

Keywords

AFLP Assignment test Cryptic species Interspecific crosses Plant conservation unit 

Notes

Acknowledgements

We would like to thank members of the Conservatoire Botanique National Alpin and Jean-François Lopez for sampling, Laurent Vinciguerra and Luc Garraud for their implication on this project, Christian Miquel, Ludovic Gielly and Delphine Rioux for technical support, and Robin Waples, Guy Lempérière, Aurélie Bonin, Myriam Gaudeul and an anonymous reviewer for useful comments on the manuscript . The project was funded by the region Rhône-Alpes.

Reference

  1. Acharya Goswami D, Matfield B (1975) Cytogenetic studies in the genus Potentilla L. New Phytol 75:135–146CrossRefGoogle Scholar
  2. Aldrich P, Parker G, Michler C, Romero-Severson J. (2003) Whole-tree silvic identifications and the microsatellite genetic structure of a red oak species complex in an Indiana old-growth forest. Can J For Res 33:2228–2237CrossRefGoogle Scholar
  3. Allendorf F, Leary R, Spruell P, Wenburg J (2001) The problems with hybrids: setting conservation guidelines. Trends Ecol Evol 16(11):613–622CrossRefGoogle Scholar
  4. Barton NH (2001) The role of hybridization in evolution. Mol Ecol 10:551–568PubMedCrossRefGoogle Scholar
  5. Beismann H, Barker JHA, Karp A, Speck T (1997) AFLP analysis sheds light on distribution of two Salix species and their hybrid along a natural gradient. Mol Ecol 6:989–993CrossRefGoogle Scholar
  6. Caille C (2001) La Potentille du Dauphiné (Potentilla delphinensis Gren. et Godron), approfondissement des connaissances et état de conservation. University of Metz, Metz, France, 25 ppGoogle Scholar
  7. Duchesne P, Bernatchez L (2002) AFLPOP: a computer program for simulated and real population allocation based on AFLP data. Mol Ecol Notes 3:380–383CrossRefGoogle Scholar
  8. Eriksson T, Hibbs MS, Yoder AD, Delwiche CF, Donoghue MJ (2003) The phylogeny of Rosoideae (Rosaceae) based on sequences of the internal transcribed spacers (ITS) of nuclear ribosomal DNA and the TRNL/F region of chloroplast DNA. Int J Plant Sci 164:197–211CrossRefGoogle Scholar
  9. Evanno G, Regnaut S, Goudet J (2005) Detecting the number of clusters of individuals using the software STRUCTURE: a simulation study. Mol Ecol 14(8):2611–2620PubMedCrossRefGoogle Scholar
  10. Felsenstein J (1985) Confidence limits on phylogenetics: an approach using the bootstrap. Evolution 39:783–791CrossRefGoogle Scholar
  11. Fraser D, Bernatchez L (2001) Adaptative evolutionary conservation: towards a unified concept for defining conservation units. Mol Ecol 10(12):2741–2752PubMedGoogle Scholar
  12. Gaudeul M, Till-Bottraud I, Taberlet P (2000) Genetic diversity in an endangered alpine plant, Eryngium alpinum L. (Apiaceae), inferred from AFLP markers. Mol Ecol 9:1625–1637PubMedCrossRefGoogle Scholar
  13. Grant V (1981) Plant speciation, 2nd edn. Columbia University Press, New York Google Scholar
  14. Grenier C, Godron DA (1848) Flore de France ou description des plantes qui croissent naturellement en France et en Corse – Tome1 I. Renonculacées – LVIII Ombellifères. J.B. Baillière, Paris, 766 ppGoogle Scholar
  15. Han T-H, De Jeu M, Van Eck H, Jacobsen E (2000) Genetic diversity of Chilean and Brazilian Alstroemeria species assessed by AFLP analysis. Heredity 84:564–569PubMedCrossRefGoogle Scholar
  16. Hansen KT, Elven R, Brochmann C (2000) Molecules and morphology in concert: tests of some hypotheses in arctic Potentilla (Rosaceae). Am J Bot 87:1466–1479PubMedCrossRefGoogle Scholar
  17. Holm S, Ghatnekar L (1996) Sexuality and no apomixis found in crossing experiments with diploid Potentilla argentea. Hereditas 125:77–82CrossRefGoogle Scholar
  18. Kardolus JP, Van Eck HJ, Van den Berg RG (1998) The potential of AFLPs in biosystematics: a first application in Solanum taxonomy (Solanaceae). Plant Syst Evol 210:87–103CrossRefGoogle Scholar
  19. Keller LF, Waller DM (2002) Inbreeding effects in wild populations. Trends Ecol Evol 17:230–241CrossRefGoogle Scholar
  20. Koontz JA, Soltis PS, Brunsfeld SJ (2001) Genetic diversity and tests of the hybrid origin of the endangered yellow larkspur. Conserv Biol 15:1608–1618CrossRefGoogle Scholar
  21. Lauber K, Wagner G (1998) Flora helvetica, 2nd edn. Verlag Paul haupt, BerneGoogle Scholar
  22. Levin DA, Francisco-Ortega J, Jansen RK (1996) Hybridization and the extinction of rare plant species. Conserv Biol 10:10–16CrossRefGoogle Scholar
  23. Mayr E (1982) The growth of biological thought – Diversity, evolution and inheritance. The Belknap Press of Harvard University Press, HarvardGoogle Scholar
  24. MINITAB version 12.2 (1998) Minitab Inc. http://www.minitab.comGoogle Scholar
  25. Morrell PL, Rieseberg LH (1998) Molecular tests of the proposed diploid hybrid origin of Gilia achilleifolia (Polemoniaceae). Am J Bot 85:1439–1453CrossRefGoogle Scholar
  26. Nei M, Li WH (1979) Mathematical model for studying genetic variation in terms of restriction endonucleases. Proceedings of the National Academy of Sciences of the USA, 76(10):5269–5273.Google Scholar
  27. Nylehn J, Hamre E, Nordal I (2003) Facultative apomixis and hybridization in arctic Potentilla section Niveae (Rosaceae) from Svalbard. Bot J Linn Soc 142:373–381CrossRefGoogle Scholar
  28. O′hanlon PC, Peakall R, Briese DT (1999) Amplified fragment length polymorphism (AFLP) reveals introgression in weedy Onopordum thistles: hybridization and invasion. Mol Ecol 8:1239–1246PubMedCrossRefGoogle Scholar
  29. Page, RDM (1998) TreeView 1.5.2. Computer software and documentation distributed by the author at website, http://taxonomy.zoology.gla.ac.uk/rod/rod.htmlGoogle Scholar
  30. Peakall R, Smouse PE (2001) GenAlex V5: Genetic Analysis in excel. Population genetic software for teaching and research. Australian National University, CanberraGoogle Scholar
  31. Petit RJ, Bodenes C, Ducousso A, Roussel G, Kremer A (2004) Hybridization as a mechanism of invasion in oaks. New Phytol 161:151–164CrossRefGoogle Scholar
  32. Pritchard JK, Stephens M, Donnelly PJ (2000) Inference of population structure using multilocus genotype data. Genetics 155:945–959PubMedGoogle Scholar
  33. Rajakaruna N, Baldwin BG, Chan R, Desrochers AM, Bohm BA, Whitton J (2003) Edaphic races and phylogenetic taxa in the Lasthenia californica complex (Asteraceae: Heliantheae): an hypothesis of parallel evolution. Mol Ecol 12:1675–1679PubMedCrossRefGoogle Scholar
  34. Richards AJ (2003) Apomixis in flowering plants: an overview. Philos Trans R Soc Lond B Biol Sci 358(1434):1085–1093Google Scholar
  35. Rieseberg L (2001) Chromosomal rearrangements and speciation. Trends Ecol Evol 16(7):351–358PubMedCrossRefGoogle Scholar
  36. Rieseberg L, Wood TE, Baack EJ (2006) The nature of plant species. Nature 440:524–527PubMedCrossRefGoogle Scholar
  37. Shaw AJ (2000) Molecular phylogeography and cryptic speciation in the mosses, Mielichhoferia elongata and M. mielichhoferiana (Bryaceae). Mol Ecol 9:595–608PubMedCrossRefGoogle Scholar
  38. Soltis PS, Gitzendanner MA (1999) Molecular systematics and the conservation of rare species. Conserv Biol 13:471–483CrossRefGoogle Scholar
  39. Swofford DL (2003) PAUP*: phylogenetic analysis using parsimony (*and other methods), version 4.0b10. Sinauer Associates, Sunderland, MAGoogle Scholar
  40. Vos P, Hogers R, Bleeker M, Reijans M, van de Lee T, Hornes M, Frijters A, Pot J, Peleman J, Kuiper M, Zabeau M (1995) AFLP: a new technique for DNA fingerprinting. Nucleic Acids Res 23:4407–4414PubMedCrossRefGoogle Scholar
  41. Waples RS (1991) Pacific salmon, Oncorhynchus spp., and the definition of “species” under the Endangered Species Act. Mar Fish Rev 53:11–22Google Scholar
  42. Waples R (1995) Evolutionarily significant units and the conservation of biological diversity under the Endangered Species Act. In: Nielsen J, Powers G (Eds) Evolution and the aquatic ecosystem: defining unique units in population conservation. American Fisheries Society, Bethesda, MDGoogle Scholar
  43. Whittall JB, Hellquist CB, Schneider EL, Hodges SA (2004) Cryptic species in an endangered pondweed community (Potamogeton, Potamogetonaceae) revealed by AFLP markers. Am J Bot 91:2022–2029Google Scholar

Copyright information

© Springer Science+Business Media, Inc. 2007

Authors and Affiliations

  • Florence Nicolè
    • 1
  • Florence Tellier
    • 1
  • Agnès Vivat
    • 1
  • Irène Till-Bottraud
    • 1
  1. 1.Laboratoire d’Ecologie AlpineCNRS-UMR 5553, Université Joseph FourierGrenoble cedex 09France

Personalised recommendations