SSR-based identification of genetic groups within European populations of Tuber aestivum Vittad
Tuber species are ectomycorrhizal ascomycetes establishing relationships with different host trees and forming hypogeous fruiting bodies known as truffles. Among Tuber species, Tuber aestivum Vittad. has a wide distributional range being found naturally all over Europe. Here, we performed large-scale population genetic analyses in T. aestivum to (i) investigate its genetic diversity at the European scale, (ii) characterize its genetic structure and test for the presence of ecotypes and (iii) shed light into its demographic history. To reach these goals, 230 ascocarps from different populations were genotyped using 15 polymorphic simple sequence repeat markers. We identified 181 multilocus genotypes and four genetic groups which did not show a clear geographical separation; although, one of them was present exclusively in Southeast France, Italy and Spain. Fixation index values between pairs of genetic groups were generally high and ranged from 0.29 to 0.45. A significant deficit of heterozygosity indicated a population expansion instead of a recent population bottleneck, suggesting that T. aestivum is not endangered in Europe, not even in Mediterranean regions. Our study based on a large-scale population genetic analysis suggests that genetically distinct populations and likely ecotypes within T. aestivum are present. In turn, this study paves the way to future investigations aimed at addressing the biological and/or ecological factors that have concurred in shaping the population genetic structure of this species. Present results should also have implications for the truffle market since defining genetic markers are now possible at least for some specific T. aestivum genetic groups.
KeywordsTuber aestivum Microsatellites markers Europe Population genetics
The work presented was supported by the ‘Conseil Régional de Bourgogne (Programme Jeune Chercheur Entrepreneur; Grant 20100112095254682–1)’, the ‘Ernst Göhner Stiftung’ and the Swiss State Secretariat for Education, Research and Innovation (SERI; COST Action FP1203). The UMR1136 is supported by a grant overseen by the French National Research Agency (ANR) as part of the ‘Investissements d'Avenir’ programme (ANR-11-LABX-0002-01, Lab of Excellence ARBRE). The authors thank Denise Stalder, Gérard Chevalier, Henri Frochot, Jean-Claude Ferrand, Mr. Déquéant, Mr. Besson, Willy Tegel and all other truffle growers for providing samples. We are grateful to Falbien Halkett for the help in the population genetic analysis, the choice of the tests and their interpretation. We thank Marie-Lara Bouffaud, François Le Tacon, Francis Martin and Stéphane De Mita for providing constructive advice and helpful discussions. We would like to thank Andrea Rubini, Claudia Riccioni and two anonymous reviewers for helpful comments on the manuscript and Aimée Orsini for English language editing. The authors also thank the strategic plateform ‘GENTYANE’ INRA, Ibisa 2009 and its group leader Mr. Poncet.
V.M., C.M. and D.W. designed the experiment. V.M. and C.M. performed experiment and data analyses. B.M. and H.D.V. provided assistance with DNA extraction, SSR amplification and analysis. V.M. and C.M. wrote the manuscript. M.P., A.G., S.E., B.B., F.P. and D.W. contributed to the writing and provided samples. All co-authors approved the final manuscript.
Conflict of interest
The authors declare that they have no competing interest.
- Callot G (1999) La Truffe, La Terre, la Vie. INRA, Paris, 210p Google Scholar
- Ceruti A, Fontana A, Nosenzo C (2003) Le specie Europee del genere Tuber, una revisione storica. Museo Regionale di Scienze Naturali, Monographie XXXVII, Regione Piemonte, TorinoGoogle Scholar
- Chatin A (1887) Une nouvelle espèce de truffe. C R Acad Sci 104:1132–1135Google Scholar
- Chevalier G, Frochot H (2002) La truffe de Bourgogne. Editions Pétrarque, Levallois-Perret, FranceGoogle Scholar
- Chevalier G, Desmas C, Frochot H, Riousset L (1979) L’ espèce Tuber aestivum Vitt. : I. Définition. Mushroom Science X, (Part 1):957–975Google Scholar
- Dupré C, Chevalier G, Branlard G (1985) Caractérisation des Tuber par électrophorèse de leurs protéines. In CR 1er Colloque national sur les technologies de purification des protéines. DPIC-INPL, Paris, pp 465–467Google Scholar
- IPCC (2013) Fifth Assessment Report Climate Change 2013: The Physical Science Basis—Summary for Policymakers, Working Group I Contribution to the IPCC, 2013Google Scholar
- Jourand P, Ducousso M, Reid R, Majorel C, Richert C, Riss J, Lebrun M (2010) Nickel-tolerant ectomycorrhizal Pisolithus albus ultramafic ecotype isolated from nickel mines in New Caledonia strongly enhance growth of a host plant at toxic nickel concentrations. Tree Physiol 30:1311–1319CrossRefPubMedGoogle Scholar
- Le Tacon F (2011) Point de vue sur Tuber aestivum Vittad. Le Trufficulteur 74:13–17Google Scholar
- Le Tacon F, Marçais B, Courvoisier M, Murat C, Becker M (2014) Climatic variations explain annual fluctuations in French Périgord black truffle wholesale markets but does not explain the decrease in black truffle production over the last 48 years. Mycorrhiza 24(1 supplement):115–125CrossRefGoogle Scholar
- Luikart G, Cornuet JM (1998) Empirical evaluation of a test for identifying recently bottlenecked populations from allele frequency data. Conserv Biol 12:228–237Google Scholar
- Molinier V, Murat C, Morin E, Gollotte A, Wipf D, Martin F (2013a) First identification of polymorphic microsatellite markers in the Burgundy truffle, Tuber aestivum (Tuberaceae). App Plant Sci 1:1200220Google Scholar
- Molinier V, Murat C, Frochot H, Wipf D, Splivallo R (2015) Fine-scale spatial genetic structure analysis of the black truffle Tuber aestivum and its link to aroma variability. Environ Microbiol. (accepted) http://onlinelibrary.wiley.com/doi/10.1111/1462-2920.12910/abstract
- Montecchi A, Sarasini M (2000) Funghi Ipogei d’Europa. AMB, Brescia ItalyGoogle Scholar
- Mouches C, Duthil P, Poitou N, Delmas J, Bove J (1981) Caractérisation des espèces truffières par analyse de leurs protéines en gels de polyacrylamide et application de ces techniques à la taxonomie des champignons. Mushroom Science 11:819–831Google Scholar
- Pacioni G, Pomponi G (1991) Genotypic patterns of some Italian populations of the Tuber aestivum-Tuber mesentericum complex. Mycotaxon 42:171–179Google Scholar
- Pacioni G, Frizzi G, Miranda M, Visca C (1993) Genetics of a Tuber aestivum population (Ascomycotina, Tubérales). Mycotaxon 47:93–100Google Scholar
- Payen T, Murat C, Bonito G (2014) Truffle phylogenomics: new insights into truffle evolution and truffle life cycle. In Francis M. Martin editor Adv Bot Res Vol. 70, Oxford: United Kingdom, 211–234Google Scholar
- Payen T, Murat C, Gigant A, Morin E, De Mita S, Martin F (2015) A survey of genome-wide single nucleotide polymorphisms through genome re-sequencing in the Périgord black truffle (Tuber melanosporum Vittad.). Mol Ecol Resources (in press)Google Scholar
- Riousset L, Riousset G, Chevalier G, Bardet MC (2001) Truffes d’Europe et de chine. INRA Editions, Paris, FranceGoogle Scholar
- Smith SE, Read DJ (2008) Mycorrhizal symbiosis. Academic, LondonGoogle Scholar
- Vittadini C (1831) Monographia tuberacearum. FranceGoogle Scholar