Research article

Genetic structure of a natural oak community in central Italy: Evidence of gene flow between three sympatric white oak species (Quercus, Fagaceae)

Gaby Antonecchia, Paola Fortini, Olivier Lepais, Sophie Gerber, Patrick Legér, Gabriella Stefania Scippa, Vincenzo Viscosi

Gaby Antonecchia
Università degli Studi del Molise, Cda Fonte Lappone IT-86070 Pesche, Italia
Paola Fortini
Università degli Studi del Molise, Cda Fonte Lappone IT-86070 Pesche, Italia
Olivier Lepais
INRA, UMR 1224 ECOBIOP, F-64310 Saint Pée sur Nivelle, France, Université Pau and Pays Adour, UMR 1224 ECOBIOP, F-64600 Anglet, France
Sophie Gerber
INRA, UMR 1202 BIOGECO, 69 route d’Arcachon, F-33612 Cestas cedex, France, Université de Bordeaux, F-33612 Cestas cedex, France
Patrick Legér
INRA, UMR 1202 BIOGECO, 69 route d’Arcachon, F-33612 Cestas cedex, France
Gabriella Stefania Scippa
Università degli Studi del Molise, Cda Fonte Lappone IT-86070 Pesche, Italia
Vincenzo Viscosi
MIUR, Department for Instruction, Institute “O. D’Uva”, IT-86090 Castelpetroso, Italy. Email:

Online First: July 20, 2015
Antonecchia, G., Fortini, P., Lepais, O., Gerber, S., Legér, P., Scippa, G., Viscosi, V. 2015. Genetic structure of a natural oak community in central Italy: Evidence of gene flow between three sympatric white oak species (Quercus, Fagaceae). Annals of Forest Research DOI:10.15287/afr.2015.415

Incomplete reproductive barriers between species, especially in sympatric areas where several species coexist, may result in hybridization and an increase in genetic diversity. Here we assessed the amount of genetic diversity in a community of three interfertile and sympatric European oaks (Quercus frainetto Ten., Q. petraea Liebl. Matt. and Q. pubescens Willd.) situated in central Italy. We used 11 microsatellite markers derived from Expressed Sequence Tag (EST-SSRs) and we implemented a Bayesian clustering analysis to assign individuals to species or hybrids. All genotyped loci were polymorphic for all the species and three genetic clusters corresponding to each species were detected. Significant differences and a higher level of gene flow were observed between the three oak species. Occurrence of hybrids varied markedly within the studied area: hybrids between Q. petraea and Q, pubescens were the most frequent, while hybrids between Q. petraea and Q. frainetto were particularly rare. Q. pubescens and Q. petraea showed the highest number of alleles compared to Q. frainetto,which was characterized by a low number of private, but highly frequent, alleles. However, Q. frainetto showed a lower genetic diversity and a stronger reproductive isolation from the other two oak species.

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