title: Gene flow between wheat and wild relatives: empirical evidence from Aegilops geniculata, Ae. neglecta and Ae. triuncialis.
abstract: Gene flow between domesticated species and their wild relatives is receiving growing attention. This study addressed introgression between wheat and natural populations of its wild relatives (Aegilops species). The sampling included 472 individuals, collected from 32 Mediterranean populations of three widespread Aegilops species (Aegilops geniculata, Ae. neglecta and Ae. triuncialis) and compared wheat field borders to areas isolated from agriculture. Individuals were characterized with amplified fragment length polymorphism fingerprinting, analysed through two computational approaches (i.e. Bayesian estimations of admixture and fuzzy clustering), and sequences marking wheat-specific insertions of transposable elements. With this combined approach, we detected substantial gene flow between wheat and Aegilops species. Specifically, Ae. neglecta and Ae. triuncialis showed significantly more admixed individuals close to wheat fields than in locations isolated from agriculture. In contrast, little evidence of gene flow was found in Ae. geniculata. Our results indicated that reproductive barriers have been regularly bypassed during the long history of sympatry between wheat and Aegilops.
authors.affiliation: Laboratory of Evolutionary Botany, Institute of Biology, University of Neuchâtel 11 rue Emile-Argand, 2000 Neuchâtel, Switzerland.
authors.forename: Nils
authors.initials: N
authors.lastname: Arrigo
authors.affiliation: Laboratory of Evolutionary Botany, Institute of Biology, University of Neuchâtel 11 rue Emile-Argand, 2000 Neuchâtel, Switzerland.
authors.forename: Roberto
authors.initials: R
authors.lastname: Guadagnuolo
authors.affiliation: Laboratory of Evolutionary Botany, Institute of Biology, University of Neuchâtel 11 rue Emile-Argand, 2000 Neuchâtel, Switzerland.
authors.forename: Sylvain
authors.initials: S
authors.lastname: Lappe
authors.affiliation: Laboratory of Evolutionary Botany, Institute of Biology, University of Neuchâtel 11 rue Emile-Argand, 2000 Neuchâtel, Switzerland.
authors.forename: Sophie
authors.initials: S
authors.lastname: Pasche
authors.affiliation: Laboratory of Evolutionary Botany, Institute of Biology, University of Neuchâtel 11 rue Emile-Argand, 2000 Neuchâtel, Switzerland.
authors.forename: Christian
authors.initials: C
authors.lastname: Parisod
authors.affiliation: Laboratory of Evolutionary Botany, Institute of Biology, University of Neuchâtel 11 rue Emile-Argand, 2000 Neuchâtel, Switzerland.
authors.forename: François
authors.initials: F
authors.lastname: Felber
keywords: admixture; amplified fragment length polymorphism; crop-to-wild gene flow; introgression; transposable element-based markers