title: The eastern part of the Fertile Crescent concealed an unexpected route of olive (Olea europaea L.) differentiation.
abstract: Olive is considered a native plant of the eastern side of the Mediterranean basin, from where it should have spread westward along the Mediterranean shores, while little is known about its diffusion in the eastern direction.
  
  
  
  Genetic diversity levels and population genetic structure of a wide set of olive ecotypes and varieties collected from several provinces of Iran, representing a high percentage of the entire olive resources present in the area, was screened with 49 chloroplast and ten nuclear simple sequence repeat markers, and coupled with archaeo-botanical and historical data on Mediterranean olive varieties. Approximate Bayesian Computation was applied to define the demographic history of olives including Iranian germplasm, and species distribution modelling was performed to understand the impact of the Late Quaternary on olive distribution.
  
  
  
  The results of the present study demonstrated that: (1) the climatic conditions of the last glacial maximum had an important role on the actual olive distribution, (2) all Iranian olive samples had the same maternal inheritance as Mediterranean cultivars, and (3) the nuclear gene flow from the Mediterranean basin to the Iranian plateau was almost absent, as well as the contribution of subspecies cuspidata to the diversity of Iranian olives.
  
  
  
  Based on this evidence, a new scenario for the origin and distribution of this important fruit crop has been traced. The evaluation of olive trees growing in the eastern part of the Levant highlighted a new perspective on the spread and distribution of olive, suggesting two routes of olive differentiation, one westward, spreading along the Mediterranean basin, and another moving towards the east and reaching the Iranian plateau before its domestication.
authors.affiliation: CNR - Institute for Agricultural and Forest Systems in the Mediterranean, via Madonna Alta, 128, 06128 Perugia, Italy.|Tarbiat Modares University, Department of Horticultural Science, Jalal Ale Ahmad Highway, PO Box 14115111, Tehran, Iran.|National Institute of Genetic Engineering and Biotechnology (NIGEB), Shahrak-e Pajoohesh, Km 15, Tehran - Karaj Highway, PO Box 14965161, Tehran, Iran.
authors.forename: Soraya
authors.initials: S
authors.lastname: Mousavi
authors.affiliation: CNR - Institute of Biosciences and Bioresources, via Madonna Alta, 130, 06128 Perugia, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Mariotti
authors.affiliation: CNR - Institute of Biosciences and Bioresources, Via Madonna del Piano, 10, 50019 Sesto Fiorentino, Florence, Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Bagnoli
authors.affiliation: ISMEO - International Association of Mediterranean and Oriental Studies, Corso Vittorio Emanuele II, 244, 00186 Rome, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Costantini
authors.affiliation: CNR - Institute of Biosciences and Bioresources, via Madonna Alta, 130, 06128 Perugia, Italy.
authors.forename: Nicolò G M
authors.initials: NGM
authors.lastname: Cultrera
authors.affiliation: Tarbiat Modares University, Department of Horticultural Science, Jalal Ale Ahmad Highway, PO Box 14115111, Tehran, Iran.
authors.forename: Kazem
authors.initials: K
authors.lastname: Arzani
authors.affiliation: CNR - Institute of Biosciences and Bioresources, via Madonna Alta, 130, 06128 Perugia, Italy.
authors.forename: Saverio
authors.initials: S
authors.lastname: Pandolfi
authors.affiliation: CNR - Institute of Biosciences and Bioresources, Via Madonna del Piano, 10, 50019 Sesto Fiorentino, Florence, Italy.
authors.forename: Giovanni Giuseppe
authors.initials: GG
authors.lastname: Vendramin
authors.affiliation: National Institute of Genetic Engineering and Biotechnology (NIGEB), Shahrak-e Pajoohesh, Km 15, Tehran - Karaj Highway, PO Box 14965161, Tehran, Iran.
authors.forename: Bahareh
authors.initials: B
authors.lastname: Torkzaban
authors.affiliation: National Institute of Genetic Engineering and Biotechnology (NIGEB), Shahrak-e Pajoohesh, Km 15, Tehran - Karaj Highway, PO Box 14965161, Tehran, Iran.
authors.forename: Mehdi
authors.initials: M
authors.lastname: Hosseini-Mazinani
authors.affiliation: CNR - Institute of Biosciences and Bioresources, via Madonna Alta, 130, 06128 Perugia, Italy.
authors.forename: Luciana
authors.initials: L
authors.lastname: Baldoni
mesh_terms: D001499:Bayes Theorem; D018742:DNA, Chloroplast / Q000235:genetics; D051456:Gene Flow; D014644:Genetic Variation; D040582:Inheritance Patterns; D007492:Iran; D018895:Microsatellite Repeats; D031658:Olea / Q000235:genetics*
chemical_list: D018742:DNA, Chloroplast
keywords: Olea europaea subsp. europaea var. europaea; SSR markers; centre of origin; chloroplast markers; ecotypes; genetic differentiation; population genetics