title: Pollen-mediated gene flow and fine-scale spatial genetic structure in Olea europaea subsp. europaea var. sylvestris.
abstract: Wild olive ( Olea europaea subsp. europaea var. sylvestris ) is important from an economic and ecological point of view. The effects of anthropogenic activities may lead to the genetic erosion of its genetic patrimony, which has high value for breeding programmes. In particular, the consequences of the introgression from cultivated stands are strongly dependent on the extent of gene flow and therefore this work aims at quantitatively describing contemporary gene flow patterns in wild olive natural populations.
  
  
  
  The studied wild population is located in an undisturbed forest, in southern Spain, considered one of the few extant hotspots of true oleaster diversity. A total of 225 potential father trees and seeds issued from five mother trees were genotyped by eight microsatellite markers. Levels of contemporary pollen flow, in terms of both pollen immigration rates and within-population dynamics, were measured through paternity analyses. Moreover, the extent of fine-scale spatial genetic structure (SGS) was studied to assess the relative importance of seed and pollen dispersal in shaping the spatial distribution of genetic variation.
  
  
  
  The results showed that the population under study is characterized by a high genetic diversity, a relatively high pollen immigration rate (0·57), an average within-population pollen dispersal of about 107 m and weak but significant SGS up to 40 m. The population is a mosaic of several intermingled genetic clusters that is likely to be generated by spatially restricted seed dispersal. Moreover, wild oleasters were found to be self-incompatible and preferential mating between some genotypes was revealed.
  
  
  
  Knowledge of the within-population genetic structure and gene flow dynamics will lead to identifying possible strategies aimed at limiting the effect of anthropogenic activities and improving breeding programmes for the conservation of olive tree forest genetic resources.
authors.affiliation: Department of Food Science, Parco Area delle Scienze, 95/a, 43124 Parma, Italy.|Institute of Tree and Timber (IVALSA), Italian National Research Council (CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy.
authors.forename: D
authors.initials: D
authors.lastname: Beghè
authors.affiliation: Institute of Biosciences and BioResources (IBBR), Italian National Research Council (CNR), Via Madonna del Piano 10, 50019 Sesto Fiorentino (FI), Italy.
authors.forename: A
authors.initials: A
authors.lastname: Piotti
authors.affiliation: University of Zagreb, Faculty of Agriculture, Zagreb, Croatia.
authors.forename: Z
authors.initials: Z
authors.lastname: Satovic
authors.affiliation: Andalusian Institute of Agricultural Research and Training (IFAPA), Centro 'Alameda del Obispo', Avda. Menéndez Pidal s/n, 14004 Córdoba, Spain.
authors.forename: R
authors.initials: R
authors.lastname: de la Rosa
authors.affiliation: Andalusian Institute of Agricultural Research and Training (IFAPA), Centro 'Alameda del Obispo', Avda. Menéndez Pidal s/n, 14004 Córdoba, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Belaj
mesh_terms: D051456:Gene Flow / Q000235:genetics*; D014644:Genetic Variation / Q000235:genetics; D005828:Genetics, Population; D031658:Olea / Q000235:genetics*; D011058:Pollen / Q000235:genetics*; D013030:Spain
keywords: Olea europaea; SGS; SSRs; conservation genetics; gene flow; oleaster; paternity assignment; pollen dispersal; seed dispersal; wild olive