National Research Council of Italy

Institute of Biosciences and BioResources

DISBA logo CNR logo
IBBR publication #1727

Pollen-mediated gene flow and fine-scale spatial genetic structure in Olea europaea subsp. europaea var. sylvestris

Beghè D, Piotti A, Satovic Z, de la Rosa R, Belaj A

Annals of Botany 119 (4): 671-679. (2017)
doi: 10.1093/aob/mcw246

Background and Aims Wild olive (Olea europaea subsp. europaea var. sylvestris) is important from an eco- nomic 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 introgres- sion from cultivated stands are strongly dependent on the extent of gene flow and therefore this work aims at quanti- tatively describing contemporary gene flow patterns in wild olive natural populations. o Methods 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 disper- sal in shaping the spatial distribution of genetic variation. o Key Results The results showed that the population under study is characterized by a high genetic diversity, a relatively high pollen immigration rate (0o57), 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. o Conclusions Knowledge of the within-population genetic structure and gene flow dynamics will lead to identify- ing possible strategies aimed at limiting the effect of anthropogenic activities and improving breeding programmes for the conservation of olive tree forest genetic resources.

IBBR Authors:
Actions
Select by Year
Select by Type
Select by Author
*
*
*
*
Istituto di Bioscienze e Biorisorse (IBBR/CNR)
Via G. Amendola 165/A, I-70126 Bari (Italy)
Copyright © 2012-2024. All Rights Reserved.