Important legal notice
Contact   |   Search on Europa   
SEARCH ON EU‑AGRINET  Links | Contacts | Disclaimer Printer Friendly
graphic element

Intra- and interspecific gene flow in oaks as mechanisms promoting diversity and adaptive potential

The project aims to estimate the amount of intra- and interspecific (hybridisation) gene flow in European oaks, using Quercus petraea and Quercus robur mainly, but also other Mediterranean white oaks. This will be done by using genetic fingerprints and applying parentage analysis. The project will investigate the natural gene flow from pollen and seed dispersal, and the artificial flow from non-natural seed transfer by man. The consequences of gene flow at the genetic but also at the ecological level will be addressed. Genomic regions affected by hybridisation will be identified and fitness related traits compared between hybrids and the parental species. These comparisons will be carried out on juvenile and adult material, and natural flow on management rules will be addressed by considering different real cases in strong co-operation with end-users associated with the project.

The project has three main objectives:
1) to trace and quantify gene flow and hybridisation in terms of distances and rates:
Effective natural pollen and seed movements will be detected in 12 stands, distributed throughout Europe from Scandinavia to Spain, based on parentage analysis using micro-satellite markers. Gene flow will be quantified as distances and rates of dispersal, and will be delivered in the form of dispersal curves. Past artificial seed transfer will be detected at a local or national level by analysing the distribution of cpDNA.

2) to evaluate genetic and ecological consequences of gene flow and hybridisation on the adaptation of oak stands:
Genomic modifications due to the insertion of new genomic segments will be localised on genetic linkage maps, so genomic regions that are 'sensitive' to gene flow or hybridisation will be identified. The fitness of interspecific hybrids will be compared to their parents, both in situ and ex situ (in controlled environments).

3) to evaluate impacts of gene flow on management rules and silvicultural regimes of oak stands:
Detection and evaluation of gene flow will lead to practical decisions and silviculture recommendations concerning the management of seed and conservation stands. Furthermore, computer simulation models will forecast the short and long term consequences of gene flow on the distribution of diversity in oak stands.
The end-users of the project (forest services, conservation agencies), will be closely associated in testing various implications of gene flow in management and conservation issues.

Progress to Date
Experiments were conducted to establish and improve high throughput DNA extraction protocols on different tissues of oak material (seed, cotyledons, pericarp and cambium). Statistical methods for paternity analysis were implemented in the form of a computer package called FaMoz. Thirteen Intensive Studied Plots (ISPs) were installed in different European countries, where all the trees were mapped and partially genotyped for six micro-satellite loci during the first year. Experiments were installed in situ and under controlled conditions to test the differential fitness between interspecific hybrids and the parental species.

Pollen dispersion curves were constructed based on parentage analysis between the adult and offspring cohorts (acorns and seedlings) and similar investigations were conducted for seed dispersion. Different issues were addressed: yearly variation of geneflow, spatial variation and within crown variation.

A consensus genetic map of Quercus was constructed based on all genetic markers available. QTLs for different phenotypic traits involved in adaptation and species differentiation were mapped. Several genes involved in stress response (anoxia or osmotic stress) were identified, based on differential screening analysis. Comparative analyses of hybrids versus parental species were conducted to identify sites where hybrid fitness differed from parental fitness.


Scientist responsible for the project

69 route d'Arcachon
33612 Cestas CEDEX Cedex
France - FR

Phone: +33 5 57 12 28 32
Fax: +33 5 57 12 28 81


Project ID QLRT-1999-30960
Organisation Institut National de la Recherche Agronomique
Area 5.3.1
Start date 01 January 2001
Duration (months) 48
Total cost 4 352 263 €
Total EC contribution   2 080 971 €
Status Completed
Web address of the project

The partners

  • The Danish Forest and Landscape Research Institute, Denmark - DK
  • National Institute for Agricultural Quality Control, Hungary - HU
  • Nekazal Ikerketa eta Garapenerako Euskal Erakundea-Instituto Vasco de Investigacion y Desarrollo Agrario, Spain - ES
  • Eidgenössische Forschungsanstalt für Wald, Schnee und Landschaft (Swiss Federal Institute for Forest, Snow and Landscape Research), Switzerland - CH
  • Natural Environment Research Council (NERC), United Kingdom (The) - GB

List by