How much genetic flow is there among stands of oak trees?

Summary

This project used microsatellite analysis to evaluate the amount of genetic flow within and between species of oak in 13 woodland sites throughout Europe. The project partners assessed the genetic and ecological consequences of gene transfer and the impact of this process on forest management and conservation.

Key findings

• Paternity: oak offspring fathered by pollen from outside the stand ranged from 21-88% with an average of 60% across all studied stands.
• Maternity: on average about 40% of seedlings at study sites originated from mothers growing outside the stand, although this proportion varied between stands (20-66%)
• Low interspecies hybridisation between co-existing species
• Mating: some individual trees were much more successful at mating than others and made a much greater contribution to the next generation
• Certification: chloroplast DNA marker analysis could be used for certification purposes, if autochthony of the stand is to be used as a certification criterion
• Isolation: gene flow in oaks in Europe is so indicating that even remote stands are unlikely to experience genetic isolation

Our involvement

Forest Research was responsible for a study plot in the oak wood at Dalkeith in southeast Scotland. This site contains mostly Quercus robur with a minority of Quercus petraea interspersed through the wood. This site provided data on the level of interspecific hybridisation occurring in a wood in which Q. robur and Q. petraea are not equally represented.

Publications

• Final report
• Gerber, S. et al. (2014). High Rates of Gene Flow by Pollen and Seed in Oak Populations across Europe. PLoS ONE 9(1):e85130. doi:10.1371/journal.pone.0085130
• Lowe, A. et al. (2004). The utility and limitations of chloroplast DNA analysis for identifying native British oak stands and for guiding replanting strategy. Forestry 77(4):335-347
• Cottrell, J.E., Samuel, C.J.A., Sykes, R. (2004). The species and chloroplast DNA haplotype composition of oakwoods in the Forest of Dean planted between 1720 and 1993. Forestry 77(4):99-106

Funders and partners

Funded by the EU’s Fifth Framework Programme (FP5)

The project involved 13 partners from 10 European countries.

Status

Completed in December 2004.

Contact

Joan Cottrell