Translocation Experiment and SNP Genotyping of Candidate Genes in Adapted and Not Adapted Oak Individuals in Europe

For a translocation experiment of oak trees (Quercus petraea), seeds were collected from different provenances in Finland (Punkaharju), Poland (Blizyn), Germany (Solling), Switzerland (Valais) and France (Ventoux) representing a gradient from cold to warmer climatic environments. The oak seeds were planted and germinated under greenhouse conditions in Göttingen, Germany. The seedlings were marked and DNA was extracted from the leaves of each seedling. In total, 6.700 oak seedlings have been planted out again at the different provenance environments following a common design.  Observations of survival and growth have been conducted at the different plantations. The observations showed that the planted material had differential survival over the different environments. Records of trees that did not survive or survived with signs of maladaptation and records of trees that survived the translocation with normal growth have been kept. The first group of trees was considered as “not adapted trees” while the third group as “adapted trees” to the respective environments.  Equal number of adapted and not adapted trees has been genotyped at nine nuclear SSR loci to assess neutral genetic structure. The trees of both groups have been also genotyped at many different candidate genes for oak adaptation. The objective was to detect selection at particular gene loci after translocation in new environments.  The genetic structures of the two groups (surviving and dead plants) in different environments for both marker types are compared. Differences can help to identify genes which are responsible for tolerance against climatic stressors as drought or cold temperatures.