Erfassung der adaptiven genetischen Variation der Eiche im Hinblick auf den Klimawandel | Assessment of adaptive genetic variation in oaks with relation to climate change

Abstract

Climate change is projected to lead to a major reorganization of our forests. For example, higher annual mean temperatures, longer growth seasons and drier summers are predicted for many parts of central and southern Europe, and in North America. In order to understand the genetic adaptation to climate change we need a better understanding of the genetic regulation of key traits involved in tolerance of water and temperature stress. Oaks (Quercus spp.) are excellent model species to study the adaptation of forest trees to changing environments. They show a wide geographic distribution in Europe and in North America as dominant tree species in many forests growing under a wide range of climatic and edaphic conditions. With the availability of a growing amount of functional and expressional candidate genes we are now able to test the functional importance of genes by associating nucleotide variation in these genes with phenotypic variation in adaptive traits in segregating or natural populations. Studies trying to associate genetic variation with phenotypic variation in adaptive traits can be performed in full-sib families derived from controlled crosses (Quantitative Trait Loci [QTL] mapping) or in natural populations (association mapping). For several important adaptive traits QTL were mapped, the underlying genes have to be tested in natural populations. A future objective is to test whether genes that underlie phenotypic variation in adaptive traits are involved in local genetic adaptation and viability selection at the seedling stage, linked to reciprocal transplant experiments in order to assess the performance over climatic gradients.