Integration of Different Approaches to Explore Genetic and Adaptive Variation of Castanea sativa Mill.: Perspectives for Gene Conservation

An overview of recent studies on genetic diversity and adaptive response of European chestnut (Castanea sativa Mill.) in relation to major evolutionary factors and anthropogenic impacts is reported. This, in order to predict the future dynamics of this ecosystem and to develop strategies for conservation and sustainable management in the frame of environmental changes (climate and social). We summarized the results of populations genetics studies conducted on the whole distribution range of the species, highlighting the importance to integrate the genetic results with environmental data by GIS support. The results indicated three main gene pools from East to West according to the hypothesized glacial refugia. Common garden trials and ex situ germplasm collections were used to study the variation and phenotypic plasticity of adaptive traits in selected geographic provenances from Turkey, Spain, Greece and Italy. Results related to phenology, growth and drought tolerance are summarized and discussed in relation to environment variation of the original sites. We also reported the results of mapping studies conducted on full sib families from controlled crosses. Genetic linkage maps were constructed and QTL analysis revealed genome regions involved in the control of bud burst, bud set and water use efficiency. These results are discussed in view of future research and applied perspectives.