Contemporary evolution and phenotypic plasticity or genetic fixation: Rates of evolution and adaptive processes in populations under novel selection regimes

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The aim of this project is to assess the importance of contemporary evolutionary processes influencing phenotypic plasticity or/and genetic fixation and to assess their importance for the adaptive capacity and persistence of plants under novel and multiple selection pressures. The extent and timing of contemporary evolution will be studied by using populations of five different plant species that are managed as ex-situ collections in botanical gardens (BG) hence forming a study system that allows a precise determination of phenotypic and genetic changes due to a consistent change in selection regime. We will compare 15 founder populations (cultivated for several generations in BGs) exposed to novel selection pressures for a defined amount of time with their original source populations in the wild. We will analyse 1) genetic diversity of BG and wild source populations by using restriction site-associated DNA tags (RAD tags) generated by high-throughput sequencing and 2) assess phenotypic diversity by comparison of life-history traits. To compare fitness parameters and limits of adaptation under changing conditions und multiple stress factors, all populations are reciprocally transplanted to all wild and garden sites and, in a common garden experiment, the same half-sib families are experimentally exposed to perturbations, i.e. to new environmental conditions. Thereby, the amount and interrelationship of local adaptation, phenotypic plasticity and genetic diversity in relation to the time since exposure to novel environmental conditions can be evaluated.