The ability to adjust to varying biotic and abiotic conditions is a key feature of plants to survive in an ever changing environment. In the course of evolution plants therefore have developed numerous mechanisms to cope with environmental heterogeneity and its unpredictability. This thesis investigates two of these mechanisms and their population ecological consequences in the cleistogamous species Viola elatior. The conducted studies intended to (1) extend our knowledge on the impact of epigenetic variation in environmental adjustment and (2) to investigate the population genetic effects of persistent soil seed banks under changing selection regimes and decreasing population size.
