Differences in content of secondary metabolites as a factor explaining success of invasive species

A lot of plant species got into new environment and there they became invasive species by the influence of the anthropogenic activity. There are many hypotheses which deal with explanation of success of the plant invasive species. One of these hypotheses is called EICA. This says that the plants in the invasive range do not meet their natural enemies, and therefore they create less secondary metabolites than plants in the native range. The non-native plants can invest their spare energy into biomass. This thesis is built on a garden experiment done by Inés Abela Hofbauer from 2007 to 2010. The plants (Cirsium arvense) used in that experiment were used for investigation of differences in volume of chosen phenolic acids and flavonoids in invasive and native species. The plants were grown from seeds from a native range in Europe (Czech Republic and Spain) and an invasive range in North America (Illinois and Nebraska) in an experimental garden in the Czech Republic. During the growing period the plants were protected from the herbivores. Methanol extracts were made of the leaves of these grown plants. I analysed them with HPLC method (high-performance liquid chromatography). I have detected 11 phenolic acids and 3 flavonoids in the samples. The same phenolics occurred in plants from both native and invasive..