Genetic and chemical diversity of the toxic herb Jacobaea vulgaris Gaertn. (syn. Senecio jacobaea L.) in Northern Germany.

Tansy ragwort , Jacobaea vulgaris Gaertn. (syn. Senecio jacobaea L.), is a common Asteraceae in Europe and Asia and known to be an invasive pest in several regions in the world. Recently it is also spreading immensely in native regions like Northern Germany. Pyrrolizidine alkaloids (PAs), which are found in high amounts in Jacobaea vulgaris , are toxic for humans and potentially lethal for grazing animals. In this study we investigated 27 populations of tansy ragwort in Northern Germany for their PA concentration and composition using liquid chromatography coupled to high resolution mass spectrometry. Furthermore, we investigated the genetic structure of selected populations using amplified length polymorphism markers. We detected 98 different PAs in the samples and considerable differences of PA composition between populations. In contrast, PA content of populations did not differ significantly. Genetic (4%) differentiation among populations was low while average genetic diversity was high (0.35). There was no correlation between genetic and geographic distance. Neither genetic markers nor chemical composition revealed any connection to the geographic pattern. As we could not detect any pattern in genetic or chemical diversity, we suggest that the existence of this diversity is a result of a broad interaction with the environment rather than that of evolutionary constraints in the current selection process driving PA composition in J. vulgaris in certain chemotypes. Image 10316 • Our study revealed 98 different PA structures in J. vulgaris flowers originating from Northern Germany. • The content and composition of PAs in J. vulgaris plants within and between populations are diverse. • Samples are genetically diverse and little differentiated. • We conclude that J. vulgaris plants in Northern Germany form a panmictic metapopulation. [ABSTRACT FROM AUTHOR]