Small differences in the DNA sequence contribute to the hereditary variations within a species, but also chemical modifications of the DNA, so-called epigenetic changes. In order to better understand their importance for the evolution of plants, an international research team led by Professor Oliver Bossdorf from the Institute for Evolution and Ecology at the University of Tübingen has now examined numerous populations of field Hellerkraut in a Europe-wide study. The researchers linked DNA sequences and environmental data from the places of origin with the epigenetic variation of this wild plant. According to their results, a large part of the epigenetic markings is mainly determined by the DNA sequence. However, part of the epigenetic variation is strongly related to the climatic conditions of the plants’ places of origin. Field pennyroyal could become more important in agriculture in the future as a winter cover crop and as a basis for biofuel. The study was published in the journalPLoS Genetics published.
The field pennywort or field pennywort, Latin Thlaspi arvense , is an annual white-flowering wild plant from the cruciferous family that is native to large parts of Europe and Asia. It got its German name because of the shape of its round fruits, which are reminiscent of coins. For the study, the researchers collected seeds from 207 wild populations of field pennyroyal across Europe and reared their offspring in the laboratory under standard conditions. From samples of these plants, they then analyzed their complete DNA sequences, as well as the ‘methlyome’, the entirety of DNA methylation – important epigenetic changes that influence whether and how often certain genes are transcribed.
Potential crop
“One can only understand the importance of epigenetics for the evolution and adaptability of plants if one has extensive and high-resolution data on both the genetics and epigenetics of many plant origins and their environmental conditions. So far, such data has only been available for a few model plants in plant research, such as the thale cress Arabidopsis thaliana ,” says Oliver Bossdorf. Together with the research team, he has now carried out such a combination study on a wild plant that was collected from numerous natural sites for the first time.
“We found a strong geographical variation in the DNA methylation, i.e. epigenetic markings, in the genome of field pentaphyllum. A large part of this is directly related to the DNA sequence. However, depending on the context in the genome, an important part is also determined by the environmental conditions at the plant’s place of origin,” says Bossdorf. This suggests that epigenetic variations in field pennycress could play a role in short-term adaptation to the prevailing climate. The field Hellerkraut is currently being cultivated as the basis for a new biofuel and should in future also be used as a cover crop in fields in winter, reports the scientist. “Our results could therefore also be useful for agriculture.
