Thünen Research Prize 2021

The award ceremony for the Thünen Research Prize 2021 took place at the main campus of the Thünen Institute in Braunschweig at the end of September 2022. The prize was awarded to Dr. Niels Müller, PD Dr. Birgit Kersten and PD Dr. Matthias Fladung, from the Genome Research group of the Thünen Insitute of Forest Genetics, for an outstanding scientific achievement. Together with co-authors from Sweden, Italy and Canada, they published a groundbreaking paper in the journal Nature Plants describing the genetic and molecular basis of sex determination in poplars.

The work is based on research that was pursued at the institute for more than 20 years. This work resulted in the genetic mapping of the sex trait and the development of molecular gene markers for early identification of sex in quaking aspen. Financial support was granted by the German Research Foundation (DFG) and the Ministry of Education and Research (BMBF). The results now published in Nature Plants show that despite the diversity of genomic architectures of sex determination in different poplar species, sex determination is based on the same mechanism, the activity of the single gene ARR17. If this gene is present and active, female floral organs (carpels) develop; if the gene is absent or switched off, male floral organs (stamens) develop. Experimentally, the authors demonstrated the function of ARR17 as a sex switch using CRISPR/Cas9 gene editing.

The results contribute to our understanding of plant biology in general and the evolution of sex determination in the Salicaceae family in particular. Furthermore, they are valuable for practical applications such as poplar breeding and conservation.

Original publication: Müller, N.A., Kersten, B. et al. A single gene underlies the dynamic evolution of poplar sex determination. Nat. Plants 6, 630–637 (2020). doi.org/10.1038/s41477-020-0672-9.