Fruit evolution and adaptation to Mediterranean habitats in Raphanus (Brassicaceae)

Dr Tina Steinbrecher and Prof Gerhard Leubner (Royal Holloway University of London) are associated collaboration partners in a DFG Trilateral Project (Germany, Israel, Palestine) led by Prof. Klaus Mummenhoff at the University of Osnabrück (Germany). The project is an interdisciplinary approach to investigate the adaptive value of the divergence in fruit and diaspore architecture in the genus Raphanus in respect to spatial dispersal patterns, germination synchronization, and patterns of genetic diversity within and among populations. Raphanus is a Mediterranean genus comprising two closely related allopatric wild annuals, R. raphanistrum and R. pugioniformis and the cultivated R. sativus. Population-based threshold models will be used to explain eco-physiological regulation of seed dormancy /germination by the environment. In this respect we hypothesize that germination of R. raphanistrum occurs upon long imbibition, while pericarp-mediated mechanical dormancy of R. pugioniformis is released only after decomposition of the pericarp by microbial activity or abrasion. The results of our project will provide insight into adaptive processes in annual Brassicaceae and we expect that this interdisciplinary study will stimulate Israeli and Palestinian students to join this research area.

Collaborating organisations:
University of Osnabrück (Germany), Klaus Mummenhoff, (coordinating PI);
Agricultural Research Organization (ARO, Israel), O. Barazani (Co-I);
Hebrew University of Jerusalem (Israel), Jotham Ziffer-Berger (Co-I);
Thameen Hijawi, Al Quds University, Palestinian Authority (AQU),
Association for Integrated Rural Development, Palestinian Authority (AIRD), Nasser Samara (Co-I);
Associated collaborating partners:
Pinchas Fine, Agricultural Research Organization, Israel;
Oren Ostersetzer, Hebrew University of Jerusalem, Israel;
Erik Westberg, KWS Saat SE, Einbeck, Germany;
Gerhard Leubner and Tina Steinbrecher, Royal Holloway University of London, UK.