The Biodiversity and Evolution of Plants working group and the Botanical Garden (headed by Prof. Dr. Dirk Albach) at the Institute for Biology and Environmental Sciences (BU) at the Carl von Ossietzky University in Oldenburg deal with the importance of intraspecific diversity for evolution and survival of plant species. These questions are analyzed with the help of studies of the phenotype but above all also DNA-based analyzes of the genome and the transcriptome as well as endophytic microorganisms, i.e. fungi and bacteria that live inside the plants. Applied aspects of plant breeding appear again and again, e.g. the importance of genetic diversity for yield in agriculture. The working group is active in several national and international research projects in this area. For example, the employees were involved in projects on the evolution of antibiotic ingredients in rhododendrons or on breeding pest-resistant apple varieties. In addition to 3.7 hectares of display areas, the botanical garden also has 1.5 hectares of test areas and, in the working group, modern laboratories with all the necessary equipment for the project. The working group is currently working on the use of clover species and variety diversity in agriculture in the BEESPOKE project funded by the EU (Interreg V A program). The aim of the project is to maintain the yield in the grassland, to make the grassland more drought-resistant and to increase the range of flowers for insect diversity. In this project, the expertise is to be transferred and expanded to horticulture.