The core of the various collections at the Institute of Organismic and Molecular Evolutionary Biology consists of plant samples preserved in alcohol (currently around 3,000 pieces), which have often been collected on research trips or field trips. This part of the collection is based on the collection of Prof. Dr. Regine Classen-Bockhoff, who had already created it at her previous places of work from 1985. It has been continuously expanded at the Mainz location since 1998. There is also a collection of dried fruits, seeds and other plant parts for teaching.
In addition to the collections currently included in teaching and research, there is a historical inventory of plant preparations in alcohol, which reflects botanical research at JGU since it was refounded in 1946. Exemplary specimens are kept for documentary purposes. There are also over a hundred teaching boards, some of which are handmade and colored, which were used in lectures until a few years ago. In addition, an almost complete collection of the pollen-collecting wild bees in the Botanical Garden, which was created and identified in the 1980s. Furthermore, there are scanning electron microscopic (SEM) preparations from various families of flowering plants.
The value of the collection lies in the provision of (rare) plant material. Doctoral students, postdocs and students use them for their research work, and lecturers for teaching. Many samples are stored as evidence of the research results obtained. In particular, the interplay of the alcohol collection with the live collection in the Botanical Garden and the dry collection in the herbarium is of great importance. For example, there is a special collection on the genus Salvia (sage) with alcohol preparations and silica samples for molecular analyses, which corresponds to a collection of live specimens from the Botanical Garden and specimens in the herbarium. More than 150 species, particularly from Europe, Mexico, California and South Africa, are documented in this way. The South African Bruniaceae and the African representatives (Gabon) of the Marantaceae from their natural habitats are almost completely present in at least two collections, so that comparative investigations are possible.
The collection of Wilhelm Troll, founder of the Botanic Garden, is part of the Botanical Collections and includes scientific drawings, glass slides and photographs as well as manuscripts and alcohol preparations that document the history of the development of the Botanical Garden.