Abschlussarbeiten
Wir bearbeiten unsere Themen vornehmlich mittels molekularbiologischer Methoden. Diese werden ergänzt durch Feldarbeiten (Sammeln von Proben, Aufnahme diverser Daten (Merkmalsmessung)) und Wachstumsversuche unter kontrollierten Bedingungen, und komplettiert durch statistische Methoden bei der Analyse. Unter der Rubrik „skills you will develop“ finden Sie eine Liste derjenigen Kompetenzen, die Sie erwerben und auch in einer eigenen Bewerbung angeben können.
Im Folgenden finden Sie mögliche Themen, die in einer Bachelor- oder Masterarbeit bearbeitet werden können. Niveau (BSc oder MSc) und Inhalte können in den meisten Fällen den eigenen, vor allem methodischen, Interessen angepasst werden. Bitte melden Sie sich einfach bei den angegebenen Kontaktpersonen oder sprechen uns nach der Vorlesung an.
We work on our topics primarily by means of molecular biological methods. These are complemented by field work (collection of samples, recording of various data (trait measurement)) and growth experiments under controlled conditions, and completed by statistical methods in the analysis. Under the heading "skills you will develop" you will find a list of those skills that you can acquire and also indicate in your own application.
Below you will find possible topics that can be addressed in a Bachelor's or Master's thesis. Level (BSc or MSc) and content can in most cases be adapted to your own, especially methodological, interests. Please just contact the indicated contact persons or talk to us after the lecture.
Global biodiversity patterns of corticolous myxomycetes (Myxogastrea). Moist chamber experiment and barcoding (BSc/MSc)
Myxomycetes are enigmatic protists, which form exquisitely beautiful fructifications. The inhabit all terrestrial habitats, but make an exception of the general rule that diversity must increase from Arctic zones to the Tropics. The basic question, which arose here: are myxomycetes really rare in constantly humid regions, or do they just rarely form fruiting bodies there? We want to answer this question within Germany, using the existing rainfall gradient from the northeastern (dry) to the southwestern (moist) regions. We will sample the bark of living trees, on which corticolous myxomycetes will develop, cultivate it in moist chambers (mc), and compare the diversity of fruiting species with data from DNA metabarcoding of substrates.
Skills you will develop (for BSc): field work, including substrate sampling and recording metadata (GPS-coordinates, elevation, etc.); moist chamber culture method, work with dissecting microscope, pH-meter, basics of Myxomycetes identification, herbarisation of sporocarps, and preparing material for DNA barcoding.
Skills you will develop (for MSc): The DNA barcoding of biological material (the method applicable for any group of organisms), including spore sampling, robot-assisted extraction and PCR, the editing and aligning of DNA sequences, BLAST search and comparison to a reference data base, phylogeny analysis using maximum likelihood approach. Later, these results will be compared with the metabarcoding data; this method will target the same marker (the first part of the 18S rDNA).
Time: For fieldwork – starting immediately till Nov 2023. Another field season would include the time Apr – Nov 2024. Lab work start in Oct 2023 and Oct 2024, respectively. The moist chamber experiment last typically 2.5–3 months.
The thesis work should be written like a scientific paper (preferentially in English), describing the methods and presenting the results along with data evaluation (annotated species list, species accumulation curve and estimation of the diversity to be expected). For an MSc thesis, this will be extended by a part analysing the molecular data.
Supervisor: Dr. Anastasia Kochergina (stacyscreations86(at)gmail.com); Prof. Martin Schnittler
Gene expression analysis in cloudberry (Rubus chamaemorus) using RNAseq (MSc)
The “SoMoMed” project is aimed at studying cloudberry, Rubus chamaemorus (as well as Drosera rotundifolia), from the peatlands of Europe. Productivity and quality analyses will be carried out for future breeding and cultivation of this plant in paludiculture and use it for medical purposes.
Our working group is responsible for the genotyping and gene expression analysis of cloudberry plants. Genotypes that differ in the production of a medical compound (measured by our colleagues from the pharmaceutical department) will be compared by gene expression using RNA sequencing (RNAseq).
Skills you will develop: The student will participate in data analysis and visualization using a pipeline in Python and R. Data analysis will include transcriptome assembly along with detection and annotation of differentially expressed genes. The result of the study will be a joint publication.
Beginning of the practical work: summer semester 2024 (flexible)
Language: English
Supervisor: Kristina Kuprina, Dr. Manuela Bog
Population genetic study of sundew (Drosera rotundifolia) using ISSR markers (BSc/MSc)
The “SoMoMed” project is aimed at studying round-leaved sundew, Drosera rotundifolia, from the peatlands of Europe. Productivity and quality analyses will be carried out for future breeding and cultivation of this plant in paludiculture and use them for medical purposes.
Our working group is responsible for the genotyping and population study of sundew collected throughout Europe. To date, only a few attempts have been made to characterize the genetic structure of the D. rotundifolia population (in Schleswig-Holstein and South Korea). Our study will be the first study on such a wide geographical scale (Germany, Sweden, Lithuania, Latvia, Switzerland, Iceland (?) and others).
Skills you will develop: The student will acquire and improve skills in laboratory work on DNA extraction, performing PCR for ISSR (Inter Simple Sequence Repeats) and gel electrophoresis, as well as data analysis (using GeneMapper and R) and visualization (in R). The study will result in a joint publication.
Beginning of the practical work: winter semester 2023 (flexible)
Language: English
Supervisor: Kristina Kuprina, Dr. Manuela Bog
Myxomycete model species and moist chamber cultures (BSc)
Model organisms are useful to scientists, they allow us to reproduce experiments and conditions around the world. Physarum polycephalum has been widely used as a model species in myxomycetes. However, it is hardly found in nature and its cultivable strains often lose the ability to fruit. Would it be possible to find a model species accessible in the wild throughout the world?
To answer this question, we are conducting an experiment with moist chamber cultures, using the female cones of different Alnus species. This genus is widely distributed, the cones are easily recognisable, and a few myxomycetes are specialized on this substrate. We already have results from cones collected in Greifswald, and we want to widen the outcomes with cones coming from Spain and Japan. Will this substrate be suitable for growing a model species of myxomycetes?
Skills you will develop: handling cultures, species identification, data management (Excel), use of stereomicroscope and optical microscope, critical analysis of the results. Valuable skills for any kind of biodiversity-directed survey, regardless of the group of organisms.
Which methods will be applied? moist chamber cultures, dichotomous identification keys and specialized literature, semipermanent slides with Hoyer’s medium, ecological statistics.
Supervisor: Maho Inoue, Dr. Ángela López-Villalba
Investigation of the germination of pelleted Typha latifolia seeds (BSc)
This thesis topic belongs to the project Paludi-PROGRESS.You will investigate the germination of pelleted cattail seeds in field sites (close to the Peene River). “Pelleted” meaning seeds that were cleaned and enveloped in a water soluble compound by a company to develop an efficient way for commercial stand establishment and to close gaps in existing stands via sowing.
Skills you will develop: field work, data recording, statistical evaluation, supporting literature search
Which methods will be applied? Manual seeding of pills, manual counting of germinated seeds, data analysis via Excel and R
Supervisor: Constantin Möbius, Dr. Manuela Bog
Fruiting propensity and genetic diversity in Australian Myxomycetes (BSc/MSc)
Myxomycetes inhabit all terrestrial habitats, but their diversity patterns seem to be exceptional: the highest diversity is not found in tropical zones.
We have the hypothesis that the reason is a low fruiting propensity of myxomycetes in constantly wet tropical regions. In this thesis work, you are going to assess that on a transect of substrate samples from southeastern Australia, which cover a rainfall gradient from ca. 4000 to 700 mm annual precipitation.
Samples will be cultivated for 2-3 month in a humid chamber, and we record species, sporocarp numbers, and plasmodia. The cultures will be checked with a dissecting microscope on several days to detect myxomycete fructifications. The method also includes measuring pH of substrate, counting number of sporocarps, collection of mature sporocarps, and preparing material for further barcoding.
This is a suitable thesis work for someone who cannot do longer field stays or cannot work full time on a thesis. You need: time to check mc on all necessary days, a simple laptop for working with the dataset. Data evaluation includes a comparison with two existing data sets (thesis works already written / in prep.): Costa Rica and La Reunion.
Possible extensions (as MSc thesis): A molecular part with subsequent barcoding of fructifications (which is applicable for any group of organisms), including spore sampling, robot-assisted PCR and the editing and aligning of sequences, together with BLAST search and the calculation of phylogenetic trees.
Beginning of the practical work: 2024 (flexible)
What you can learn: Working with cultures, data management and evaluation, insights in a “cryptic” group of organisms, microscopy skills / if extending for a MSc thesis: Barcoding workflow, including PCR, sequencing, editing and aligning of sequences, phylogenetic evaluation
Language: English or German
Supervisor: Dr. Martin Schnittler, Dr. Dmytro Leontyev