Cas Verbeek

This is an picture of me holding up a small tree seedling that I have dug up to study it's mycorrhizal fungi, on sunny day in early spring.

As a PhD-student, I research the fascinating world of interactions between arbuscular mycorrhizal fungi and plants. New evidence shows that many plants might be able to obtain carbon from plant-linking mycorrhizal networks in addition to photosynthesizing, turning our understanding of how plants work upside down. My PhD is all about figuring out which plants can take up carbon from fungi, which fungi allow them to do this and, importantly, how these interactions are structured.


Mixotrophy, arbuscular mycorrhizal fungi, Glomeromycota, metabarcoding, interaction networks, partial mycoheterotrophy

Cas Verbeek

PhD student
Understanding Evolution


Plants taking up carbon from fungi in addition to photosynthesis are called mixotrophic. To find out if plants are mixotrophic on arbuscular mycorrhizal fungi (AMF), I use three lines of research:

  • DNA metabarcoding
  • Isotope analysis
  • Microscopy
  • AMF are microscopic fungi that live inside plant roots. Because microscopic identification is limited, we use DNA-sequencing to identify which fungi are present in the roots of plants.
  • The abundance of stable isotopes (natural variants of common atoms) allow us to determine what the carbon source for the plant was; fungal or photosynthetic. In the same way, if we would look at the stable isotopes in our own bodies, we would be able to tell the difference between vegetarians/vegans and meat-eaters!
  • The microscopic structures of the fungi in roots gives us clues about it’s mixotrophic capabilities.
This picture shows us working in a forest to collect plant roots, on a sunny, early spring day. We have set out a plot with bright orange flags in the ground.
Picture of the microscopic tree-like structures of arbuscular mycorrhizal fungi inside the cells of a plant root.