Dr. Maria Zwyssig

Education

November 2019 – present: PhD Student, Plant Pathology Group, Institute of Integrative Biology, ETH Zürich.

2017-2019 Master of Science in Microbiology and Immunology, ETH Zürich.

2014-2017 Bachelor of Science in Biology, ETH Zürich.

Current Project

Plant beneficial pseudomonads are promising candidates for pest control in agriculture. The Pseudomonas protegens and P. chlororaphis subgroups are efficient root colonizers with disease-suppressive as well as insecticidal activities against plant insect pests. Their ability to switch between root and insect colonizing lifestyles make them highly interesting tools to study for potential use as pest control. Although many traits enabling root colonization and insect pathogenicity are already known, it is not clearly understood how these insecticidal Pseudomonas have adapted to living in an insect and how they switch between their lifestyles.

In the first part of my thesis, I aim to perform an experimental evolution with P. protegens CHA0 consisting of cycles of repeated feeding to larvae of the crop pest Plutella xylostella. Analysis of evolved clones for genomic changes and alterations in insect-bacteria and plant-bacteria interactions will provide new knowledge on the adaption of plant beneficial pseudomonads to insects as well as provide insight on how they switch between their lifestyles.

Using combinations of insecticidal Pseudomonas and entomopathogenic nematodes might increase the control efficiency, however single interactions of combination members are important to understand beforehand. In the second part of my thesis, I will investigate interactions of insecticidal Pseudomonas first with entomopathogenic nematode associated bacteria and second with the nematodes themselves. The acquired knowledge might eventually be used to build compatible and stable consortia for the use in pest control.

Research Interests

- Microbial interactions
- Pathogen adaptation to hosts
- Biological control