Submitted by Jane Durkin on Tue, 25/11/2025 - 12:28
Studying Plant Sciences at Cambridge can open up a wealth of career opportunities. In this series, we hear from Plant Sciences alumni about their experiences of studying here, how it shaped their careers and what they are doing now.
If you would like your alumni story featured, please email us at alumni@plantsci.cam.ac.uk.
About Niels
Dr Simon ‘Niels’ Groen completed his PhD in Plant Sciences in 2014, studying at Magdalene College and working with Professor John Carr in the Virology and Molecular Plant Pathology group.
Following his doctorate, he moved to the United States, working as a postdoctoral researcher at the Universities of Arizona and California Berkeley, before moving to New York University (NYU) as a Gordon and Betty Moore Foundation fellow.
In 2021 he established his own research group at the University of California Riverside, looking at the evolution of interactions between parasitic nematodes and their plant and animal hosts, with particular focus on the role of plant defensive chemicals in shaping host-parasite interactions across the food chain.
Key questions include: How do plants defend themselves against plant-parasitic nematodes? When animals eat toxic plants, could that help them fight off nematode infections of their own? How do nematode parasites handle plant and animal defenses? What are the genes involved?
As well as improving our understanding of how host-parasite interactions may evolve in the future, he hopes that uncovering which genes shape these interactions will help develop strategies to minimise plant and crop damage caused by parasitic nematodes.
What is your favourite memory from your time in the Department of Plant Sciences?
The Department was a wonderfully social and welcoming place to be. I loved every minute of my time there.
There are many memories I cherish, but among my favorite ones are the football games at Downing College and Parker’s Piece; punting on the Cam, attending college dinners, and visiting the beer festival and pubs with the lab; and all the hours spent in the tearoom.
Enjoying coffee, tea, and fermented beverages in the tearoom with everyone was not only a fun social activity but also led to very stimulating brainstorming sessions on the amazing science that people were doing.
How did your time in the Department influence your career journey?
My fascination with plants and their responses to ever-changing environmental conditions began when I was a child.
I grew up in a village in the northwest of the Netherlands and worked as a ‘ziekzoeker’ in tulip fields outside of school hours. A ‘ziekzoeker’ is someone who looks for diseased plants and my job was to find variegated white and red tulips – the ones you’d recognize from a golden-age Dutch still life painting. Tulip variegation can be genetic but can also be caused by a virus spread by aphids which weakens the plant over time.
After spending time as a Master’s student at Harvard researching how plant immune systems integrate signals when under attack by microbes and insect herbivores, I was keen to work on the insect-transmitted viral diseases that plagued the tulip fields of my childhood.
You could imagine my joy when John told me I could do my PhD research in his group!
Together with lab mates, including Jack Westwood, Trisna Tungadi, Sanjie Jiang and Alex Murphy, I was investigating the molecular mechanisms of how plant virus infections would change plant interactions with pollinators and virus-transmitting aphids through alterations in odour and defensive chemical profiles.
We found that the effect of an infected plant on insects tended to benefit virus transmission – be it directly or indirectly. The plant’s phenotype became to some extent an extended phenotype of the virus – an idea originally coined by Richard Dawkins in ‘The Extended Phenotype’ in 1982.
One highlight was that our findings in model plants had translational value for crops such as beans and tomato. This is something which John’s group continues to work on with major international collaborations today.
My future career benefitted enormously from my experiences in the Department. John’s lab gave me a strong foundation in genetics and molecular biology and taught me that some of the most exciting science can be done as part of an interdisciplinary team.
John and others in the Department showed me the importance of kindness and understanding when advising students and postdocs. I strive to pay this forward to my own mentees every day.
What have you gone on to do since leaving the Department?
During my time in the Department, I became fascinated by the role that plant defensive chemicals play in shaping species interactions. I continued to study these as a postdoc with Noah Whiteman in Arizona and at the University of California Berkeley.
Here, we focused on the evolution of interactions between milkweeds and the monarch butterfly and found out how the monarch evolved resistance to the cardenolide toxins that milkweeds make. While this work mostly revolved around a single gene, typically several genes are involved in an organisms’ evolutionary responses.
As a Moore Foundation fellow with Michael Purugganan at NYU I learned about the latest developments in evolutionary genomics and systems biology while investigating patterns of natural selection on gene expression in rice populations. We grew these under wet and dry field conditions with our collaborators at the International Rice Research Institute in the Philippines.
In both these postdoc projects, the familiarity with genetics and molecular biology I gained in the Department allowed me to design functional genetics experiments that enabled moving from correlation to causation. We were able to retrace evolution by inferring how genetic variants impacted organismal fitness.
I was delighted when I then got the opportunity to join the Department of Nematology at the University of California Riverside and start my own lab. Aside from our research on the evolution of host-parasite interactions in systems as diverse as milkweeds (and other plants), monarchs, and mice, I teach introductory and advanced courses in genetics to upper-division undergraduate students.
It still amazes me to see how much virology and molecular plant pathology has contributed to our understanding of how cellular processes work. And the tools that sprang from these fields still come in very handy in our functional genetics experiments.
What do you enjoy most about what you are doing now?
I really enjoy that as PI I get to interact with many intelligent and driven people, who are engaged in such a variety of interesting activities they are passionate about.
Not only is the science in Southern California and in my field super exciting, but outside of work it’s wonderful to get to explore the local deserts and mountains and to attend concerts which are part of the thriving music scene here.
Recently we even organized a science and music event, ‘Earworm’. It was a great chance for people from across the region to gather and listen to a combination of classical music and popular science talks about parasitic nematodes. I hope we can keep doing outreach activities like this for years to come!
Image: Niels Groen sampling rice roots for gene expression measurements, arbuscular mycorrhizal fungi interactions and plant-parasitic nematode infection at the International Rice Research Institute (IRRI) in Los Baños, the Philippines.