PhD defence
Ecological implications of virus occurrences in soils
- R. Wang
- Date
- Tuesday 9 June 2026
- Time
- Location
-
Academy Building
Rapenburg 73
2311 GJ Leiden
Supervisor(s)
- dr. S.E. Hannula
- Prof.dr.ir. P. M. van Bodegom
- dr. K. Mason-Jones
Summary
Soil viruses are abundant but their ecological roles are still poorly understood. This thesis investigates how soil viruses interact with microbial communities and influence carbon cycling. We combined culture-based screening, metatranscriptomics, controlled microcosm experiments, and stable isotope probing to study viruses across different biological scales.
First, we found that RNA viruses infecting saprotrophic fungi are rare, despite high viral diversity reported in environmental datasets. This suggests that detecting viral sequences does not necessarily mean widespread infection of hosts. Next, we showed that bacteriophages affect bacterial communities in a highly context-dependent way. Their effects varied across soils and were influenced by fungal presence, highlighting the importance of cross-kingdom interactions. I then demonstrated that viruses can alter soil carbon cycling, but these effects were inconsistent and depended on soil properties and microbial interactions. Finally, using 18O stable isotope probing, I found that only a small fraction of bacteria are actively growing at a given time, which limits the potential hosts available for viral infection.
These findings show that the impact of soil viruses is not fixed but depends on environmental conditions and microbial interactions. By improving our understanding of how viruses influence these systems, this work contributes to better predictions of soil functioning under environmental change.
PhD dissertations
Approximately one week after the defence, PhD dissertations by Leiden PhD students are available digitally through the Leiden Repository, that offers free access to these PhD dissertations. Please note that in some cases a dissertation may be under embargo temporarily and access to its full-text version will only be granted later.
Press enquiries (journalists only)
+31 (0)71 527 1521
nieuws@leidenuniv.nl
General information
Beadle's Office
pedel@bb.leidenuniv.nl
+31 71 527 7211