Unravelling the genetic basis of West European Globodera pallida populations overcoming Gpa5 resistance in potato

Potato cultivation is constantly being threatened by a range of microbial and animal pathogens. Persistent infections by the potato cyst nematode (PCN) species Globodera rostochiensisand G. pallida cause symptoms like stunting, leaf yellowing, and a reduction in tuber size in potato. The losses caused by PCNs amount to an estimated 9% of the global potato production. In PCN control, the use of nematode resistant cultivars plays a key role. However, since the first reports of resistance breaking G. pallida populations in Germany in 2014, the durability of PCN resistance in current potato cultivars has become a matter of concern. By using genome sequencing of offspring of G. pallida populations generated on a large set of potato cultivars with PCN resistance, we have identified a genome region in G. pallida significantly associated with virulence. We suspect that G. pallida virulence on current PCN resistant cultivars is determined by one or more genes located within this region. Our work focusses on the further functional characterization of genes encoding secretory proteins within this region. To this end, we combine spatial and temporal transcriptomics with gene silencing approaches to pinpoint the candidate gene(s) causal for breaking resistance. This will help us to resolve the genetic and molecular basis of virulence in G. pallida populations in North-West Europe. Importantly, this project will also enable making predictions about the durability of PCN resistance in current potato cultivars.