Genetic Resistance Mechanisms in Potato Late Blight

Potato late blight, caused by the oomycete Phytophthora infestans, remains a principal threat to global food security. Genetic resistance mechanisms centre on the deployment of resistance (R) genes encoding intracellular immune receptors, predominantly nucleotide-binding leucine-rich repeat (NLR) proteins, which detect specific pathogen effectors and trigger defence responses. Recognition of RXLR effectors by cognate NLRs often elicits a rapid hypersensitive response, localised cell death that restricts pathogen spread. Durability of resistance can be enhanced by stacking multiple R genes with distinct recognition spectra or by tapping non-host NLR networks. Advances in genome sequencing and effector profiling have accelerated discovery of novel R genes from wild Solanum species and non-host plants. Modern strategies, including pan-NLRome assembly, marker-free cisgenic transformation and genomic-assisted breeding, aim to combine broad-spectrum resistance with agronomic traits, thereby reducing reliance on chemical control and improving sustainability of potato production worldwide.

Research from Nature Portfolio

Recent studies have generated high-quality reference genomes for wild Solanum americanum accessions and defined a pan-NLRome comprising the full complement of immune receptor genes. Systematic screening against a library of over 300 P. infestans RXLR effectors identified three novel NLRs—Rpi-amr4, R02860 and R04373—that confer recognition of cognate avirulence proteins. Cloning of these genes has established precise targets for engineering durable late blight resistance in cultivated potato and offers a template for similar approaches in other crops.

Genetic Resistance Mechanisms in Potato Late Blight publication trend

The graph below shows the total number of articles in genetic resistance mechanisms in potato late blight across all publications each year (not limited to Nature Index journals).

Technical terms

Nucleotide-binding leucine-rich repeat (NLR) protein: Intracellular immune receptor that recognises pathogen effectors via a conserved nucleotide-binding domain and leucine-rich repeats.

RXLR effector: Secreted oomycete protein bearing an RXLR motif that facilitates translocation into host cells to manipulate plant immunity.

Cisgenesis: Genetic engineering method introducing genes from sexually compatible species without foreign DNA, preserving varietal integrity.

Hypersensitive response: Rapid, localised plant cell death at infection sites that limits pathogen colonisation.

References

1. Solanum americanum genome-assisted discovery of immune receptors that detect potato late blight pathogen effectors. Nature Genetics (2023).
2. Insights on cisgenic plants with durable disease resistance under the European Green Deal. Trends in Biotechnology (2023).
3. Nucleotide‐binding leucine‐rich repeat network underlies nonhost resistance of pepper against the Irish potato famine pathogen Phytophthora infestans. Plant Biotechnology Journal (2023).
4. Identification and mapping of Rpi-blb4 in diploid wild potato species Solanum bulbocastanum. The Crop Journal (2023).