# Pan-genomic analysis of sunflower finds 1,433 candidate disease-resistance genes, 198 absent from reference

- Published: 2026-11-14 06:03 UTC
- Section: Life & Health › Agritech & food
- Tags: sunflower breeding, pan-genomic analysis, candidate disease-resistance genes, NBS-containing genes, Sclerotinia sclerotiorum, wild sunflower relatives, LTR retrotransposons, linkage disequilibrium, differential gene expression
- URL: https://realtech.media/news/rt-88424c9fe9e3a7baa451beca_pan_genomic_analysis/

**Researchers combined reference annotation with sequencing of 100 cultivated and 49 wild sunflower accessions, giving breeders a ranked list of genes for functional validation.**

![Pan-genomic analysis of sunflower finds 1,433 candidate disease-resistance genes, 198 absent from reference](https://realtech.media/media/2026/11/c8f417da787cca10.jpg)
*Björn S., Wikimedia Commons, CC BY-SA 3.0*

Researchers have expanded the catalogue of candidate disease-resistance genes in sunflower by combining reference-genome annotation with genomic and transcriptomic analyses of many accessions, according to a paper in Plant Molecular Biology (doi.org). They analysed whole-genome sequencing data from 100 cultivated sunflower accessions and 49 wild relatives. In total, 1,433 candidate disease-resistance genes were identified [1].

Sunflower genotypes differ substantially in resistance to pathogens, and an important fraction of the resistance used in breeding comes from wild relatives. Many of the underlying genes, however, remain unknown, which limits targeted breeding [1].

## How the candidates were found

The authors first complemented the existing reference annotation with de novo prediction of additional NBS-containing genes. They then assembled sequencing reads that did not map to the reference genome, which revealed non-reference candidate pan-genes [1]. The final set contains 1,235 reference-based genes and 198 non-reference pan-genes [1].

Reference genes were distributed unevenly across the genome. A large proportion were arranged in clusters, and these clusters lay significantly closer to LTR retrotransposons than singleton genes did [1]. The team also characterised sequence and structural variation across the panel, including SNPs, INDELs and large deletions [1].

## Expression and prioritisation

The genomic data were combined with transcriptomic responses to inoculation with Sclerotinia sclerotiorum. In at least one of two contrasting genotypes, 548 candidate genes were differentially expressed [1].

Thirty-three candidate genes were located in linkage disequilibrium with previously reported disease-resistance-associated loci. Ten of them were also differentially expressed after inoculation, and eight were polymorphic [1].

The authors state that the analyses expand the catalogue of candidate genes and genomic variation available in sunflower. They describe the result as a prioritised set of candidates and genetic resources for downstream functional validation and breeding applications [1]. The work identifies candidates; the function of these genes in resistance has not yet been confirmed.

## Sources

1. [doi.org](https://doi.org/10.1007/s11103-026-01768-w)
2. [bioengineer.org](https://bioengineer.org/pan-genomic-analysis-identifies-candidate-disease-resistance-genes-for-sunflower-breeding)

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Source: RealTech, realtech.media — https://realtech.media/news/rt-88424c9fe9e3a7baa451beca_pan_genomic_analysis/