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bioRxiv · 10.1101/2025.09.14.676089

Wild genes to the rescue: High-throughput genomics uncovers the wild source of broomrape resistance in sunflower

Sisou, D.·Ziadne, H.·Eizenberg-Weiss, M.·Eizenberg, H.·Hubner, S.
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Abstract

O_LIThe ongoing evolutionary arms race between crop plants and their parasites necessitates a constant exploration of new genetic resistance. Broomrape (Orobanche cumana), a devastating parasitic plant, presents a formidable challenge to sunflower production, yet the genetic mechanisms underlying host resistance are still largely unknown. C_LIO_LITo address this gap, we developed a high-throughput phenotyping platform to quantify root infestation in a highly diverse sunflower association mapping (SAM) population. Using a dual GWAS approach with both SNPs and k-mers, we were able to pinpoint the genetic basis of resistance. C_LIO_LIOur findings validate previously identified QTLs with greater resolution and reveal several novel candidate genes conferring resistance, including putative leucine-rich repeat receptor kinases. Critically, the k-mer mapping approach circumvented reference genome bias, highlighting key introgressions from wild Helianthus species that have contributed to broomrape resistance. C_LIO_LIThis research provides a powerful methodology for gene discovery and demonstrates that wild relatives remain a vital source of genetic material, offering breeders a significant advantage in the ongoing battle against rapidly evolving parasites. C_LI

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Sisou, D., Ziadne, H., Eizenberg-Weiss, M., Eizenberg, H., Hubner, S.. 2025-09-16. Wild genes to the rescue: High-throughput genomics uncovers the wild source of broomrape resistance in sunflower. https://doi.org/10.1101/2025.09.14.676089

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