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ARS Home » Midwest Area » St. Paul, Minnesota » Cereal Disease Lab » Research » Publications at this Location » Publication #413750
Research Project: Surveillance, Pathogen Biology, and Host Resistance of Cereal Rusts

Location: Cereal Disease Lab

Title: A high-resolution haplotype pangenome uncovers somatic hybridization, recombination and intercontinental migration in oat crown rust

Author
item HENNINGSEN, EVA - Commonwealth Scientific And Industrial Research Organisation (CSIRO)
item LEWIS, DAVID - Commonwealth Scientific And Industrial Research Organisation (CSIRO)
item NAZARENO, ERIC - University Of Minnesota
item HUANG, YUNG-FEN - National Central University - Taiwan
item STEFFENSON, BRIAN - University Of Minnesota
item BOESEN, BRENDAN - Commonwealth Scientific And Industrial Research Organisation (CSIRO)
item Kianian, Shahryar
item STONE, ERIC - Australian National University
item DODDS, PETER - Commonwealth Scientific And Industrial Research Organisation (CSIRO)
item SPERSCHNEIDER, JANA - Commonwealth Scientific And Industrial Research Organisation (CSIRO)

Submitted to: bioRxiv
Publication Type: Rapid Release Publication
Publication Acceptance Date: 4/1/2024
Publication Date: N/A
Citation: N/A
DOI: https://doi.org/10.1101/2024.03.27.583983

Interpretive Summary: Oat crown rust is a devastating disease caused by Puccinia coronata f. sp. avenae. The pathogen has high evolutionary potential and can generate new virulences through mutations, meiotic recombination, and reassortment of virulence factors with the aid of its alternate host, common buckthorn (Rhamnus cathartica). Losses due to the disease could reach up to 50% in certain parts of the U.S. Molecular evidence shows that sexuality is a clear driver of this rapid virulence evolution in USA populations and influences population structure in Sweden. However, asexual Pca populations have also been observed to gain virulence following R gene deployment. Using phylogenetics, comparative genomics, and k-mer containment approaches, we discovered somatic hybridizations implicating global

Technical Abstract: Basidiomycetes like the rust fungi have complex reproductive cycles and dikaryotic life stages which influence their population structure and evolution. To investigate the global diversity, mating type system and role of somatic hybridization in the oat pathogen Puccinia coronata f. sp. avenae, we characterized a collection of Taiwanese and Australian isolates with whole genome sequencing and constructed an atlas of 30 chromosome-level, fully-phased haplotypes from 15 USA and Australian isolates. Using phylogenetics, comparative genomics, and k-mer containment approaches, we discovered somatic hybridizations implicating global migration of Pca and extensive recombination of USA haplotypes. The limitations of assuming evolutionary history from phenotyping are demonstrated