title: Fine-Mapping the Wheat Snn1 Locus Conferring Sensitivity to the Parastagonospora nodorum Necrotrophic Effector SnTox1 Using an Eight Founder Multiparent Advanced Generation Inter-Cross Population.
abstract: The necrotrophic fungus Parastagonospora nodorum is an important pathogen of one of the world's most economically important cereal crops, wheat (Triticum aestivum L.). P. nodorum produces necrotrophic protein effectors that mediate host cell death, providing nutrients for continuation of the infection process. The recent discovery of pathogen effectors has revolutionized disease resistance breeding for necrotrophic diseases in crop species, allowing often complex genetic resistance mechanisms to be broken down into constituent parts. To date, three effectors have been identified in P. nodorum. Here we use the effector, SnTox1, to screen 642 progeny from an eight-parent multiparent advanced generation inter-cross (i.e., MAGIC) population, genotyped with a 90,000-feature single-nucleotide polymorphism array. The MAGIC founders showed a range of sensitivity to SnTox1, with transgressive segregation evident in the progeny. SnTox1 sensitivity showed high heritability, with quantitative trait locus analyses fine-mapping the Snn1 locus to the short arm of chromosome 1B. In addition, a previously undescribed SnTox1 sensitivity locus was identified on the long arm of chromosome 5A, termed here QSnn.niab-5A.1. The peak single-nucleotide polymorphism for the Snn1 locus was converted to the KASP genotyping platform, providing breeders and researchers a simple and cheap diagnostic marker for allelic state at Snn1.
authors.affiliation: John Bingham Laboratory, National Institute of Agricultural Botany (NIAB), Huntington Road, Cambridge, CB3 0LE, United Kingdom james.cockram@niab.com.
authors.forename: James
authors.initials: J
authors.lastname: Cockram
authors.affiliation: John Bingham Laboratory, National Institute of Agricultural Botany (NIAB), Huntington Road, Cambridge, CB3 0LE, United Kingdom Department of Drug Science and Products for Health, University of Messina, Sicily, 98122, Italy.
authors.forename: Alice
authors.initials: A
authors.lastname: Scuderi
authors.affiliation: John Bingham Laboratory, National Institute of Agricultural Botany (NIAB), Huntington Road, Cambridge, CB3 0LE, United Kingdom.
authors.forename: Toby
authors.initials: T
authors.lastname: Barber
authors.affiliation: Centre for Crop Disease Management, Curtin University, WA6845, Australia.
authors.forename: Eiko
authors.initials: E
authors.lastname: Furuki
authors.affiliation: John Bingham Laboratory, National Institute of Agricultural Botany (NIAB), Huntington Road, Cambridge, CB3 0LE, United Kingdom.
authors.forename: Keith A
authors.initials: KA
authors.lastname: Gardner
authors.affiliation: John Bingham Laboratory, National Institute of Agricultural Botany (NIAB), Huntington Road, Cambridge, CB3 0LE, United Kingdom.
authors.forename: Nick
authors.initials: N
authors.lastname: Gosman
authors.affiliation: John Bingham Laboratory, National Institute of Agricultural Botany (NIAB), Huntington Road, Cambridge, CB3 0LE, United Kingdom Faculty of Life Sciences, University of Manchester, M13 9PL, United Kingdom.
authors.forename: Radoslaw
authors.initials: R
authors.lastname: Kowalczyk
authors.affiliation: Centre for Crop Disease Management, Curtin University, WA6845, Australia.
authors.forename: Huyen P
authors.initials: HP
authors.lastname: Phan
authors.affiliation: John Bingham Laboratory, National Institute of Agricultural Botany (NIAB), Huntington Road, Cambridge, CB3 0LE, United Kingdom.
authors.forename: Gemma A
authors.initials: GA
authors.lastname: Rose
authors.affiliation: Centre for Crop Disease Management, Curtin University, WA6845, Australia.
authors.forename: Kar-Chun
authors.initials: KC
authors.lastname: Tan
authors.affiliation: Centre for Crop Disease Management, Curtin University, WA6845, Australia.
authors.forename: Richard P
authors.initials: RP
authors.lastname: Oliver
authors.affiliation: John Bingham Laboratory, National Institute of Agricultural Botany (NIAB), Huntington Road, Cambridge, CB3 0LE, United Kingdom.
authors.forename: Ian J
authors.initials: IJ
authors.lastname: Mackay
mesh_terms: D001203:Ascomycota / Q000472:pathogenicity; D032461:Chromosomes, Plant / Q000235:genetics; D060467:Disease Resistance / Q000235:genetics*; D008040:Genetic Linkage; D056426:Genetic Loci; D006824:Hybridization, Genetic; D009183:Mycotoxins / Q000633:toxicity; D020641:Polymorphism, Single Nucleotide; D014908:Triticum / Q000235:genetics* / Q000382:microbiology
chemical_list: D009183:Mycotoxins
keywords: MPP; Multiparent Advanced Generation Inter-Cross (MAGIC); diagnostic genetic markers; fungal protein effectors; high-density crop genotyping; multiparent genetic mapping populations; multiparental populations; plant disease resistance breeding