title: Fine mapping of the stem rust resistance gene SrTA10187.
abstract: SrTA10187 was fine-mapped to a 1.1 cM interval, candidate genes were identified in the region of interest, and molecular markers were developed for marker-assisted selection and Sr gene pyramiding. Stem rust (Puccinia graminis f. sp. tritici, Pgt) races belonging to the Ug99 (TTKSK) race group pose a serious threat to global wheat (Triticum aestivum L.) production. To improve Pgt host resistance, the Ug99-effective resistance gene SrTA10187 previously identified in Aegilops tauschii Coss. was introgressed into wheat, and mapped to the short arm of wheat chromosome 6D. In this study, high-resolution mapping of SrTA10187 was done using a population of 1,060 plants. Pgt resistance was screened using race QFCSC. PCR-based SNP and STS markers were developed from genotyping-by-sequencing tags and SNP sequences available in online databases. SrTA10187 segregated as expected in a 3:1 ratio of resistant to susceptible individuals in three out of six BC3F2families, and was fine-mapped to a 1.1 cM region on wheat chromosome 6DS. Marker context sequence was aligned to the reference Ae. tauschii genome to identify the physical region encompassing SrTA10187. Due to the size of the corresponding region, candidate disease resistance genes could not be identified with confidence. Comparisons with the Ae. tauschii genetic map developed by Luo et al. (PNAS 110(19):7940-7945, 2013) enabled identification of a discrete genetic locus and a BAC minimum tiling path of the region spanning SrTA10187. Annotation of pooled BAC library sequences led to the identification of candidate genes in the region of interest-including a single NB-ARC-LRR gene. The shorter genetic interval and flanking KASP™ and STS markers developed in this study will facilitate marker-assisted selection, gene pyramiding, and positional cloning of SrTA10187.
authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue Street, Room A286, East Lansing, MI, 48824, USA.
authors: Andrew T
authors: AT
authors: Wiersma
authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue Street, Room A286, East Lansing, MI, 48824, USA.
authors: Linda K
authors: LK
authors: Brown
authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue Street, Room A286, East Lansing, MI, 48824, USA.
authors: Elizabeth I
authors: EI
authors: Brisco
authors: Department of Plant Biology, Michigan State University, 612 Wilson Rd, Room 166, East Lansing, MI, 48824, USA.
authors: Tiffany L
authors: TL
authors: Liu
authors: Department of Plant Biology and Center for Genomics-Enabled Plant Science, Michigan State University, 612 Wilson Rd, Room 166, East Lansing, MI, 48824, USA.
authors: Kevin L
authors: KL
authors: Childs
authors: Department of Plant Pathology, Wheat Genetics Resource Center, Kansas State University, 4011 Throckmorton Plant Sciences Center, Manhattan, KS, 66506, USA.
authors: Jesse A
authors: JA
authors: Poland
authors: Department of Plant Science, South Dakota State University, Plant Science-Box 2140C, Brookings, SD, 57007, USA.
authors: Sunish K
authors: SK
authors: Sehgal
authors: Department of Plant, Soil and Microbial Sciences, Michigan State University, 1066 Bogue Street, Room A286, East Lansing, MI, 48824, USA. eolson@msu.edu.
authors: Eric L
authors: http://orcid.org/0000-0002-4527-1723
authors: EL
authors: Olson
mesh_terms: D001487:Basidiomycota; D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D060467:Disease Resistance / Q000235:genetics*; D017343:Genes, Plant; D008040:Genetic Linkage; D010641:Phenotype; D020161:Physical Chromosome Mapping; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D006109:Poaceae / Q000235:genetics; D020641:Polymorphism, Single Nucleotide; D016324:Sequence Tagged Sites; D014908:Triticum / Q000235:genetics* / Q000382:microbiology