Molecular Breeding

, 34:1

High-density mapping of a resistance gene to Ug99 from the Iranian landrace PI 626573


  • Jason D. Zurn
    • Department of Plant PathologyNorth Dakota State University
  • Maria Newcomb
    • USDA-ARS, Cereal Disease Laboratory
  • Matthew N. Rouse
    • USDA-ARS, Cereal Disease Laboratory
  • Yue Jin
    • USDA-ARS, Cereal Disease Laboratory
  • Shiaoman Chao
    • USDA-ARS, Cereal Crops Research Unit
  • Jinita Sthapit
    • Department of Plant PathologyWashington State University
  • Deven R. See
    • USDA-ARS, Wheat Genetics, Quality, Physiology and Disease Research Unit
  • Ruth Wanyera
    • Kenya Agricultural Research Institute
  • Peter Njau
    • Kenya Agricultural Research Institute
  • J. Michael Bonman
    • USDA-ARS, Small Grains and Potato Germplasm Research Unit
  • Robert Brueggeman
    • Department of Plant PathologyNorth Dakota State University
    • Department of Plant PathologyNorth Dakota State University

DOI: 10.1007/s11032-014-0081-8

Cite this article as:
Zurn, J.D., Newcomb, M., Rouse, M.N. et al. Mol Breeding (2014) 34: 1. doi:10.1007/s11032-014-0081-8


Managing wheat stem rust, caused by Puccinia graminis f. sp. tritici (Pgt), is imperative for the preservation of global food security. The most effective strategy is pyramiding several resistance genes into adapted wheat cultivars. A search for new resistance sources to Pgt race TTKSK resistance identified a spring wheat landrace, accession PI 626573, as a potentially novel source of resistance. A cross was made between LMPG-6, a susceptible spring wheat line, and PI 626573 and used to develop a recombinant inbred population to map the resistance. Bulk segregant analysis (BSA) of LMPG-6/PI 626573 F2 progeny determined resistance was conferred by a single dominant gene given the provisional designation SrWLR. The BSA identified nine microsatellite (SSR) markers on the long arm of chromosome 2B associated with the resistant phenotype. Fifteen polymorphic SSRs, including the nine identified in the BSA, were used to produce a linkage map of chromosome 2B, positioning SrWLR in an 8.8 cM region between the SSRs GWM47 and WMC332. This region has been reported to contain the wheat stem rust resistance genes Sr9 and SrWeb, the latter conferring resistance to Pgt race TTKSK. The 9,000 marker Illumina Infinium iSelect SNP assay was used to further saturate the SrWLR region. The cosegregating SNP markers IWA6121, IWA6122, IWA7620, IWA8295, and IWA8362 further delimited the SrWLR region distally to a 1.9 cM region. The present study demonstrates the iSelect assay to be an efficient tool to delimit the region of a mapping population and establish syntenic relationships between closely related species.


WheatStem rustSrWLRiSelectInfiniumSNP

Supplementary material

11032_2014_81_MOESM1_ESM.xlsx (127 kb)
Supplementary material 1 Table S1: An online supplementary file containing the Infinium iSelect SNP map of all 25 linkage groups (XLSX 126 kb)

Copyright information

© Springer Science+Business Media Dordrecht 2014