title: Identification of a soybean rust resistance gene in PI 567104B.
abstract: Using a combination of phenotypic screening and molecular, statistical, and linkage analyses, we have mapped a dominant soybean rust resistance gene in soybean PI 567104B. Asian soybean rust (SBR), caused by the fungus Phakopsora pachyrhizi Syd. and P. Syd., is one of the most economically important diseases that affect soybean production worldwide. A long-term strategy for minimizing the effects of SBR is the development of genetically resistant cultivars. The objectives of the study were to identify the location of a rust-resistance (Rpp) gene(s) in plant introduction (PI) 567104B, and to determine if the gene(s) in PI 567104B was different from previously mapped Rpp loci. The progeny of the cross of 'IAR 2001 BSR' × PI 567104B was phenotyped from field assays of the F 2:3 and F 4:5 generations and from a growth chamber assay of 253 F 5:6 recombinant inbred lines (RILs). For the growth chamber, the phenotyping was conducted by inoculation with a purified 2006 fungal isolate from Mississippi. A resistance gene locus on PI 567104B was mapped to a region containing the Rpp6 locus on chromosome 18. The high level of resistance of F 1 plants from two other crosses with PI 567104B as one of the parents indicated that the gene from PI 567104B was dominant. The interval containing the gene is flanked by the simple sequence repeat (SSR) markers Satt131 and Satt394, and includes the SSR markers BARCSOYSSR_18_0331 and BARCSOYSSR_18_0380. The results also indicated that the resistance gene from PI 567104B is different from the Rpp1 to the Rpp4 genes previously identified. To determine if the gene from PI 567104B is different from the Rpp6 gene from PI 567102B, additional research will be required.
authors.affiliation: Department of Agronomy, Iowa State University, Ames, IA, 50011-1010, USA.|Department of Agronomy, Shenyang Agricultural University, 120 Dongling Ave, Shenyang, Liaoning, 110866, China.
authors.forename: Min
authors.initials: M
authors.lastname: Liu
authors.affiliation: Crop Genetics Research Unit, USDA-ARS, Stoneville, MS, 38776, USA.
authors.forename: Shuxian
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Agronomy, Iowa State University, Ames, IA, 50011-1010, USA.
authors.forename: Sivakumar
authors.initials: S
authors.lastname: Swaminathan
authors.affiliation: Department of Agronomy, Iowa State University, Ames, IA, 50011-1010, USA.
authors.forename: Binod B
authors.initials: BB
authors.lastname: Sahu
authors.affiliation: Plant Pathology Department, Iowa State University, Ames, IA, 50011-1010, USA.
authors.forename: Leonor F
authors.initials: LF
authors.lastname: Leandro
authors.affiliation: Department of Agronomy, North Carolina State University, Raleigh, NC, 27695, USA.|Genetic Projects Lead Vegetables Seeds R&D Syngenta Biotechnology Inc, 3054 Cornwallis Rd. Research Triangle Park, Durham, NC, 27709, USA.
authors.forename: Andrea J
authors.initials: AJ
authors.lastname: Cardinal
authors.affiliation: Department of Agronomy, Iowa State University, Ames, IA, 50011-1010, USA.
authors.forename: Madan K
authors.initials: MK
authors.lastname: Bhattacharyya
authors.affiliation: USDA-ARS, Soybean Genomics and Improvement Laboratory, Beltsville Agricultural Research Center, Beltsville, MD, 20705, USA.
authors.forename: Qijian
authors.initials: Q
authors.lastname: Song
authors.affiliation: USDA-ARS, Soybean/Maize Germplasm, Pathology and Genetics Research Unit, and Department of Crop Sciences, University of Illinois at Urbana-Champaign, Urbana, IL, 61801, USA. david.walker@ars.usda.gov.
authors.forename: David R
authors.initials: DR
authors.lastname: Walker
authors.affiliation: Department of Agronomy, Iowa State University, Ames, IA, 50011-1010, USA. scianzio@iastate.edu.
authors.forename: Silvia R
authors.initials: SR
authors.lastname: Cianzio
mesh_terms: D001487:Basidiomycota; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D018744:DNA, Plant / Q000235:genetics; D060467:Disease Resistance / Q000235:genetics*; D005799:Genes, Dominant; D017343:Genes, Plant; D008040:Genetic Linkage; D005819:Genetic Markers; D005838:Genotype; D007178:Inbreeding; D018895:Microsatellite Repeats; D010641:Phenotype; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D017422:Sequence Analysis, DNA; D013025:Glycine max / Q000235:genetics*
chemical_list: D018744:DNA, Plant; D005819:Genetic Markers