title: Toward a better understanding of the genomic region harboring Fusarium head blight resistance QTL Qfhs.ndsu-3AS in durum wheat.
abstract: New molecular markers were developed and mapped to the FHB resistance QTL region in high resolution. Micro-collinearity of the QTL region with rice and Brachypodium was revealed for a better understanding of the genomic region. The wild emmer wheat (Triticum dicoccoides)-derived Fusarium head blight (FHB) resistance quantitative trait locus (QTL) Qfhs.ndsu-3AS previously mapped to the short arm of chromosome 3A (3AS) in a population of recombinant inbred chromosome lines (RICLs). This study aimed to attain a better understanding of the genomic region harboring Qfhs.ndsu-3AS and to improve the utility of the QTL in wheat breeding. Micro-collinearity of the QTL region with rice chromosome 1 and Brachypodium chromosome 2 was identified and used for marker development in saturation mapping. A total of 42 new EST-derived sequence tagged site (STS) and simple sequence repeat (SSR) markers were developed and mapped to the QTL and nearby regions on 3AS. Further comparative analysis revealed a complex collinearity of the 3AS genomic region with their collinear counterparts of rice and Brachypodium. Fine mapping of the QTL region resolved five co-segregating markers (Xwgc1186/Xwgc716/Xwgc1143/Xwgc501/Xwgc1204) into three distinct loci proximal to Xgwm2, a marker previously reported to be closely linked to the QTL. Four other markers (Xwgc1226, Xwgc510, Xwgc1296, and Xwgc1301) mapped farther proximal to the above markers in the QTL region with a higher resolution. Five homozygous recombinants with shortened T. dicoccoides chromosomal segments in the QTL region were recovered by molecular marker analysis and evaluated for FHB resistance. Qfhs.ndsu-3AS was positioned to a 5.2 cM interval flanked by the marker Xwgc501 and Xwgc510. The recombinants containing Qfhs.ndsu-3AS and new markers defining the QTL will facilitate utilization of this resistance source in wheat breeding.
authors.affiliation: Departments of Plant Sciences, North Dakota State University, Fargo, ND, 58108, USA.
authors.forename: Xianwen
authors.initials: X
authors.lastname: Zhu
authors.affiliation: Departments of Plant Pathology, North Dakota State University, Fargo, ND, 58108, USA.
authors.forename: Shaobin
authors.initials: S
authors.lastname: Zhong
authors.affiliation: The Red River Valley Agricultural Research Center, USDA-ARS, Fargo, ND, 58102, USA.
authors.forename: Shiaoman
authors.initials: S
authors.lastname: Chao
authors.affiliation: The Western Regional Research Center, USDA-ARS, Albany, CA, 94710, USA.
authors.forename: Yong Qiang
authors.initials: YQ
authors.lastname: Gu
authors.affiliation: The Cereal Disease Laboratory, USDA-ARS, 1551 Lindig Street, St. Paul, MN, 55108, USA.
authors.forename: Shahryar F
authors.initials: SF
authors.lastname: Kianian
authors.affiliation: Departments of Plant Sciences, North Dakota State University, Fargo, ND, 58108, USA.
authors.forename: Elias
authors.initials: E
authors.lastname: Elias
authors.affiliation: Departments of Plant Sciences, North Dakota State University, Fargo, ND, 58108, USA. xiwen.cai@ndsu.edu.
authors.forename: Xiwen
authors.initials: X
authors.lastname: Cai
mesh_terms: D058431:Brachypodium / Q000235:genetics; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D060467:Disease Resistance / Q000235:genetics*; D020224:Expressed Sequence Tags; D005670:Fusarium; D005819:Genetic Markers; D018745:Genome, Plant; D005838:Genotype; D018895:Microsatellite Repeats; D012275:Oryza / Q000235:genetics; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D040641:Quantitative Trait Loci; D016324:Sequence Tagged Sites; D014908:Triticum / Q000235:genetics* / Q000382:microbiology
chemical_list: D005819:Genetic Markers