title: High-density mapping of the major FHB resistance gene Fhb7 derived from Thinopyrum ponticum and its pyramiding with Fhb1 by marker-assisted selection.
abstract: Wheat lines with shortened Th. ponticum chromatin carrying Fhb7 and molecular markers linked to Fhb7 will accelerate the transfer of Fhb7 to breeding lines and provide an important resource for future map-based cloning of this gene. Fusarium head blight is a major wheat disease globally. A major FHB resistance gene, designated as Fhb7, derived from Thinopyrum ponticum, was earlier transferred to common wheat, but was not used in wheat breeding due to linkage drag. The aims of this study were to (1) saturate this FHB resistance gene region; (2) develop and characterize secondary translocation lines with shortened Thinopyrum segments carrying Fhb7 using ph1b; (3) pyramid Fhb7 and Fhb1 by marker-assisted selection. Fhb7 was mapped in a 1.7 cM interval that was flanked by molecular markers XsdauK66 and Xcfa2240 with SSR, diversity arrays technology, EST-derived and conserved markers. KS24-2 carrying Fhb7 was analyzed with molecular markers and genomic in situ hybridization, confirming it was a 7DS.7el2L Robertsonian translocation. To reduce the Thinopyrum chromatin segments carrying Fhb7, a BC1F2 population (Chinese Spring ph1bph1b*2/KS24-2) was developed and genotyped with the markers linked to Fhb7. Two new translocation lines (SDAU1881 and SDAU1886) carrying Fhb7 on shortened alien segments (approximately 16.1 and 17.3% of the translocation chromosome, respectively) were developed. Furthermore, four wheat lines (SDAU1902, SDAU1903, SDAU1904, and SDAU1906) with the pyramided markers flanking Fhb1 and Fhb7 were developed and the FHB responses indicated lines with mean NDS ranging from 1.3 to 1.6 had successfully combined Fhb7 and Fhb1. Three new molecular markers associated with Fhb7 were identified and validated in 35 common wheat varieties. The translocation lines with shortened alien segments carrying Fhb7 (and Fhb1) and the markers closely linked to Fhb7 will be useful for improving wheat scab resistance.
authors.affiliation: State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, 271018, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Guo
authors.affiliation: College of Life Science, Northeast Forest University, Harbin, 150040, Jilin, China.
authors.forename: Xiuli
authors.initials: X
authors.lastname: Zhang
authors.affiliation: State Key Lab of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
authors.forename: Yanlin
authors.initials: Y
authors.lastname: Hou
authors.affiliation: State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, 271018, China.
authors.forename: Jinjin
authors.initials: J
authors.lastname: Cai
authors.affiliation: Department of Agronomy, Purdue University, West Lafayette, IN, 47907-1150, USA.
authors.forename: Xiaorong
authors.initials: X
authors.lastname: Shen
authors.affiliation: State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, 271018, China.
authors.forename: Tingting
authors.initials: T
authors.lastname: Zhou
authors.affiliation: State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, 271018, China.
authors.forename: Huihui
authors.initials: H
authors.lastname: Xu
authors.affiliation: Department of Agronomy, Purdue University, West Lafayette, IN, 47907-1150, USA.
authors.forename: Herbert W
authors.initials: HW
authors.lastname: Ohm
authors.affiliation: State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, 271018, China.
authors.forename: Hongwei
authors.initials: H
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, 271018, China.
authors.forename: Anfei
authors.initials: A
authors.lastname: Li
authors.affiliation: State Key Lab of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, Beijing, 100101, China.
authors.forename: Fangpu
authors.initials: F
authors.lastname: Han
authors.affiliation: State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, 271018, China.
authors.forename: Honggang
authors.initials: H
authors.lastname: Wang
authors.affiliation: State Key Laboratory of Crop Biology, College of Agronomy, Shandong Agricultural University, Taian, 271018, China. lkong@sdau.edu.cn.
authors.forename: Lingrang
authors.initials: L
authors.lastname: Kong
mesh_terms: D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D018744:DNA, Plant / Q000235:genetics; D060467:Disease Resistance / Q000235:genetics*; D005670:Fusarium / Q000472:pathogenicity; D017343:Genes, Plant; D008040:Genetic Linkage; D005819:Genetic Markers; D005838:Genotype; D000069600:Plant Breeding; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D030821:Plants, Genetically Modified / Q000235:genetics; D006109:Poaceae / Q000235:genetics*; D014178:Translocation, Genetic; D014908:Triticum / Q000235:genetics* / Q000382:microbiology
chemical_list: D018744:DNA, Plant; D005819:Genetic Markers