title: Identification of functional genic components of major fusarium head blight resistance quantitative trait loci in wheat cultivar Sumai 3.
abstract: Fusarium head blight (FHB) is a devastating disease worldwide, affecting wheat and other small grains. To identify key wheat genes involved in FHB pathogenesis, 406 FHB-related wheat expressed sequence tags functionally identified in Sumai 3 were investigated for their association with FHB-resistance quantitative trait loci (QTL) Fhb1 and Fhb_6BL in 2010 and 2011. A total of 47 candidate genes were identified by bulk analysis, near-isogenic screening and expression QTL mapping, and were finally mapped to their carrier chromosomes with Chinese Spring nulli-tetra deficiency lines. One gene, designated WFhb1_c1 (wheat Fhb1 candidate gene 1), was both functionally associated with and physically located within Fhb1 and was found to be weakly similar (E = 5e+0) to an Arabidopsis gene encoding pectin methyl esterase inhibitor. Two other genes, designated WFI_6BL1 and WFI_6BL2 (wheat-Fusarium interaction genes 6BL1 and 6BL2), were functionally associated with Fhb_6BL but physically mapped on chromosomes 7D and 5A, respectively. WFI_6BL1 was annotated as a 13- lipoxygenase gene and WFI_6BL2 might encode a PR-4-like protein. Our data suggested that i) Fhb1 seems to contribute to FHB resistance by reducing susceptibility in the first 60 h, ii) Fhb_6BL makes its contribution via the jasmonate-mediated pathways, and iii) wheat seems to activate its defense mechanism in the biotrophic phase of FHB pathogenesis.
authors.affiliation: Department of Biology and Microbiology, South Dakota State University, Brookings, SD, USA.
authors.forename: Yongbin
authors.initials: Y
authors.lastname: Zhuang
authors.forename: Aravind
authors.initials: A
authors.lastname: Gala
authors.forename: Yang
authors.initials: Y
authors.lastname: Yen
mesh_terms: D005670:Fusarium / Q000472:pathogenicity*; D010935:Plant Diseases / Q000382:microbiology*; D057865:Plant Immunity / Q000235:genetics / Q000502:physiology*; D040641:Quantitative Trait Loci / Q000235:genetics*; D014908:Triticum / Q000235:genetics / Q000378:metabolism* / Q000382:microbiology*