title: Molecular identification of a new powdery mildew resistance gene on chromosome 2BS from Triticum turgidum ssp. dicoccum.
abstract: Powdery mildew caused by the fungal pathogen Blumeria graminis f. sp. tritici (Bgt), is a destructive foliar disease on wheat in many regions of the world. Triticum turgidum ssp. dicoccum (2n=4x=28) shows particular promises as a donor source of useful genetic variation for several traits, including disease resistances that could be introgressed to cultivated wheats. Accession MG5323, resistant to powdery mildew, was crossed to the susceptible durum cultivar Latino and a set of 122 recombinant inbred lines (RILs) was produced. F₁ and F₂ progenies and the RIL population were tested with one isolate of Blumeria graminis and data obtained indicated that a single dominant gene, temporarily designated Ml5323, controlled resistance at the seedling stage. Molecular markers were used to characterize and map the powdery mildew resistance gene. Twelve microsatellite markers were linked to the resistance gene, and among them, EST-SSR CA695634 was tightly linked to the resistance gene, which was assigned to chromosome arm 2BS and physically mapped to the gene rich region of fragment length (FL) 0.84-1.00. An allelism test showed that the Ml5323 gene and the resistant gene Pm26 of ssp. dicoccoides localized in the same bin, are not allelic and tightly linked.
authors.affiliation: Department of Environmental and Agro-Forestry Biology and Chemistry, University of Bari, Aldo Moro, Via Amendola 165/A, 70126 Bari, Italy.
authors.forename: Luciana
authors.initials: L
authors.lastname: Piarulli
authors.forename: Agata
authors.initials: A
authors.lastname: Gadaleta
authors.forename: Giacomo
authors.initials: G
authors.lastname: Mangini
authors.forename: Massimo Antonio
authors.initials: MA
authors.lastname: Signorile
authors.forename: Marina
authors.initials: M
authors.lastname: Pasquini
authors.forename: Antonio
authors.initials: A
authors.lastname: Blanco
authors.forename: Rosanna
authors.initials: R
authors.lastname: Simeone
mesh_terms: D001203:Ascomycota / Q000502:physiology; D002874:Chromosome Mapping; D032461:Chromosomes, Plant / Q000235:genetics*; D003433:Crosses, Genetic; D060467:Disease Resistance / Q000235:genetics; D005799:Genes, Dominant; D017343:Genes, Plant / Q000235:genetics*; D008040:Genetic Linkage; D054884:Host-Pathogen Interactions; D018895:Microsatellite Repeats / Q000235:genetics; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D036226:Seedlings / Q000235:genetics / Q000382:microbiology; D014908:Triticum / Q000235:genetics* / Q000382:microbiology