title: Molecular identification of a new powdery mildew resistance gene Pm41 on chromosome 3BL derived from wild emmer (Triticum turgidum var. dicoccoides).
abstract: Powdery mildew caused by Blumeria graminis f. sp. tritici is an important wheat disease in China and other parts of the world. Wild emmer (Triticum turgidum var. dicoccoides) is the immediate progenitor of cultivated tetraploid and hexaploid wheats and thus an important resource for wheat improvement. Wild emmer accession IW2 collected from Mount Hermon, Israel, is highly resistant to powdery mildew at the seedling and adult plant stages. Genetic analysis using an F(2) segregating population and F(2:3) families, derived from a cross between susceptible durum cultivar Langdon and wild emmer accession IW2, indicated that a single dominant gene was responsible for the resistance of IW2. Bulked segregant and molecular marker analyses detected that six polymorphic SSR, one ISBP, and three EST-STS markers on chromosome 3BL bin 0.63-1.00 were linked to the resistance gene. Allelic variations of resistance-linked EST-STS marker BE489472 revealed that the allele was present only in wild emmer but absent in common wheat. Segregation distortion was observed for the powdery mildew resistance allele and its linked SSR markers with preferential transmission of Langdon alleles over IW2 alleles. The resistance gene was introgressed into common wheat by backcrossing and marker-assisted selection. Since no designated powdery mildew resistance gene has been found on chromosome 3BL, the resistance gene derived from wild emmer accession IW2 appears to be new one and was consequently designated Pm41.
authors.affiliation: State Key Laboratory for Agrobiotechnology, Ministry of Agriculture/Beijing Key Laboratory of Crop Genetic Improvement, Ministry of Education, China Agricultural University, Beijing 100193, People's Republic of China
authors.forename: Genqiao
authors.initials: G
authors.lastname: Li
authors.forename: Tilin
authors.initials: T
authors.lastname: Fang
authors.forename: Hongtao
authors.initials: H
authors.lastname: Zhang
authors.forename: Chaojie
authors.initials: C
authors.lastname: Xie
authors.forename: Hongjie
authors.initials: H
authors.lastname: Li
authors.forename: Tsomin
authors.initials: T
authors.lastname: Yang
authors.forename: Eviatar
authors.initials: E
authors.lastname: Nevo
authors.forename: Tzion
authors.initials: T
authors.lastname: Fahima
authors.forename: Qixin
authors.initials: Q
authors.lastname: Sun
authors.forename: Zhiyong
authors.initials: Z
authors.lastname: Liu
mesh_terms: D000483:Alleles; D001203:Ascomycota / Q000235:genetics*; D032461:Chromosomes, Plant; D003433:Crosses, Genetic; D020224:Expressed Sequence Tags; D017343:Genes, Plant; D005819:Genetic Markers; D014644:Genetic Variation; D006579:Heterozygote; D007113:Immunity, Innate; D018598:Minisatellite Repeats; D020161:Physical Chromosome Mapping; D010935:Plant Diseases / Q000235:genetics*; D012641:Selection, Genetic; D014908:Triticum / Q000235:genetics*
chemical_list: D005819:Genetic Markers