title: AER1, a major gene conferring resistance to Aphanomyces euteiches in Medicago truncatula.
abstract: Aphanomyces euteiches is a major soilborne oomycete pathogen that infects various legume species, including pea and alfalfa. The model legume Medicago truncatula has recently emerged as a valuable genetic system for understanding the genetic basis of resistance to A. euteiches in leguminous crops. The objective of this study was to identify genetic determinants of resistance to a broad host-range pea-infecting strain of A. euteiches in M. truncatula. Two M. truncatula segregating populations of 178 F(5) recombinant inbred lines and 200 F(3) families from the cross F83005.5 (susceptible) x DZA045.5 (resistant) were screened for resistance to A. euteiches. Phenotypic distributions observed suggested a dominant monogenic control of resistance. A major locus associated with resistance to A. euteiches, namely AER1, was mapped by bulk segregant analysis to a terminal end of chromosome 3 in M. truncatula and explained 88% of the phenotypic variation. AER1 was identified in a resistance-gene-rich region, where resistance gene analogs and genes associated with disease resistance phenotypes have been identified. Discovery of AER1 opens up new prospects for improving resistance to A. euteiches in cultivated legumes using a comparative genomics approach.
authors.affiliation: INRA, Agrocampus Ouest, Université Rennes I, UMR118, Amélioration des Plantes et Biotechnologies Végétales, Plant Genetics and Biotechnology, OUEST-genopole, Domaine de la Motte, BP35327, 35653 Le Rheu, France. Marie-Laure.Pilet@rennes.inra.fr
authors.forename: M-L
authors.initials: ML
authors.lastname: Pilet-Nayel
authors.forename: J-M
authors.initials: JM
authors.lastname: Prospéri
authors.forename: C
authors.initials: C
authors.lastname: Hamon
authors.forename: A
authors.initials: A
authors.lastname: Lesné
authors.forename: R
authors.initials: R
authors.lastname: Lecointe
authors.forename: I
authors.initials: I
authors.lastname: Le Goff
authors.forename: M
authors.initials: M
authors.lastname: Hervé
authors.forename: G
authors.initials: G
authors.lastname: Deniot
authors.forename: M
authors.initials: M
authors.lastname: Delalande
authors.forename: T
authors.initials: T
authors.lastname: Huguet
authors.forename: C
authors.initials: C
authors.lastname: Jacquet
authors.forename: A
authors.initials: A
authors.lastname: Baranger
mesh_terms: D044744:Aphanomyces / Q000502:physiology*; D002874:Chromosome Mapping; D032461:Chromosomes, Plant; D017343:Genes, Plant; D008040:Genetic Linkage; D020022:Genetic Predisposition to Disease; D023281:Genomics; D046913:Medicago truncatula / Q000235:genetics* / Q000382:microbiology*; D010935:Plant Diseases / Q000235:genetics* / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D010940:Plant Proteins