title: Fine mapping of RYMV3: a new resistance gene to Rice yellow mottle virus from Oryza glaberrima.
abstract: A new resistance gene against Rice yellow mottle virus was identified and mapped in a 15-kb interval. The best candidate is a CC-NBS-LRR gene. Rice yellow mottle virus (RYMV) disease is a serious constraint to the cultivation of rice in Africa and selection for resistance is considered to be the most effective management strategy. The aim of this study was to characterize the resistance of Tog5307, a highly resistant accession belonging to the African cultivated rice species (Oryza glaberrima), that has none of the previously identified resistance genes to RYMV. The specificity of Tog5307 resistance was analyzed using 18 RYMV isolates. While three of them were able to infect Tog5307 very rapidly, resistance against the others was effective despite infection events attributed to resistance-breakdown or incomplete penetrance of the resistance. Segregation of resistance in an interspecific backcross population derived from a cross between Tog5307 and the susceptible Oryza sativa variety IR64 showed that resistance is dominant and is controlled by a single gene, named RYMV3. RYMV3 was mapped in an approximately 15-kb interval in which two candidate genes, coding for a putative transmembrane protein and a CC-NBS-LRR domain-containing protein, were annotated. Sequencing revealed non-synonymous polymorphisms between Tog5307 and the O. glaberrima susceptible accession CG14 in both candidate genes. An additional resistant O. glaberrima accession, Tog5672, was found to have the Tog5307 genotype for the CC-NBS-LRR gene but not for the putative transmembrane protein gene. Analysis of the cosegregation of Tog5672 resistance with the RYMV3 locus suggests that RYMV3 is also involved in Tog5672 resistance, thereby supporting the CC-NBS-LRR gene as the best candidate for RYMV3.
authors.affiliation: Plant Diversity Adaptation and Development Research Unit, Institut de Recherche pour le Développement - Université de Montpellier, Montpellier, France.
authors.forename: Hélène
authors.initials: H
authors.lastname: Pidon
authors.affiliation: Plant Diversity Adaptation and Development Research Unit, Institut de Recherche pour le Développement - Université de Montpellier, Montpellier, France.
authors.forename: Alain
authors.initials: A
authors.lastname: Ghesquière
authors.affiliation: Plant Diversity Adaptation and Development Research Unit, Institut de Recherche pour le Développement - Université de Montpellier, Montpellier, France.
authors.forename: Sophie
authors.initials: S
authors.lastname: Chéron
authors.affiliation: Africa Rice Center, Cotonou, Benin.|FSAE, Université de Tillabéri, Tillabéri, Niger.
authors.forename: Souley
authors.initials: S
authors.lastname: Issaka
authors.affiliation: Interactions Plantes Microorganismes Environnement, Institut de Recherche pour le Développement - Centre de Coopération Internationale en Recherche Agronomique pour le Développement - Université de Montpellier, Montpellier, France.
authors.forename: Eugénie
authors.initials: E
authors.lastname: Hébrard
authors.affiliation: Plant Diversity Adaptation and Development Research Unit, Institut de Recherche pour le Développement - Université de Montpellier, Montpellier, France.
authors.forename: François
authors.initials: F
authors.lastname: Sabot
authors.affiliation: Plant Diversity Adaptation and Development Research Unit, Institut de Recherche pour le Développement - Université de Montpellier, Montpellier, France.|Africa Rice Center, Cotonou, Benin.|International Institute of Tropical Agriculture, Ibadan, Nigeria.
authors.forename: Olufisayo
authors.initials: O
authors.lastname: Kolade
authors.affiliation: Africa Rice Center, Cotonou, Benin.
authors.forename: Drissa
authors.initials: D
authors.lastname: Silué
authors.affiliation: Plant Diversity Adaptation and Development Research Unit, Institut de Recherche pour le Développement - Université de Montpellier, Montpellier, France. laurence.albar@ird.fr.
authors.forename: Laurence
authors.identifier: http://orcid.org/0000-0003-2832-1140
authors.initials: L
authors.lastname: Albar
mesh_terms: D002874:Chromosome Mapping; D060467:Disease Resistance / Q000235:genetics*; D017343:Genes, Plant; D005819:Genetic Markers; D012275:Oryza / Q000235:genetics*; D010641:Phenotype; D010935:Plant Diseases / Q000235:genetics* / Q000821:virology; D010942:Plant Viruses; D012328:RNA Viruses
chemical_list: D005819:Genetic Markers
keywords: Fine mapping; NB-LRR; Oryza glaberrima; RYMV; Resistance; Rice