title: A set of Lotus japonicus Gifu x Lotus burttii recombinant inbred lines facilitates map-based cloning and QTL mapping.
abstract: Model legumes such as Lotus japonicus have contributed significantly to the understanding of symbiotic nitrogen fixation. This insight is mainly a result of forward genetic screens followed by map-based cloning to identify causal alleles. The L. japonicus ecotype 'Gifu' was used as a common parent for inter-accession crosses to produce F2 mapping populations either with other L. japonicus ecotypes, MG-20 and Funakura, or with the related species L. filicaulis. These populations have all been used for genetic studies but segregation distortion, suppression of recombination, low polymorphism levels, and poor viability have also been observed. More recently, the diploid species L. burttii has been identified as a fertile crossing partner of L. japonicus. To assess its qualities in genetic linkage analysis and to enable quantitative trait locus (QTL) mapping for a wider range of traits in Lotus species, we have generated and genotyped a set of 163 Gifu × L. burttii recombinant inbred lines (RILs). By direct comparisons of RIL and F2 population data, we show that L. burttii is a valid alternative to MG-20 as a Gifu mapping partner. In addition, we demonstrate the utility of the Gifu × L. burttii RILs in QTL mapping by identifying an Nfr1-linked QTL for Sinorhizobium fredii nodulation.
authors.affiliation: Centre for Carbohydrate Recognition and Signalling, Department of Molecular Biology and Genetics, Aarhus University, Denmark.
authors.forename: Niels
authors.initials: N
authors.lastname: Sandal
authors.forename: Haojie
authors.initials: H
authors.lastname: Jin
authors.forename: Dulce Nombre
authors.initials: DN
authors.lastname: Rodriguez-Navarro
authors.forename: Francisco
authors.initials: F
authors.lastname: Temprano
authors.forename: Cristina
authors.initials: C
authors.lastname: Cvitanich
authors.forename: Andreas
authors.initials: A
authors.lastname: Brachmann
authors.forename: Shusei
authors.initials: S
authors.lastname: Sato
authors.forename: Masayoshi
authors.initials: M
authors.lastname: Kawaguchi
authors.forename: Satoshi
authors.initials: S
authors.lastname: Tabata
authors.forename: Martin
authors.initials: M
authors.lastname: Parniske
authors.forename: Jose E
authors.initials: JE
authors.lastname: Ruiz-Sainz
authors.forename: Stig U
authors.initials: SU
authors.lastname: Andersen
authors.forename: Jens
authors.initials: J
authors.lastname: Stougaard
mesh_terms: D002874:Chromosome Mapping; D003433:Crosses, Genetic; D060146:Ecotype; D017343:Genes, Plant; D008040:Genetic Linkage; D005838:Genotype; D000070116:Lotus / Q000235:genetics*; D040641:Quantitative Trait Loci; D011995:Recombination, Genetic