title: Genetic analysis of male fertility restoration in wild cytoplasmic male sterility G of beet.
abstract: Cytoplasmic male sterility (CMS) has been used in the breeding of sugar beet for decades but is also more generally an important feature of the reproductive system in its wild relative, Beta vulgaris ssp. maritima. Among the several CMSs found in wild populations, the G CMS is a mitochondrial variant of the respiratory chain. The segregants derived from a cross between a restored plant and a female (male-sterile) plant on G cytoplasm exhibited three sexual phenotypic classes: female, hermaphrodite and intermediate. The pattern of segregation suggests a genetic inheritance with two loci in epistatic interaction. Nevertheless, it was possible to apply a bulk segregant analysis approach to search for AFLP and microsatellite markers linked to the restorer locus ( RfG(1)) which controls the capacity to produce pollen [female versus non female (i.e. intermediates and hermaphrodites)] in the segregating population. A linkage group was constructed with four AFLP markers and nine microsatellites, and a total size of 40 cM (Kosambi). The closest marker, a microsatellite, was totally linked to RfG1, which was also flanked by two AFLP markers delimiting a 5 cM window. This linkage group was identified as being chromosome VIII where neither of the restorer loci of the Owen CMS are located.
authors.affiliation: Laboratoire de Génétique et Evolution des Populations Végétales, UMR-CNRS 8016, FR CNRS 1818, Université de Lille I, 59655 Villeneuve d'Ascq Cedex, France. Pascal.Touzet@univ-lille1.fr
authors.forename: Pascal
authors.initials: P
authors.lastname: Touzet
authors.forename: Nathalie
authors.initials: N
authors.lastname: Hueber
authors.forename: Alexandra
authors.initials: A
authors.lastname: Bürkholz
authors.forename: Stephen
authors.initials: S
authors.lastname: Barnes
authors.forename: Joël
authors.initials: J
authors.lastname: Cuguen
mesh_terms: D027461:Beta vulgaris / Q000235:genetics*; D002874:Chromosome Mapping; D003433:Crosses, Genetic; D005298:Fertility / Q000235:genetics; D005602:France; D017343:Genes, Plant / Q000235:genetics*; D018895:Microsatellite Repeats / Q000235:genetics; D010641:Phenotype; D011058:Pollen / Q000235:genetics / Q000254:growth & development*; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D013997:Time Factors