title: Development of simple sequence repeat (SSR) markers and construction of an SSR-based linkage map in Italian ryegrass (Lolium multiflorum Lam.).
abstract: In order to develop simple sequence repeat (SSR) markers in Italian ryegrass, we constructed a genomic library enriched for (CA)n-containing SSR repeats. A total of 1,544 clones were sequenced, of which 1,044 (67.6%) contained SSR motifs, and 395 unique clones were chosen for primer design. Three hundred and fifty-seven of these clones amplified products of the expected size in both parents of a two-way pseudo-testcross F(1) mapping population, and 260 primer pairs detected genetic polymorphism in the F(1) population. Genetic loci detected by a total of 218 primer pairs were assigned to locations on seven linkage groups, representing the seven chromosomes of the haploid Italian ryegrass karyotype. The SSR markers covered 887.8 cM of the female map and 795.8 cM of the male map. The average distance between two flanking SSR markers was 3.2 cM. The SSR markers developed in this study will be useful in cultivar discrimination, linkage analysis, and marker-assisted selection of Italian ryegrass and closely related species.
authors.affiliation: Forage Crop Research Institute, Japan Grassland Agriculture and Forage Seed Association, 388-5 Higashiakada, Nasushiobara, Tochigi 329-2742, Japan. hirata@jfsass.or.jp
authors.forename: Mariko
authors.initials: M
authors.lastname: Hirata
authors.forename: Hongwei
authors.initials: H
authors.lastname: Cai
authors.forename: Maiko
authors.initials: M
authors.lastname: Inoue
authors.forename: Nana
authors.initials: N
authors.lastname: Yuyama
authors.forename: Yuichi
authors.initials: Y
authors.lastname: Miura
authors.forename: Toshinori
authors.initials: T
authors.lastname: Komatsu
authors.forename: Tadashi
authors.initials: T
authors.lastname: Takamizo
authors.forename: Masahiro
authors.initials: M
authors.lastname: Fujimori
mesh_terms: D001483:Base Sequence; D017931:DNA Primers; D008040:Genetic Linkage; D005819:Genetic Markers; D018745:Genome, Plant; D008129:Lolium / Q000235:genetics*; D011110:Polymorphism, Genetic; D012091:Repetitive Sequences, Nucleic Acid
chemical_list: D017931:DNA Primers; D005819:Genetic Markers