title: An enhanced molecular marker based genetic map of perennial ryegrass (Lolium perenne) reveals comparative relationships with other Poaceae genomes.
abstract: A molecular-marker linkage map has been constructed for perennial ryegrass (Lolium perenne L.) using a one-way pseudo-testcross population based on the mating of a multiple heterozygous individual with a doubled haploid genotype. RFLP, AFLP, isoenzyme, and EST data from four collaborating laboratories within the International Lolium Genome Initiative were combined to produce an integrated genetic map containing 240 loci covering 811 cM on seven linkage groups. The map contained 124 codominant markers, of which 109 were heterologous anchor RFLP probes from wheat, barley, oat, and rice, allowing comparative relationships between perennial ryegrass and other Poaceae species to be inferred. The genetic maps of perennial ryegrass and the Triticeae cereals are highly conserved in terms of synteny and colinearity. This observation was supported by the general agreement of the syntenic relationships between perennial ryegrass, oat, and rice and those between the Triticeae and these species. A lower level of synteny and colinearity was observed between perennial ryegrass and oat compared with the Triticeae, despite the closer taxonomic affinity between these species. It is proposed that the linkage groups of perennial ryegrass be numbered in accordance with these syntenic relationships, to correspond to the homoeologous groups of the Triticeae cereals.
authors.affiliation: Plant Biotechnology Centre, Agriculture Victoria, Department of Natural Resources and Environment, La Trobe University, Bundoora, Australia.
authors.forename: Elizabeth S
authors.initials: ES
authors.lastname: Jones
authors.forename: Natalia L
authors.initials: NL
authors.lastname: Mahoney
authors.forename: Michael D
authors.initials: MD
authors.lastname: Hayward
authors.forename: Ian P
authors.initials: IP
authors.lastname: Armstead
authors.forename: J Gilbert
authors.initials: JG
authors.lastname: Jones
authors.forename: Mervyn O
authors.initials: MO
authors.lastname: Humphreys
authors.forename: Ian P
authors.initials: IP
authors.lastname: King
authors.forename: Tsugutoshi
authors.initials: T
authors.lastname: Kishida
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Yamada
authors.forename: François
authors.initials: F
authors.lastname: Balfourier
authors.forename: Gilles
authors.initials: G
authors.lastname: Charmet
authors.forename: John W
authors.initials: JW
authors.lastname: Forster
mesh_terms: D002874:Chromosome Mapping; D003433:Crosses, Genetic; D018744:DNA, Plant / Q000235:genetics* / Q000302:isolation & purification; D020224:Expressed Sequence Tags; D008040:Genetic Linkage; D005819:Genetic Markers; D018745:Genome, Plant; D005838:Genotype; D006238:Haploidy; D006579:Heterozygote; D007527:Isoenzymes / Q000235:genetics; D008129:Lolium / Q000201:enzymology / Q000235:genetics*; D006109:Poaceae / Q000235:genetics*; D012150:Polymorphism, Restriction Fragment Length; D012091:Repetitive Sequences, Nucleic Acid; D013045:Species Specificity; D026801:Synteny
chemical_list: D018744:DNA, Plant; D005819:Genetic Markers; D007527:Isoenzymes