title: Alien introgression in the grasses Lolium perenne (perennial ryegrass) and Festuca pratensis (meadow fescue): the development of seven monosomic substitution lines and their molecular and cytological characterization.
abstract: OBJECTIVE
  To address the issues associated with food security, environmental change and bioenergy in the context of crop plants, the production, identification and evaluation of novel plant phenotypes is fundamental. One of the major routes to this end will be wide hybridization and introgression breeding. The transfer of chromosomes and chromosome segments between related species (chromosome engineering or alien introgression) also provides an important resource for determining the genetic control of target traits. However, the realization of the full potential of chromosome engineering has previously been hampered by the inability to identify and characterize interspecific introgressions accurately.
  
  
  METHODS
  Seven monosomic substitution lines have been generated comprising Festuca pratensis as the donor species and Lolium perenne as the recipient. Each of the seven lines has a different L. perenne chromosome replaced by the homoeologous F. pratensis chromosome (13 L. perenne + 1 F. pratensis chromosome). Molecular markers and genomic in situ hybridization (GISH) were used to assign the F. pratensis chromosomes introgressed in each of the monosomic substitutions to a specific linkage group. Cytological observations were also carried out on metaphase I of meiosis in each of the substitution lines.
  
  
  RESULTS
  A significant level of synteny was found at the macro-level between L. perenne and F. pratensis. The observations at metaphase I revealed the presence of a low level of interspecific chromosomal translocations between these species.
  
  
  CONCLUSIONS
  The isolation of the seven monosomic substitution lines provides a resource for dissecting the genetic control of important traits and for gene isolation. Parallels between the L. perenne/F. pratensis system and the Pooideae cereals such as wheat, barley, rye, oats and the model grass Brachypodium distachyon present opportunities for a comparison across the species in terms of genotype and phenotype.
authors.affiliation: Institute of Biological, Environmental and Rural Sciences, Aberystwyth University, Gogerddan, Aberystwyth, Ceredigion, UK.
authors.forename: John
authors.initials: J
authors.lastname: Harper
authors.forename: Ian
authors.initials: I
authors.lastname: Armstead
authors.forename: Ann
authors.initials: A
authors.lastname: Thomas
authors.forename: Caron
authors.initials: C
authors.lastname: James
authors.forename: Dagmara
authors.initials: D
authors.lastname: Gasior
authors.forename: Maciej
authors.initials: M
authors.lastname: Bisaga
authors.forename: Luned
authors.initials: L
authors.lastname: Roberts
authors.forename: Ian
authors.initials: I
authors.lastname: King
authors.forename: Julie
authors.initials: J
authors.lastname: King
mesh_terms: D023902:Chromosome Pairing / Q000235:genetics; D032461:Chromosomes, Plant / Q000235:genetics; D031751:Festuca / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D005819:Genetic Markers / Q000235:genetics; D014644:Genetic Variation; D018745:Genome, Plant / Q000235:genetics*; D005838:Genotype; D006824:Hybridization, Genetic / Q000235:genetics*; D007621:Karyotyping / Q000379:methods; D008129:Lolium / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D008540:Meiosis / Q000235:genetics; D030821:Plants, Genetically Modified
chemical_list: D005819:Genetic Markers