Theoretical and Applied Genetics

, Volume 109, Issue 2, pp 294–304

Genetic linkage mapping of an annual × perennial ryegrass population


    • National ArboretumUSDA-ARS
  • R. E. Barker
    • National Forage Seed Production Research CenterUSDA-ARS
  • Geunhwa Jung
    • Department of Plant PathologyUniversity of Wisconsin
  • Sung-Chur Sim
    • Department of Plant PathologyUniversity of Wisconsin
  • M. A. Rouf Mian
    • The Noble Foundation
  • M. C. Saha
    • The Noble Foundation
  • L. A. Brilman
    • Seed Research of Oregon
  • M. P. Dupal
    • Amersham Biosciences Pty. Ltd.
  • J. W. Forster
    • Department of Primary Industries, Primary Industries Research Victoria, Plant Biotechnology CentreLa Trobe University
Original Paper

DOI: 10.1007/s00122-004-1647-3

Cite this article as:
Warnke, S.E., Barker, R.E., Jung, G. et al. Theor Appl Genet (2004) 109: 294. doi:10.1007/s00122-004-1647-3


Annual (Lolium multiflorum Lam.) and perennial (L. perenne L.) ryegrass are two common forage and turfgrass species grown throughout the world. Perennial ryegrass is most commonly used for turfgrass purposes, and contamination by annual ryegrass, through physical seed mixing or gene flow, can result in a significant reduction in turfgrass quality. Seed certifying agencies in the United States currently use a test called seedling root fluorescence (SRF) to detect contamination between these species. The SRF test, however, can be inaccurate and therefore, the development of additional markers for species separation is needed. Male and female molecular-marker linkage maps of an interspecific annual × perennial ryegrass mapping population were developed to determine the map location of the SRF character and to identify additional genomic regions useful for species separation. A total of 235 AFLP markers, 81 RAPD markers, 16 comparative grass RFLPs, 106 SSR markers, 2 isozyme loci and 2 morphological characteristics, 8-h flowering, and SRF were used to construct the maps. RFLP markers from oat and barley and SSR markers from tall fescue and other grasses allowed the linkage groups to be numbered, relative to the Triticeae and the International Lolium Genome Initative reference population P150/112. The three-generation population structure allowed both male and female maps to be constructed. The male and female maps each have seven linkage groups, but differ in map length with the male map being 537 cm long and the female map 712 cm long. Regions of skewed segregation were identified in both maps with linkage groups 1, 3, and 6 of the male map showing the highest percentage of skewed markers. The (SRF) character mapped to linkage group 1 in both the male and female maps, and the 8-h flowering character was also localized to this linkage group on the female map. In addition, the Sod-1 isozyme marker, which can separate annual and perennial ryegrasses, mapped to linkage group 7. These results indicate that Lolium linkage groups 1 and 7 may provide additional markers and candidate genes for use in ryegrass species separation.

Copyright information

© Springer-Verlag 2004