'Plant Breeding: Sustaining the Future' Abstracts of the XVIth EUCARPIA Congress, Edinburgh, Scotland, 10-14 September 2001   MOLECULAR MARKER ANALYSIS OF INTROGRESSION IN TRIFOLIUM HYBRIDS M.T. ABBERTON, A.H. MARSHALL, T. MICHEALSON-YEATES, C. WHITE Legume Breeding Group, Institute of Grassland and Environment Research, Plas Gogerddan, Aberystwyth, SY23 3EB, Wales

Trifolium repens (white clover) is a forage legume of key importance in the development of more sustainable livestock farming. However, its seeds yield under UK conditions is unreliable and it shows only moderate drought tolerance. There is limited variation for both these traits within the white clover gene pool. At IGER introgression of the profuse flowering of Trifolium nigrescens and the rhizomatous habit of Trifolium ambiguum into white clover has been carried out successfully. We are using a bulk segregant AFLP approach on a range of backcross families for each hybrid. This has identified markers occurring only in high seed set plants or in plant with rhizomes, depending on the hybrid. These associations are now being confirmed on individual plants.