'Plant Breeding: Sustaining the Future' Abstracts of the XVIth EUCARPIA Congress, Edinburgh, Scotland, 10-14 September 2001 HIGH PRECISION INTERSPECIES TRANSFER OF RESTORER GENES K.E. BETT, D.J. LYDIATES Agriculture & Agri-Food Canada, Saskatoon Research Centre, 107 Science Pl, Saskatoon, SK S7N 0X2, Canada

Raphanus represents a valuable source of genetic variation that can be used in Brassica breeding.  Several attempts have been made to transfer genes controlling different traits, however this intergenomic transfer has been complicated by the inheritance of large segments of Raphanus chromosomes.  Genes can be transferred more precisely from one species to the other by using markers to identify crossovers either side of the gene of interest.  Brassica RFLP clones were used to generate a genome-wide map of Raphanus and three CMS restorer loci were identified and mapped.  Comparative mapping between Raphanus and Brassica was carried out and markers were used to follow the Raphanus chromosomes through several generations of interspecies crossing.  Markers are currently being used to identify products of intergenomic recombination events close to the restorer genes.