DEVELOPMENT OF A CONSENSUS LINKAGE RFLP MAP OF CULTIVATED SUNFLOWER (HELIANTHUS-ANNUUS L)

This paper provides the first description of a consensus map of the cu ltivated sunflower genome (Helianthus annuus L., n=17 chromosomes), ba sed on RFLP. A total of 180 probe-enzyme combinations were mapped on a t least one of five segregating progenies (three F-2 and two BC1 popul ations), revealing 237 loci that did not show any distortion of segreg ation. The consensus linkage map obtained with these loci covers 1150 cM and consists of 16 linkage groups of more than 20 cM, 7 groups of l ess than 20 cM and 18 unlinked loci. The mean distance between loci is 7 cM, but in some regions intervals of 20 cM remain. Genotypic and ga metic segregation distortions affect about 7% of loci. It was found th at 25% of the probes mapped using several different restriction enzyme s or that on different progenies they revealed 2 or more loci.