Cartographie génétique de Cichorium intybus L. : Marqueurs moléculaires et synténie

Belgium is the world's largest producer of industrial chicory. This species is cultivated to extract inulin, a storage polysaccharide with pre-biotic properties used in food processing. The selection of chicory varieties is mainly phenotypic and based essentially on sugar yield, bolting, disease resistance and root morphology. The objective of this work is to develop molecular tools that can improve and facilitate breeding. EST (Expressed Sequence Tag) libraries were used to develop SSR (Simple Sequence Repeats) and SNP (Single Nucleotide Polymorphism) genic markers. A total of 130 markers were validated for industrial chicory. These markers were used to build a genetic map of 1208 cM composed of 237 markers (152 AFLP markers, 27 SNP markers and 40 SSR markers) in collaboration with UCL and the Chicoline Company. The transcribed sequences associated with mapped genic markers were then used to search for orthologs in lettuce to develop a comparative map between the two species. This analysis has allowed identifying regions of synteny in which there were positional candidate genes potentially involved in different mechanisms of interest for the selection of chicory.