Physical Mapping in a Triplicated Genome: Mapping the Downy Mildew Resistance Locus Pp523 in Brassica oleracea L.

We describe the construction of a BAC contig and identification of a minimal tiling path that encompass the dominant and monogenically inherited downy mildew resistance locus Pp523 of Brassica oleracea L. The selection of BAC clones for construction of the physical map was carried out by screening gridded BAC libraries with DNA overgo probes derived from both genetically mapped DNA markers flanking the locus of interest and BAC-end sequences that align to Arabidopsis thaliana sequences within the previously identified syntenic region. The selected BAC clones consistently mapped to three different genomic regions of B.

Identification of pathogenesis-related ESTs in the crucifer downy mildew oomycete Hyaloperonospora parasitica by high-throughput differential display analysis of distinct phenotypic interactions with Brassica oleracea.

Crucifer downy mildew is caused by the obligatory biotrophic oomycete Hyaloperonospora parasitica (formerly Peronospora parasitica). So far, isolates infecting Arabidopsis thaliana have proven to be non-pathogenic on other crucifers and, despite its unequivocal merit as a research model, the pathosystem A. thaliana-H.