Reconstruction of the resistant haplotype for a 26 cM region of chromosome 13. (A) The reference genetic map for this region shows the order and distance between six SSR markers that map around the Ren1 locus. (B) At these markers the allele lengths (bp, bold) of the resistant haplotype, inferred from the two previously identified resistant accessions ‘Kishmish vatkana’ and ‘Karadzhandal’ are also identical to those of six of the resistant accessions identified in this study (Ren1 location in red). Three of these accessions, ‘Sochal’, ‘Vassarga tchernaia’ and ‘Late Vavilov’ are related to the two previously identified accessions, which strongly implies the powdery mildew resistance is derived from the similar ancestral lineage. (C) The allelic composition of the powdery mildew resistant accession ‘Chirai obak’ shows a recombination event between marker VMC3d12 and VVIh54, and (D) A recombination occurred between marker SC8-0071-014 and UDV124 for ‘Khalchili’. (E) ‘Matrassa’ shows patterns with double recombinations. (F) ‘DVIT3351.27’ has complex allelic pattern and may have different genetic background for powdery mildew resistance.