Simple sequence repeats (SSR) polymorphism of 34 microsatellite loci (LG1 8 and 13) was studied in lines carrying the downy mildew resistance genes Pl and lines with no Pl . The microsatellite loci ORS328 and ORS781 were selected as markers for genes Pl6 and Pl8 in lines HA 335 and QHP-1 respectively. Markers were identified for gene Pl ARG in RHA 419 and some accessions of H. argophyllus . The SSR markers ORS509 ORS605 ORS610 ORS1182 and ORS1039 were proven to reliably identify the parental line carrying Pl ARG gene control and select the heterozygous F 1 hybrids and identify homozygous genotypes in F 2 generations. Obtained results indicate the necessity of validation of the markers in various germplasm pools and breeding collections. The SSR markers that are tightly linked to Pl 6 Pl 8 Pl ARG would be useful in the sunflower breeding. Pl ARG homozygous F 2 segregants developed and identified with marker assisted selection in this study are recommended for further breeding as a new source of genetically determined resistance to downy mildew.