Marker assisted selection for sunflower rust resistance loci

Sunflower (Helianthus annuus L.) is an important international oilseed and confectionary crop. Severe rust infections can dramatically reduce the economic potential of the crop. In this study we report on the identification of molecular markers closely linked to several sunflower rust resistance loci. Robust genetic markers have been produced through the conversion of polymorphisms, identified using RAPD-PCR and bulk segregant analysis, into sequence characterised amplified regions (SCARs). Tight linkage has been estimated for all markers and their respective rust resistance loci. Confirmation of the accuracy and robustness of each marker has been achieved by scoring for the presence of the each marker in a range of sunflower germplasm and verification that the corresponding rust resistance locus is present by rust reaction analyses. The availability of these PCR based markers has enabled us to test all our germplasm for the presence of each tagged loci.