PCR Conditions for the Detection of Molecular Markers Associated with Blackleg (Leptosphaeria spp.) Resistance in Rapeseed (Brassica napus L.)

Blackleg disease, caused by Leptosphaeria spp. fungi, is a major contributor to significant global yield losses in Brassica napus. Thus, selecting resistant plants using molecular markers linked to resistance loci is a common mitigation strategy. The latter, however, faces a challenge as pathogen virulence can overcome host resistance. This necessitates the identification of superior resistant genotypes through the use of numerous novel molecular markers and simplified detection methods to accelerate breeding programs. Based on our previous work, this study evaluated and verified molecular markers linked to blackleg disease resistance. A crucial finding is the identification of polymorphisms within SilicoDArT-type marker sequences that directly confer resistance. We also provide primer sequences for conventional PCR-based detection of SNP-type and SilicoDArT-type markers and a modified PCR protocol to enhance SNP detection efficiency. These validated markers and optimized PCR conditions are expected to significantly aid plant breeders in developing new, more resistant rapeseed varieties.