The use of bulk segregant analysis to identify a RAPD marker linked to the Mla locus of barley

Resistance to powdery mildew, Blumeria graminis f.sp. hordei, is a major goal of many barley breeding programs. Resistance conferred by genes located at Mla locus is commonly used by barley breeders for effective control of powdery mildew. The use of molecular markers may facilitate barley breeding for powdery mildew resistance. In this study, bulked segregant analysis (BSA) was used to determine random amplified polymorphic DNAs (RAPDs) markers linked to Mla locus. Thirty one homozygous (17 resistant and 14 susceptible) F3 families from a cross between variety Pallas and single plant line E 1059-1-1 carrying gene at Mla locus were used as plant material. A total of 385 random 10-mer primers were screened to identify polymorphism between the appropriate resistant and susceptible DNA bulks and parents in BSA analysis. Only one PCR marker OPAA3400 (primer sequence: 5’-TTAGCGCCCC-3’), amplified in polymerase chain reaction (PCR) proved close linkage and was positioned in distance of 10 cM from Mla locus with 5.0 LOD threshold.