Genetic analysis of powdery mildew resistance in German winter wheat cultivar Cortez

P>Fungal diseases of wheat, including powdery mildew (Pm), have caused significant crop, yield and quality losses throughout the world and continue to impact on production. Knowledge of the genetic basis of powdery mildew resistance of wheat cultivars will greatly support future efforts developing and cultivating resistant cultivars. Genetic studies were conducted on the German winter wheat cultivar 'Cortez' to identify genes involved in powdery mildew resistance at seedling and adult plant growth stages using doubled haploid (DH) population Atlantis/Cortez. Analysis of association between molecular markers and powdery mildew severity in selected genotypes indicated the involvement of two genes on chromosomes 1A and 7B in seedling resistance. The same gene on chromosome 1A was also found to be effective at adult plant stage. Quantitative trait loci analysis corroborated that the gene on chromosome 1A significantly contributed to field resistance in all five test environments and explained between 22.9% and 51.4% of the total phenotypic variation. The gene on chromosome 7B was identified as Pm5, whereas the gene on chromosome 1A potentially conditioning resistance was identified as Pm3e.