Description: Powdery mildew (PMD), caused by the Microsphaera diffusa pathogen, would result in substantial yield decreases of susceptible soybean under favorable environmental conditions. Soybean PMD damage could be effectively prevented by identifying resistance genes and developing resistant cultivars. In this study, 331 soybean germplasm accessions, mainly from Northeast China, underwent genotyping using the SoySNP50K BeadChip, and was evaluated for resistance to PMD in greenhouse. Genome-wide association studies utilizing the factored spectrally transformed linear mixed models, mixed linear model, efficient mixed-model association eXpedited and compressed mixed linear model were conducted to identify marker-trait associations while effectively controlling for population structure. The results demonstrated that seven SNP loci were found strongly associated with PMD resistance in soybean. Of these, one SNP localized to chromosome (Chr) 14 and six SNP with low linkage disequilibrium value localized Chr16 near or in the region of previously mapped genes. A total of 95 genes, including 17 resistance (R)-like genes as potential candidate genes were found within the candidate region in the reference genome of Williams82. In addition, quantitative real-time reverse transcription polymerase chain reaction analysis evaluated the genes expression levels between highly resistant and susceptible genotypes, focusing on the leaf tissues taken in at different times after M. diffusa inoculation. Among the examined genes, three R-like genes Glyma.16G210800, Glyma.16G212300 and Glyma.16G213900, were identified as strong candidates associated with PMD resistance. The identification of three R-like candidate genes enhances our knowledge of soybean resistance to PMD. Furthermore, those significant SNPs strongly associated with resistance can be used to develop SNP markers for genetic improvement in breeding resistant M. diffusa soybean cultivars.

Data type: Phenotype or Genotype

Sample scope: Other

Release date: 2023-10-21

Last updated: 2023-08-01