|PHAM, ANH-TUNG - University Of Georgia
|HARRIS, DONNA - University Of Georgia
|BUCK, JAMES - University Of Georgia
|SERRANO, JONATHAN - University Of Georgia
|ABDEL-HALEEM, HUSSEIN - University Of Georgia
|BOREMA, H - University Of Georgia
|LI, ZENGLU - University Of Georgia
Submitted to: PLOS ONE
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/7/2015
Publication Date: 5/19/2015
Publication URL: http://handle.nal.usda.gov/10113/61450
Citation: Pham, A., Harris, D., Buck, J., Serrano, J., Abdel-Haleem, H., Song, Q., Cregan, P.B., Borema, H.R., Li, Z. 2015. Fine mapping and characterization of candidate genes that control resistance to Cercospora Sojina K. Hara in two soybean germplasm accessions. PLoS One. DOI:10.1371/journal.pone.0126753.
Interpretive Summary: Frogeye Leaf Spot is a disease of soybean that is caused by the fungus Cercospora sojina. Frogeye Leaf Spot can cause yield loss to soybean growers in regions with a warm and humid climate. Two soybean lines from China were identified with resistance to Frogeye Leaf Spot. We used DNA markers for single nucleotide polymorphisms (SNPs) to map the resistance gene to a small, defined region on chromosome 13 and found that it is different than other known genes for resistance to Frogeye Leaf Spot. These markers can be used by plant breeders at universities, companies and private institutes who would like to develop new soybean varieties with resistance to Frogeye Leaf Spot.
Technical Abstract: In order to fine map the novel FLS resistance gene(s) in two PIs, PI 594891 and PI 594774, F2:3 seeds from the crosses Blackhawk (FLS susceptible genotype) ×PI 594891, and Blackhawk ×PI 594774 were genotyped with KASP markers that were designed based on the SoySNP 50k Infinium Chip data to identify recombinant events and locate candidate genes. Analysis of lines carrying key recombination events helped narrow the FLS-resistance QTL region in PI 594891 from 3.3 Mb to a 75kb region of the 'Williams 82' genome sequence with five annotated genes. The resistant gene in PI 594774 was fine-mapped into a 540 kb region that encompasses the 72 kb region found in PI 594891. Sequencing five candidate genes in PI 594891 identified three genes that have several mutations in the promoter, intron, 5', and 3' UTR regions. qPCR analysis showed a difference in expression levels of these genes in the PIs compared to Blackhawk in the presence of C. sojina. The mutant SNPs were used to develop KASP assays to detect the resistance alleles on chromosome 13 from the two PIs for marker-assisted selection.