The Genetic Architecture of Southern Leaf Blight Resistance Revealed by Nested Association Mapping
Abstract
Southern leaf blight (SLB) is a fungal foliar pathogen of maize that occurs worldwide, but is more prevalent and destructive in warm temperate and tropical regions. Several SLB resistance QTL have been mapped at low resolution (~2 - 15 cM) in various genomic regions in several segregating populations. In order to fine-map the resistance genes and to elucidate the genetic architecture of this quantitative disease resistance, we evaluated the nested association mapping (NAM) population, developed as part of the NSF-funded Maize Diversity Project, for resistance to SLB. Exploiting advantages inherent in the NAM design, notably large population size, abundant marker data, and a broad sampling of maize germplasm, we hope to attain a high resolution, global QTL analysis of SLB resistance in maize