Harnessing Genomic Variability to Reduce Stalk Lodging in Maize.

Stalk lodging is defined as the breakage of a corn stalk below the ear. Every year, the maize industry is faced with yield loss due to stalk lodging. The abundance of new genomic information available has increased the ability of computational tools to study the genetic basis of agricultural traits. This project will use statistical approaches to rigorously quantify the genomic underpinnings of stalk lodging in maize using publicly available data sets. The overall goal of this project is to study the relationship between genotype and phenotype in maize with respect to lodging. A genome-wide association study (GWAS) will be conducted using the unified mixed linear model. Depending on the underlying genetic architecture of lodging and marker density, it is possible that this GWAS will detect moderate- to large- effect loci that are associated with lodging tolerance. The same set of markers will also be used to create genomic selection models, which will enable an assessment of the ability to breed for lodging tolerance in maize based on marker information alone. The predictive ability of these models will be assessed through k-fold cross validation; the actual number of folds used will be determined after a data set is identified. The results from this study will underscore breeding efforts for lodging tolerance in maize by determining if substantial reductions in breeding cycle time can be realized through the utilization of genomic markers.