Association genetics in cultivated sunflower

Cultivated sunflower, Helianthus annuus, is an important oilseed, food, and ornamental crop grown throughout the world. Recently, major steps have been made toward generating genetic and genomic resources; however, the tools for associating phenotype with genotype have remained largely undeveloped. To help fill this gap, we have developed a permanent, publicly-available association mapping resource for sunflower. Association mapping, also known as linkage disequilibrium mapping, involves correlating molecular variation with phenotypic variation in a population consisting of a diverse assemblage of individuals (Pritchard et al. 2000). We grew the sunflower association panel, which consists of 288 diverse inbred lines, in replicate at three locations and phenotyped the population for a number of agronomically important traits. We genotyped the population with a 10K Illumina SNP array, and we are developing methods for high-throughput candidate gene selection. Here we describe the preliminary results from our association mapping project including phenotypic variation within the population, genotyping strategies, and findings of significant associations.