Association genetics in crop improvement

Increased availability of high throughput genotyping technology together with advances in DNA sequencing and in the development of statistical methodology appropriate for genome-wide association scan mapping in presence of considerable population structure contributed to the increased interest association mapping in plants. While most published studies in crop species are candidate gene-based, genome-wide studies are on the increase. New types of populations providing for increased resolution and power of detection of modest-size effects and for the analysis of epistatic interactions have been developed. Classical biparental mapping remains the method of choice for mapping the effects of alleles rare in germplasm collections, such as some disease resistance genes or alleles introgressed from exotic germplasm.