Genomic-wide association study for white spot resistance in a tropical maize germplasm

White spot is an important maize disease, prevalent in most high production tropical regions with a severe negative impact in grain yield. Breeding for white spot resistance is the most effective mechanism to control the disease. The objectives of this research include identifying and mapping chromosomal regions and putative genes associated to the maize response to white spot. We performed an association mapping with phenotypic data collected in two environments located at South region of Brazil, and by using a set of 355,972 high-quality single nucleotide polymorphism markers in a panel composed by 183 tropical field corn and popcorn inbred lines. Nine SNPs were significantly associated with white spot, five of them co-localized on previously reported quantitative trait loci regions, while remaining regions are novel. The total phenotypic variance explained (r 2 ) by the nine SNPs associated with white spot severity was 64.3%, while the variance explained by each SNP ranged from 0.72 to 25.54%. The identified putative gene models are promising candidates associated with white spot resistance. Once these SNPs were validated, they can be useful for selecting superior genotypes.