Identification of Novel Barley Alleles Impacting Malt Quality Traits

Malting quality has been one of the primary focuses in barley (Hordeum vulgare L.) breeding programs but has been difficult for breeders to manipulate due to the quantitative nature of the traits involved. To assist in breeding for malt quality traits, identifying and locating genomic regions that impact these traits is essential. Two populations were used to conduct genome-wide association studies in order to elucidate the alleles responsible for variation in key malting traits. The first population, composed of 332 lines genotyped with 3,072 SNP markers, represented the germplasm of the Montana State University barley breeding program, including feed, food, and malt lines. The second population, with 650 lines genotyped with 384 SNPs, consisted of eleven bi-parental families whose parents were lines developed strictly for malting purposes. All lines were phenotyped at the USDA-ARS Cereal Crops Research Unit in Madison, Wisconsin. Mixed linear models were applied to the data using a Q+K approach in order to find single marker-trait associations. The R package "GAPIT" (Lipka et al 2012) was used with the implementation of FDR p-values to identify significant associations. The result of this work gives a comprehensive overview of the salient regions of the barley genome impacting malting traits. These beneficial alleles will prove useful for development of superior malting cultivars for the Montana barley production region.