Identification of Molecular Markers for Marker-Assisted Selection of Malting Quality and Associated Traits in Barley

Abstract

Barley (Hordeum vulgare L.) is one of the most important cereal crops in North Dakota, which ranks second amongst all states for barley production in the United States. Barley is used for the production of malt, which is used for brewing beer. The malting and brewing industries set strict standards for malt quality; yet, determining malt quality of experimental barley lines is very expensive. For this reason, quality is typically determined at the latter stages of the breeding program, resulting in rejection of many genotypes after large investments for agronomic performance, disease resistance, and end-use quality evaluations have occurred. High quality malt cultivars must possess numerous genetically controlled characteristics. This limits the effectiveness of phenotypic selection for malt quality. The use of marker-assisted selection (MAS) may enable breeders to eliminate lines with undesirable traits earlier in the breeding process, reducing costs, and improving genetic gain. In spite of the large number of mapped QTLs, few examples exist in the literature in which QTL analysis and MAS have been applied to the genetic improvement of malting barley. This research was initiated to identify robust marker-trait associations for malting quality, disease resistance, and agronomic traits utilizing genome-wide association mapping of selected NDSU two-rowed lines. Our research successfully identified numerous marker-trait associations for the traits evaluated to be used for MAS to improve the North Dakota State University barley breeding program.