(Montana State University - Bozeman, College of Agriculture, 2007) Jewell, Jeremy Burke; Chairperson, Graduate Committee: Tom Blake.
Recent research has identified important characteristics of barley grain as feed for cattle. Of these, low ruminal dry-matter digestibility (DMD) is of particular importance as it is highly correlated with animal performance and with animal health. This research attempts to identify genetic loci that contribute to the ruminal DMD of barley grain. The utility of the barley ant18 mutation for decreasing ruminal DMD was investigated. The DMD of several barley cultivars and their ant18 mutations was investigated in a randomized complete block design in two environments. Genotype by environment interaction was present: in the greenhouse the DMD of ant18 mutants was less than that of the wildtype, and in a dryland field the reverse was true. Because of this interaction, ant18 is not likely to be a reliable method of modulating DMD. With the aim of identifying markers for marker-assisted selection (MAS), a 123-member inbred population was developed from a cross of Haxby and PI 28624. PI 28624 is a low DMD accession from the USDA barley collection.
