2007 Annual Report 1a.Objectives (from AD-416) To contribute to the improvement of oat quality by characterizing panicle and kernel structure characteristics associated with environmental stability of high test weight, by determining kernel structure characteristics associated with improved milling yield, and by the characterization of genotypic and environmental effects on the chemical composition of polar lipids in oat groats. 1b.Approach (from AD-416) In order to determine panicle and kernel structure effects on environmental stability of test weight, fifty advanced lines of oats will be selected from an oat breeding program in North Dakota. Selected lines will have high potential for high test weight and will be highly variable for panicle size. Lines will be grown in four diverse environments and intact panicles will be harvested. Panicle and kernel size and structure will be analyzed along with test weight to determine physical characteristics that provide high test weight even in harsh environments that adversely affect yield. Kernel structure associated with improved milling yield will be determined by dehulling different genotypes of oats with an impact dehuller, similar to dehullers used by industry. Every oats sample will be fractionated by kernel size by three different mechanisms that divide according to different size characteristics. Slotted sieves will separate according to kernel width, disc separators will separate according to kernel length, and a gravity table will separate according to kernel density. Each size fraction will be dehulled at a series of dehuller rotor speeds, so that the influence of different kernel size characteristics on dehulling efficiency and milling yield can be determined. Finally, oat polar lipids will be characterized from a variety of oat cultivars grown in diverse environments. Polar oat lipids will be extracted and analyzed for their chemical composition by chloroform/methanol/water extraction, separation by silica gel chromatography, and analyzed by high pressure liquid chromatography using an evaporative light scattering detector. 4.Accomplishments Physical Basis for Test Weight in Oats: Value of oats is largely dependent on their bulk density or test weight, which is the mass of grain that fits into a specified volume container, yet virtually nothing is known of the physical basis for variation in oat test weight. We have developed a unique sand displacement method to measure oat kernel volume, which has allowed us to determine oat kernel envelope volume, kernel packing efficiency, oat density, hull density, and the contribution of these factors to test weight. This information allows us to determine the physical basis for any variation observed in test weight and allows us to understand mechanisms of how genetic and environmental factors affect test weight and oat grain value. This accomplishment aligns with NP306 Component 1: Quality Characterization, Preservation, and Enhancement. 5.Significant Activities that Support Special Target Populations Oats are more commonly grown by smaller farms. This project contributes to the development and release of new oat cultivars through the North Dakota State University Oat Improvement Program. We have been particularly active in the selection of high fiber cultivars, such as “HiFi”, which provide greater health benefits to consumers and more value to the producers. 6.Technology Transfer Number of non-peer reviewed presentations and proceedings 1 Review Publications Doehlert, D.C., Wiessenborn, D.P. 2007. Influence of physical grain characteristics on optimal rotor speed during impact dehulling of oats. Cereal Chemistry. 84:294-300.