Documenting Nutrient Accumulation Rates in Four Barley Varieties

The proposed study will be conducted at the Aberdeen Research and Extension Center in Aberdeen, ID during the 2015 and 2016 growing seasons. Little work has investigated nitrogen or other nutrient accumulation in barley, particularly in the various classes (i.e., malt, feed, and food). The proposed study would seek to fill this gap and provide detailed information for growers and researchers.

Four barley varieties will be used consisting of two malt, one food, and one feed class. Malt barley specifications include grain protein levels of <13.0% to meet malting specifications, while higher grain protein levels can be achieved, they are not desirable for malting. In Idaho small grain trials over 12 site years, the average grain protein of malt barley varieties was 11.5%. In contrast, food barley is an emerging market where varieties are being bred for high β-glucan levels, due to potential health benefits, at the USDA-ARS Aberdeen Research and Extension Center where these varieties can exceed 18.0% in grain protein. Average protein was 15.3% in Idaho small grain trials over 12 site years. Finally, feed barley, a traditional sector of the market, which has decreased greatly due to changes in feed rations in the animal production sector, have grain protein levels similar to malt varieties at approximately 11%.

The research will be a randomized complete block with four replications (n=16) of two common malt varieties (i.e., AB-Voyager and Moravian 69, AB-InBev and MillerCoors, respectively), one food variety developed at the USDA-ARS Small Grains Research Center, Aberdeen, ID (i.e., Transit), and one feed variety (i.e., Champion) developed by WestBred LLC. will be compared in terms of nitrogen accumulation and partitioning and final grain yield and percent nitrogen/protein. Fertilizer N will be applied based on current University of Idaho Extension recommendations and other nutrients applied based on soil tests to ensure no deficiencies occur. Six plant samples will be collected from 3-ft row sections at Feekes 4-5 (pseudostem erection), Feekes 6-7 (jointing), Feekes 8-9 (flag leaf emergence), Feekes 10.1 (heading), Feekes 11.1-11.2 (dough development), and at Feekes 11.4 (maturity) where the final two samplings will be separated into stems and heads and analyzed separately to determine partitioning. Plants will be dried to a constant weight, mass determined and nitrogen determined on an elemental analyzer. Paired-adjacent plots will be setup where one plot will be sacrificed for tissue sampling and the other retained for final grain yield. Final results will be compared using an ANOVA.

Currently the project is focused on nitrogen accumulation and partitioning, but we would be interested in adding other nutrients either on a specific subset or on all samples pending funding availability.