1a. Objectives (from AD-416):
Identify NSGC accessions with enhanced nitrogen and water use efficiency (NUE, WUE) and determine the genetic basis of the traits using association mapping.
1b. Approach (from AD-416):
Single-plant selections from the NSGC barley and wheat core collections will be grouped by maturity and screened in the field under varying nitrogen and water levels using an augmented experimental design. Canopy spectral radiometry and yield will be used to measure NUE and WUE. Experiments will be conducted over 5 cropping seasons. SNP data will be generated for the accessions as part of the Triticeae CAP project and data will be used to explore the genetic basis of enhanced NUE and WUE within the accessions.
3. Progress Report:
To assess drought and nitrogen use efficiency, over 500 six-row spring barley accessions from the National Small Grains Collection core subset and five checks varieties were planted in an augmented complete block design in a drip irrigation nursery at Aberdeen, Idaho. The design was replicated under three water/nitrogen (N) treatments: normal water and normal N, terminal drought and normal N, terminal drought and low N. Data were gathered and are being analyzed. The 540 spring wheat NSGC accessions evaluated in 2011 were retested to obtain a more precise evaluation of the phenotypes and to test the reproducibility of the WUE results across years. The 540 wheat lines are being tested under two treatments: normal water and terminal drought (both with normal N). All wheat and barley accessions are being evaluated for water and N use efficiency (WUE and NUE) using Canopy Spectral Reflectance (CSR) equipment, a sophisticated measure of water and N status. Over 600 winter wheat accessions were planted in a rain-fed environment in Rockland, Idaho, for a preliminary evaluation of yield and agronomic performance and for a seed increase for the 2013 evaluation. A total of 256 elite spring wheat lines were planted under limited water conditions in Aberdeen and will be evaluated for yield and WUE. Of the 540 spring wheat accessions evaluated in 2011, thirty were selected and used in crossing in several breeding programs in the U.S. A set of 123 hard white spring wheat accessions has been used in an association analysis to identify the location within the wheat genome of important traits such as late maturity alpha amylase, a quality defect that is widespread in hard spring wheat varieties in the western USA. Three chromosome regions were identified. This set of materials has also been used in association mapping for fusarium head blight and baking quality. The results of this project relate to Objective 2 of the parent project, “Strategically evaluate small grains genetic resources for priority biotic and abiotic stress resistance.”