Location: Grain Quality and Structure Research
Project Number: 3020-43440-001-000-D
Project Type: In-House Appropriated
Start Date: Jun 30, 2015
End Date: Apr 12, 2020
Objective 1: Integrate commercial grain sorghum quality traits with the timing and duration of heat and/or drought stress during grain fill. • Sub-Objective 1.A. Determine how timing of drought stress during grain fill impacts protein and starch chemistry and digestibility. • Sub-Objective 1.B. Determine the degree to which heat stress impacts sorghum grain quality traits. Objective 2: Enable new rapid/high-throughput commercial methods to measure grain sorghum composition and quality traits. • Sub-Objective 2.A. Develop an in-vitro cellular antioxidant activity assay for measuring the efficacy of sorghum bioactive compounds in response to radical oxidative species. • Sub-Objective 2.B. Determine the effectiveness of a blood glucometer in determining fermentation efficiency using sorghum grain. Objective 3: Integrate the stability/variability of grain sorghum compositional quality and bionutrient components across multiple commercial production environments. • Sub-Objective 3.A. Evaluate the variability in sorghum grain composition related to protein and starch across multiple growing environments. • Sub-Objective 3.B. Characterize phytonutrient composition in tannin and black sorghum germplasm grown at multiple locations. Objective 4: Molecular biological technologies will employ gene flow analysis to identify sorghum compositional and quality traits variants migrating through field/commercial sorghum breeding programs.
Sorghum [Sorghum bicolor (L.) Moench] is an important drought tolerant crop in regions of the Great Plains where water is limited and rainfall unpredictable. Sorghum has been primarily used for animal feed in the U.S. but recently has seen increasing use in the food and biofuel industries which has provided a new growth area for sorghum utilization. That said, there has not been extensive research conducted on grain quality factors related to sorghum. Recent advances have been made regarding improving sorghum protein and starch digestibility at the genetic level, yet little is known about how environmental factors impact sorghum grain quality attributes and nutritional bioavailability. Sorghum is typically grown under non-irrigated conditions and can face serious drought and heat stress during grain fill. Drought and heat stress may become more prevalent in sorghum growing regions due to climate change and have the potential to severely impact sorghum grain composition and end-use quality traits. Consistency is an important quality attribute of cereal crops and further research is required to quantify the degree to which sorghum grain quality is impacted by the environment. Our research will support on-going efforts to improve sorghum grain quality at the genetic level by providing grain quality information to breeding programs about the stability of various traits. We will provide knowledge of how drought and heat stress impacts sorghum grain quality, ultimately providing information necessary for the sorghum breeding community to improve the end-use quality of sorghum.