ARS | Publication request: Using NIRS to Predict Fiber and Nutrient Content of Dryland Cereal Cultivars

Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 12, 2009
Publication Date: December 4, 2009
Repository URL: http://hdl.handle.net/10113/43133
Citation: Stubbs, T.L., Kennedy, A.C., Fortuna, A. 2009. Using NIRS to Predict Fiber and Nutrient Content of Dryland Cereal Cultivars. Journal of Agricultural and Food Chemistry. DOI:10.1021/jf9025844

Interpretive Summary: Cropping systems in the dryland farming regions of the Pacific Northwest are dominated by winter and spring wheat, and spring barley. Cultivars of each crop type that do not rapidly decompose have hindered the implementation of conservation farming systems and reduced-till and no-till seeding. Growers have observed differences in straw decomposition among the cultivars that are currently produced; however, little information exists on the straw characteristics that affect straw decomposition. Additional knowledge on cereal straw decomposition will allow growers to design crop rotations that promote the adaptation of reduced-till and no-till seeding. ARS scientists in Pullman, Washington, in collaboration with Washington State University scientists, have identified the fiber and nutrient composition of spring wheat, winter wheat and spring barley straw and are better able to predict straw decomposition among different crop cultivars grown under diverse conditions. Information on differences in straw decomposition among wheat and barley cultivars will assist growers in selecting cultivars for reduced systems.

Technical Abstract: Residue from cultivars of spring wheat (Triticum aestivum L.), winter wheat and spring barley (Hordeum vulgare L.) was characterized for fiber and nutrient traits using reference methods and near infrared spectroscopy (NIRS). Calibration models were developed for neutral detergent fiber (NDF); acid detergent fiber (ADF); acid detergent lignin (ADL); carbon (C) ; sulfur (S); nitrogen (N); and C:N. When calibrations were tested against validation sets for each crop year, NIRS was an acceptable method for predicting NDF (standard error of prediction (SEP) < 0.87; R2 > 0.90) and ADF (SEP < 0.81; R2 > 0.92), and moderately successful for ADL in one year of the study (SEP = 0.44; R2 = 0.81), but less successful for C, S, N and C:N (R2 all < 0.57). These results indicate that NIRS can predict NDF and ADF of cereal residue from dryland cropping systems, and is a useful tool to estimate residue decomposition potential.