Author
STUBBS, TAMI - WASHINGTON STATE UNIV | |
Kennedy, Ann | |
REISENAUER, PATRICK - WASHINGTON STATE UNIV | |
BURNS, JOHN - WASHINGTON STATE UNIV |
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 2/12/2009 Publication Date: 2/12/2009 Citation: Stubbs, T.L., Kennedy, A.C., Reisenauer, P.E., Burns, J. 2009. Chemical Composition of Residue from Cereal Crops and Cultivars in Dryland Ecosystems. Agronomy Journal. 101:538-545. 2009 Interpretive Summary: Cropping systems in the dryland farming region of eastern Washington state 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 no-till seeding. Growers have observed differences in decomposition among the cultivars that are currently produced; however, little information exists on the residue characteristics that distinguish among cultivars. The residue of commonly grown cultivars of spring barley, spring wheat, and winter wheat produced at multiple locations was analyzed for fiber characteristics and nutrient content. Information on decomposition of wheat and barley cultivars will aid growers in selecting cultivars for reduced tillage systems. This added information on the various cultivars and new releases will enhance the adoption of successful conservation tillage systems. Technical Abstract: Cropping systems in the dryland farming region of eastern Washington state 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 no-till seeding. Growers have observed differences in decomposition among the cultivars that are currently produced; however, little information exists on the residue characteristics that distinguish among cultivars. Several cultivars each of spring barley (SB), spring wheat (SW) and winter wheat (WW) from four locations and two crop years were analyzed for their neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), hemicellulose, cellulose, C and N contents, and winter wheat decomposition was tested in a laboratory incubation study. Cultivars of each crop type differed in their composition. Cultivars with indicators for rapid decomposition are Morex SB, Macon SW, and Eltan, Coda, and Stephens WW. Cultivars with potential for slower decomposition are Radiant SB, Nick, and Wawawai SW, and Bruehl, Finch, and Madsen WW. Foot rot resistant winter wheat varieties had higher NDF, ADF, ADL and cellulose, and lower hemicellulose than foot rot susceptible varieties. Laboratory incubation studies showed decomposition of winter wheat straw in soil was correlated with ADF (R2>0.66) and total N (R2>0.67). The goal of this research is to provide information to growers and researchers on the residue characteristics of cereal cultivars, and relate this information to farming systems that conserve soil and water. |