Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: May 11, 2010
Publication Date: October 31, 2010
Citation: Tanaka, D.L., Liebig, M.A., Merrill, S.D., 2010. Crop sequence and tillage influences on dryland spring wheat production. ASA-CSSA-SSSA Annual Meeting Abstracts. 234-3. Technical Abstract: Cropping systems and management practices for spring wheat production have changed during the past half century. Greater emphasis on soil and water conservation has helped to stabilize crop yields. Our objectives were to determine the influences of six crop sequences and two tillage practices on spring wheat grain production and N concentration and grain precipitation- use efficiency in the northern Great Plains. The six crop sequences were: 1) continuous spring wheat, residue left in place; 2)continuous spring wheat, residue removed; 3) spring wheat - millet; 4) spring wheat - safflower - fallow; 5) spring wheat - safflower - rye partial cover crop; and 6) spring wheat - fallow. Tillage practices were minimum-till (MT, 30 to 60% soil surface covered by residue) and no-till (NT, >60% soil surface covered by residue). By including crops other than spring wheat or fallow in crop sequences, spring wheat grain yield increased by at least 11% over monoculture continuous spring wheat. When averaged over all crop sequences, NT had greater spring wheat grain yields than MT, but grain N concentration for NT was less than MT. During three years when growing season precipitation (May through August) was <12cm, spring wheat-millet crop sequence had significantly greater spring wheat grain yield than other crop sequences.