Author
ARNALL, BRIAN - Oklahoma State University | |
MALLARINO, A.P. - Iowa State University | |
RUARK, MATTHEW - University Of Wisconsin | |
Varvel, Gary | |
SOLIE, JOHN - Oklahoma State University | |
STONE, MARVIN - Oklahoma State University | |
MULLOCK, JEREMIAH - Oklahoma State University | |
TAYLOR, RANDY - Oklahoma State University | |
RAUN, BILL - Oklahoma State University |
Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 6/13/2013 Publication Date: 7/10/2013 Citation: Arnall, B., Mallarino, A., Ruark, M.D., Varvel, G.E., Solie, J.B., Stone, M.L., Mullock, J., Taylor, R., Raun, B. 2013. Relationship between grain crop yield potential and nitrogen response. Agronomy Journal. 105(5): 1335-1344. DOI:10.2134/agronj2013.0034. Interpretive Summary: The debate about whether nitrogen fertilizer recommendations should be based on yield level (yield potential) for cereal grains continues, but in many cases, the yield potentials are controlled by environmental conditions. To adequately test this, our objective was to evaluate the relationship between yield potential (yield level) and nitrogen responsiveness in long-term winter wheat and corn field experiments in Stillwater, OK (53 years), Altus, OK (45 years), Arlington, WI (49 years), and Shelton, NE (11 years). Nitrogen responsiveness or the response index (RI) was determined by dividing the grain yield from high nitrogen rate plots by the yield from either the 0-nitrogen fertilizer check (RI 0-nitrogen) or medium nitrogen rate plots (RI mid-nitrogen). Linear relationships between maximum yield, RI (0-nitrogen), RI (mid-nitrogen), and year were then determined. For the 5 long-term trials in this study, yield and nitrogen responsiveness were not related whether or not a medium nitrogen rate or the check plot (0-N) was used to determine RI. Because both yield level and nitrogen responsiveness impact nitrogen demand, and are independent from each other, mid-season estimates of both should be included in the formulation of nitrogen fertilizer recommendations. Technical Abstract: Cereal grain fertilizer nitrogen (N) recommendations should conform to accepted theory. The objective of this study was to evaluate the relationship between yield potential (yield level) and N responsiveness in long-term winter wheat (Triticum aestivum L.) and maize (Zea mays L.) field experiments in Stillwater, OK (53 years), Altus, OK (45 years), Arlington, WI (49 years), and Shelton, NE (11 years). Nitrogen responsiveness or the response index (RI) was determined by dividing the grain yield from high N rate plots by the yield from either the 0-N fertilizer check (RI 0-N) or medium N rate plots (RI mid-N). Linear relationships between maximum yield, RI 0-N, RI mid-N, and year were then determined. For the 5 long-term trials reported here, yield and N responsiveness were not related whether or not a medium N rate or the check plot (0-N) was used to determine RI. Because both yield level and N responsiveness impact N demand, and are independent from each other, mid-season estimates of both should be included in the formulation of N fertilizer recommendations. |