Improving Nitrogen Use Efficiency in Cereal Grain Production with Optical Sensing and Variable Rate Application

In 2001, N fertilizer prices nearly doubled as a result of increased natural gas prices. This was further troubling when considering that the world N use efficiency (NUE) in cereal grain production averages only 33%. Methods to improve NUE in winter wheat (Triticum aestivum L.) have not included high spatial-resolution management based on sensed plant growth properties nor on midseason prediction of grain yield. Our objective was to determine the validity of using inseason estimates of grain yield (INSEY) and a response index (RI) to modulate N at 1-m 2 spatial resolution. Four winter wheat field experiments were conducted that evaluated prescribed midseason N applications compared with uniform rates that simulated farmer practices. Our methods recognize that each 1-m 2 area in wheat fields needs to be sensed and managed independently and that the need for fertilizer N is temporally dependent. Averaged over locations, NUE was improved by >15% when N fertilization was based on optically sensed INSEY, determined for each 1-m 2 area, and a RI compared with traditional practices at uniform N rates.

[1]  E. V. Lukina,et al.  NITROGEN FERTILIZATION OPTIMIZATION ALGORITHM BASED ON IN-SEASON ESTIMATES OF YIELD AND PLANT NITROGEN UPTAKE , 2001 .

[2]  John B. Solie,et al.  In‐Season Prediction of Potential Grain Yield in Winter Wheat Using Canopy Reflectance , 2001 .

[3]  John B. Solie,et al.  Effect of growth stage and variety on spectral radiance in winter wheat , 2000 .

[4]  John B. Solie,et al.  Submeter Spatial Variability of Selected Soil and Bermudagrass Production Variables , 1999 .

[5]  William R. Raun,et al.  Improving Nitrogen Use Efficiency for Cereal Production , 1999 .

[6]  R. W. Whitney,et al.  Microvariability in Soil Test, Plant Nutrient, and Yield Parameters in Bermudagrass , 1998 .

[7]  Steven R. Silva,et al.  Movement of nitrate fertilizer to glacial till and runoff from a claypan soil , 1996 .

[8]  Craig F. Drury,et al.  Influence of controlled drainage-subirrigation on surface and tile drainage nitrate loss , 1996 .

[9]  R. Rickman,et al.  MODWht3 : A development-driven wheat growth simulation , 1996 .

[10]  R. W. Whitney,et al.  Use of Spectral Radiance for Correcting In-season Fertilizer Nitrogen Deficiencies in Winter Wheat , 1996 .

[11]  W. Raun,et al.  Nitrate Leaching in Continuous Winter Wheat: Use of a Soil‐Plant Buffering Concept to Account for Fertilizer Nitrogen , 1995 .

[12]  P. Fixen,et al.  Effects of tillage, nitrogen placement, and wheel compaction on denitrification rates in the corn cycle of a corn‐oats rotation , 1994 .

[13]  J. Schepers,et al.  Post-Anthesis Nitrogen Loss from Corn , 1993 .

[14]  C. W. Richardson,et al.  Sediment and Nutrient Loss from Clay Soils as Affected by Tillage , 1992 .

[15]  S. Datta,et al.  Direct Measurement of Ammonia and Denitrification Fluxes from Urea Applied to Rice , 1991 .

[16]  J. S. Schepers,et al.  Simultaneous determination of total C, total N, and 15N on soil and plant material , 1989 .

[17]  D. Fowler,et al.  No-till Winter Wheat Production on the Canadian Prairies: Placement of Urea and Ammonium Nitrate Fertilizers , 1989 .

[18]  G. Langdale,et al.  Nitrogen cycling in a wheat crop: soil, plant, and aerial nitrogen transport , 1987 .

[19]  E. Paul,et al.  GASEOUS NITROGEN LOSSES FROM CROPPED AND SUMMER- FALLOWED SOILS' , 1982 .

[20]  L. Fenn,et al.  Field Measurements of Ammonia Volatilization from Surface Applications of Ammonium Salts to a Calcareous Soil1 , 1977 .

[21]  Gary A. Peterson,et al.  Nitrogen Content of Winter Wheat During Growth and Maturation1 , 1976 .

[22]  R. Hardy,et al.  Nitrogen fixation research: a key to world food? , 1975, Science.

[23]  E. C. Large.  GROWTH STAGES IN CEREALS ILLUSTRATION OF THE FEEKES SCALE , 1954 .