caa a22 4500 445864559 CHVBK 20180317145453.0 cr unu---uuuuu 170323e20110801xx s 000 0 eng 10.1007/s11119-010-9190-5 doi (NATIONALLICENCE)springer-10.1007/s11119-010-9190-5 Profitability of variable rate nitrogen application in wheat production [Elektronische Daten] [Christopher Boyer, B. Wade Brorsen, John Solie, William Raun] Using plant sensing to determine the amount of nitrogen (N) to apply has the potential to increase profits in wheat (Triticum aestivum) production by reducing N cost or by increasing grain yield. The objective of this paper was to determine if yields and profits from experimental trials that used a precision N applicator to apply N were significantly different from trials that applied pre-determined amounts of N. Across Oklahoma, USA, experiments were designed to test 10N treatments that included two variable rate treatments (VRT), two uniform rate treatments (URT) where the level of N applied was based on optical reflectance measurements (ORM), and six conventional treatments (i.e., pre-determined uniform rates of N). Data included treatments during 2005-2009 from eight different locations. Results indicated no statistical difference in yields between the conventional treatments that apply 90kgha−1 of N and the VRT and URT treatments. On average, the conventional treatment that applied 90kgha−1 of top-dress N produced the largest yield, with a VRT treatment producing the third largest yield. Profits were calculated for each treatment using a partial budget. On average, the treatment that received 90kgha−1 of top-dress N was the most profitable even though the pre-plant N (anhydrous ammonia) had a cost advantage relative to top-dress N (urea and ammonium nitrate). Springer Science+Business Media, LLC, 2010 Profitability nationallicence Variable rate application nationallicence Uniform rate application nationallicence Optical reflectance sensing nationallicence Wheat nationallicence N : Nitrogen nationallicence NUE : Nitrogen use efficiency nationallicence ORM : Optical reflectance measurements nationallicence NFOA : Nitrogen fertilizer optimization algorithm nationallicence NRS : Nitrogen rich strip nationallicence NDVI : Normalized difference vegetation index nationallicence VRT : Variable rate treatment nationallicence URT : Uniform rate treatment nationallicence NH3 : Anhydrous ammonia nationallicence AN : Ammonium nitrate nationallicence UAN : Urea ammonium nitrate nationallicence LCB : Lake Carl Blackwell nationallicence USDA : United States Department of Agriculture nationallicence NASS : National Agricultural Statistics Service nationallicence LR : Likelihood ratio nationallicence Boyer Christopher Department of Agricultural Economics, Oklahoma State University, 74078-6026, Stillwater, OK, USA aut Wade Brorsen B. Department of Agricultural Economics, Oklahoma State University, 74078-6026, Stillwater, OK, USA aut Solie John Department of Biosystems and Agricultural Engineering, Oklahoma State University, 74078-6016, Stillwater, OK, USA aut Raun William Department of Plant and Soil Sciences, Oklahoma State University, 74074-6028, Stillwater, OK, USA aut Precision Agriculture Springer US; http://www.springer-ny.com 12/4(2011-08-01), 473-487 1385-2256 12:4<473 2011 12 11119 https://doi.org/10.1007/s11119-010-9190-5 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11119-010-9190-5 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Boyer Christopher Department of Agricultural Economics, Oklahoma State University, 74078-6026, Stillwater, OK, USA aut NATIONALLICENCE 700 1- Wade Brorsen B. Department of Agricultural Economics, Oklahoma State University, 74078-6026, Stillwater, OK, USA aut NATIONALLICENCE 700 1- Solie John Department of Biosystems and Agricultural Engineering, Oklahoma State University, 74078-6016, Stillwater, OK, USA aut NATIONALLICENCE 700 1- Raun William Department of Plant and Soil Sciences, Oklahoma State University, 74074-6028, Stillwater, OK, USA aut NATIONALLICENCE 773 0- Precision Agriculture Springer US; http://www.springer-ny.com 12/4(2011-08-01), 473-487 1385-2256 12:4<473 2011 12 11119 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer