Managing Nitrogen for Corn. Jim Camberato Dan Emmert Bob Nielsen Brad Joern

Transcription

1 Managing Nitrogen for Corn Jim Camberato Dan Emmert Bob Nielsen Brad Joern

2 Thank You! Pioneer for donating seed for all Purdue Ag. Farm trials Beck s for providing seed to cooperating growers and conducting several trials Individual farmers for their efforts and monetary losses due to reduced yield and excess N Industry agronomists for coordinating tests with farmers A&L Laboratories for reduced price analyses Mary S. Rice Farm Foundation for partial funding of this work and the PAC staffs

3 Grain/Nitrogen Prices Year $/bushel $/pound N A bushel buys X lbs N ? 0.30? 12

4 Topics to be discussed Experimental site characteristics Response patterns to N Economic optimum N rates Tools for fine-tuning recommendations

5 2006 Experiments 32 site-situations Many field scale Grain yield via yield monitor % CS 84% UAN 98% Sidedress 11 4

6 Sebewa 1 2 Rawson Glynwood Chalmers, Toronto, Raub, Wingate Iva Blount Pewamo Crosby Cyclone 4 Muren Ragsdale, Ade Uniontown 11 Cobbsfork Soil Series

7 Apr. Aug. rainfall Normal

8 Nitrogen rate treatments Low rate is starter only, or 0 N 40 or 50 lb N/acre increments (5 or 6) 2-6 replications per trial

9 lb N/acre 79 Plant 4/23 Fert. 5/22 Photo 8/4

10 Bushels per acre Grain yield response to N W. Lafayette-Chalmers SiCL 31bu/a 1.3 lb/bu 13 bu/a 3.0 lb/bu 10 bu/a 4.0 lb/bu 2 bu/a 20 lb/bu Nitrogen, lb/acre 3 bu/a 13 lb/bu

11 Bushels per acre -$1 from Economic Optimum N Rate W. Lafayette-Chalmers SiCL $3.50/bu corn - $0.30/lb N lb/a -$1 /A lb/a Economic Optimum Nitrogen, lb/a

12 Bushels per acre -$5 from Economic Optimum N Rate W. Lafayette-Chalmers SiCL $3.50/bu corn - $0.30/lb N lb/a -$5 /A bu/a Economic Optimum Nitrogen, lb/a

13 Bushels per acre -$10 from Economic Optimum N Rate W. Lafayette-Chalmers SiCL $3.50/bu corn - $0.30/lb N lb/a -$10 /A bu/a Economic Optimum Nitrogen, lb/a

14 NEPAC-Rawson Davis-Blount, Pewamo Pinney-Sebewa Optimum N rate, lb/acre TRIALS C/S Optimum N rate at $3.50 corn/30 N Iva NEPAC, Glynwood Cyclone, Crosby Cyclone, Crosby Grant Co. Rensselaer Uniontown, Ragsdale Ragsdale Iva ACRE-Chalmers, Raub Feldun-Muren Brookston Uniontown, Ragsdale SEPAC-Cobbsfork Ripley Co. SWPAC-Ade Decatur Co. Uniontown, Ragsdale Crosby, Miami Averaging bu/acre at lb 15N/acre

15 2006 On-Farm trial C/S

16 No relationship between max. yield and opt. N rate 250 Max. yield, bu/a y = 0.04x R 2 = N rate for max. yield, lb/a

17 Illinois and Ohio on-line N calculators

18 Comparison to Ohio and Illinois online N calculators CS $3.50/30 State -$1 Econ. Opt. -1$ C. Illinois Indiana Ohio

19 Comparison to Ohio and Illinois online N calculators CS $3.50/30 State -$1 Econ. Opt. -1$ C. Illinois Indiana (-$5) (-5$) Ohio

20 Economic optimum N at different Grain and N prices 2006 trials Grain Value Nitrogen cost, /lb $ $ $ $

21 2006 TRIALS +50 /bu increases econ. opt. N 3 10 lb N/acre +10 /lb N decreases econ. opt. N 6 14 lb N/acre

22 Has N response changed over the years? Is more or less N needed to make optimum yield?

23 N response on Drummer/Chalmers Shape of response curve similar, but yield higher now

24 Econ. opt.* mid-range in 2006, but yield bu/a greater *Econ. opt. $3.00 & 30

25 One factor affecting N rate needed is soil nitrogen supply Origin of Soil N supply Residues previous crop Soil organic matter Weather Release of N from residues and organic matter Loss of N originating from residues and organic matter

26 Soil nitrogen supply affects N needed to obtain Opt. Econ. Yield EONR*, lb/acre *$3.50/bu & 30 N/lb Low soil N High soil N Yield with no fert. N, bu/acre

27 Is PSNT useful for determining N rates in corn-soybean rotation? Grain yield at low N, bu/a Soil nitrate, ppm NO

28 How do we do better? Computer model N availability and loss, predict: N carryover from previous crop N mineralization from OM and residues N loss and yield potential Use sensors that measure plant reflectance as an assessment of plant N content and need for more N

29 Crop sensor tools with potential Minolta SPAD meter Measures transmittance of NIR and red wavelengths through leaf tissue. Calculates a leaf greenness value that correlates to chlorophyll content and leaf nitrogen status. R.L. Nielsen, NitrogenMgmt2007.ppt

30 Crop sensor tools with potential Crop Circle canopy sensor by Holland Scientific. Emits NIR and visible wavelengths, then measures reflectance of both that correlate with leaf greenness. Reflectance data used to estimate plant health. R.L. Nielsen, NitrogenMgmt2007.ppt

31 Sensors relate well to each other 2006 Purdue N Trials, Camberato et al.; R.L. Nielsen, NitrogenMgmt2007.ppt

32 SPAD values relate well to yield 2006 Purdue N Trials, Camberato et al.; R.L. Nielsen, NitrogenMgmt2007.ppt

33 CC values relate well to yield 2006 Purdue N Trials, Camberato et al.; R.L. Nielsen, NitrogenMgmt2007.ppt

34 CropCircle and SPAD similarities Reference strip for each field and hybrid Tall corn and high clearance equip.

35 CropCircle vs SPAD differences CC is less time consuming and makes continuous readings CC can be linked to a variable rate applicator for on-the-go prescriptive N application

36 QUESTIONS?

37 On Farm Trials lb N/acre in lb N/acre increments (5-6 rates) >350 of row 2 or more replications, 4 or more preferred Harvest center of each plot (ex. 6 of 12) Calibrated yield monitor preferred