Nitrogen and Phosphorus Recalibration for Sunflower Eric Schultz, MS Student, NDSU Dave Franzen, NDSU Extension Soil Specialist
Current recommendations N rate = (0.05 x Yield potential) - N credits P recommendations assume critical level of 16 ppm Significant P rates needed at <15 ppm
Recommendations have not changed for about 40 years- 1970s research Herbicide resistant systems Disease resistance Downy mildew, sunflower rust, Sclerotinia Crop rotations early rotations included fallow Tillage systems conservative
Experimental Design RCBD, split plot, 4 replications Main plots 6 N Rates: 0 200 lbs N / acre ammonium nitrate or Agrotain + urea Sub plots 2014: 4 P Rates: 0 90 lbs P 2 O 5 / acre 2015: 2 P Rates: 0, 60 lbs P 2 O 5 / acre triple superphosphate
Yield, pounds per acre 4000 2014 Sunflower Yield, N Treatment Rate only 3500 3000 2500 2000 1500 1000 500 0 y = -0.0111x 2 + 3.8011x + 1530 R² = 0.0645 0 50 100 150 200 250 N Treatment Rate, lbs N per acre
Yield, pounds per acre 4000 3500 2014 Sunflower Yield, Including Soil Test N y = -0.0112x 2 + 5.352x + 1241.9 R² = 0.1062 3000 2500 2000 1500 1000 500 0 0 100 200 300 400 500 Total known available N, lbs per acre
Yield, lbs per acre 4500 Eastern ND Sunflower Yield, 2014-2015 4000 3500 3000 2500 2000 1500 1000 500 0 y = -0.0115x 2 + 4.5992x + 1486.1 R² = 0.0267 0 50 100 150 200 250 300 350 400 TKAN, lbs per acre
Yield, lbs per acre 4500 4000 3500 Eastern ND No-Till Sunflower Yield, 2014-2015 y = -0.0098x 2 + 4.7827x + 1277 R² = 0.1153 3000 2500 2000 1500 1000 500 0 0 50 100 150 200 250 300 350 TKAN, lbs per acre
Yield, lbs per acre 4000 Western ND Sunflower Yield, 2014-2015 3500 3000 2500 2000 1500 1000 500 0 y = -0.0046x 2 + 4.1865x + 1456.6 R² = 0.138 0 50 100 150 200 250 300 350 Total known available N, lbs per acre
Sunflower oil, percent 50 Western ND Sunflower Oil, 2014-2015 48 46 44 42 40 38 36 34 32 30 y = -0.0008x + 39.262 R² = 0.0005 0 50 100 150 200 250 300 350 Total known available N, lbs per acre
Sunflower oil, percent 47 46 2015 Bottineau Sunflower Oil, two sites y = -0.0121x + 44.665 R² = 0.3875 45 44 43 42 41 40 39 0 50 100 150 200 250 300 Total known available N, lbs per acre
Site ID STP ppm Calibration level P response? B-ND14 11 M No DS-ND14 8 M No H-ND14 9 M No ON-SD14 10 M No AD-ND15 3 VL No B-ND15 2 VL No BF-ND15 8 M No BN-ND15 7 L No BS-ND15 8 M No CH-ND15 8 M No D-ND15 6 L No L-ND15 7 L No C-SD15 8 M No VL M testing sites, 2014-2015
P responding sites, 2014-2015, only the W-ND15 site was economically beneficial (high yield near 4,000 lb/acre) Site ID STP (ppm) Calibration level P response? Yield increase A-ND14 5 L Yes 320 lbs/a BF-ND14 17 VH Yes 220 lbs/a W-ND15 11 M Yes 281 lbs/a
New Sunflower Fertilizer Recommendations Eric Schultz, MS Student, NDSU Dave Franzen, NDSU Extension Soil Specialist
Additional datasets included: 2012-2013 N trials, 4 sites 2 oilseed, 2 confection 0-200 lbs N/acre 2014-2015 N & P, North Dakota sites
New recommendations: Region and tillage based Diminishing returns for N Economic production function } Return to N model Return to N model: Developed by Sawyer and Nafziger, 2005 Used for corn and wheat recommendations
Other considerations for the updated recommendations: New Sunflower fields - 2-4 foot soil sample for N - if >30 lbs N, additional N credit Oil Lodging Disease
Percent Oil 47 46 2015 Bottineau Sunflower Oil, two sites y = -0.0121x + 44.665 R² = 0.3875 45 44 43 42 41 40 39 0 50 100 150 200 250 300 Total known available N, lbs per acre
Percent Sunflower Lodging 100 80 Percent Sunflower Lodging vs. N Rate, Bottineau, ND, 2015 y = 0.3058x - 0.9866 R² = 0.5737 60 40 20 0 0 50 100 150 200 250 300 Total known available N, lbs per acre
Yield, lbs per acre 4000 Western North Dakota Sunflower Yield 3500 3000 2500 2000 1500 1000 500 0 y = -0.006x 2 + 4.3292x + 1451.2 R² = 0.1249 0 50 100 150 200 250 300 350 Total known available N, lbs per acre
500 Western ND Return to N Sunflower price $0.12 (bottom) to $0.24 (top) per pound N cost $0.20 to $0.60 per pound Max. return at $0.15 and $0.45 is about 120 lbs 400 300 200 12SF20N 15SF20N 18SF20N 21SF20N 24SF20N 12SF30N 15SF30N 18SF30N 21SF30N 24SF30N 12SF40N 15SF40N 18SF40N 21SF40N 24SF40N 12SF50N 15SF50N 18SF50N 21SF50N 24SF50N 12SF60N 15SF60N 18SF60N 21SF60N 24SF60N 100 0 50 100 150 200 250 300
Sunflower Seed Price $ per pound N cost, $ per pound 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 Total Known Available N, pounds per acre 0.09 150 74 0 0 0 0 0 0 0 0.12 150 144 74 7 0 0 0 0 0 0.15 150 150 129 74 20 0 0 0 0 0.18 150 150 150 120 74 29 0 0 0 0.21 150 150 150 150 113 74 35 0 0 0.24 150 150 150 150 150 108 74 40 7 0.27 150 150 150 150 150 136 104 74 44 0.30 150 150 150 150 150 150 129 101 74 Add 10 lbs for confections except for 0 values
Yield, lbs per acre 4000 Eastern North Dakota No-Till Sunflower Yield 3500 3000 2500 2000 1500 1000 500 0 y = -0.0093x 2 + 5.5523x + 1412.9 R² = 0.112 0 50 100 150 200 250 300 350 400 Total known available N, pounds per acre
500 Eastern ND No-till Return to N Sunflower price $0.12 (bottom) to $0.24 (top) per pound N cost $0.20 to $0.60 per pound Max. return at $0.15 and $0.45 is about 110 lbs 400 300 200 12SF20N 15SF20N 18SF20N 21SF20N 24SF20N 12SF30N 15SF30N 18SF30N 21SF30N 24SF30N 12SF40N 15SF40N 18SF40N 21SF40N 24SF40N 12SF50N 15SF50N 18SF50N 21SF50N 24SF50N 12SF60N 15SF60N 18SF60N 21SF60N 24SF60N 100 0 50 100 150 200 250 300
Sunflower Seed Price $ per pound N cost, $ per pound 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 Total Known Available N, pounds per acre* 0.09 150 97 49 4 0 0 0 0 0 0.12 150 135 74 61 25 0 0 0 0 0.15 150 150 127 97 68 39 11 0 0 0.18 150 150 150 122 97 73 49 25 0 0.21 150 150 150 140 119 97 76 56 35 0.24 150 150 150 150 135 116 97 79 61 0.27 150 150 150 150 150 131 114 97 81 0.30 150 150 150 150 150 143 127 112 97 Add 10 lbs for confections except for 0 values
Yield, lbs per acre 5000 4500 Eastern North Dakota Conventional Till Sunflower Yield y = -0.0166x 2 + 5.5523x + 1781.2 R² = 0.0735 4000 3500 3000 2500 2000 1500 1000 500 0 0 50 100 150 200 250 300 350 400 450 Total known available N, lbs per acre
Sunflower rust severity rating as a result of N rate, Dickinson, ND, 2015. N rate, lb per acre Sunflower rust rating 0 0.65 a 40 1.51 ab 80 2.25 b 120 1.53 ab 160 1.25 ab 200 1.63 ab Ratings made on images obtained by retired plant pathologist Roger Ashley and rated by Dr. Samuel Markel, NDSU Extension Plant Pathologist.
Eastern conventional till oilseed Sunflower Seed Price $ per pound N cost, $ per pound 0.20 0.30 0.40 0.50 0.60 0.70 0.80 0.90 1.00 Total Known Available N, pounds per acre* 0.09 133 104 76 48 22 0 0 0 0 0.12 148 125 104 83 62 42 22 0 0 0.15 157 139 122 104 87 71 54 38 22 0.18 163 148 133 119 104 90 81 62 49 0.21 167 155 142 129 117 104 92 80 68 0.24 172 159 148 137 126 115 104 94 83 0.27 173 162 153 143 133 124 114 104 95 0.30 175 166 157 148 139 130 122 113 106 Add 10 lbs for confections except for 0 values
500 Eastern ND Conventional Till Confections Return to N Sunflower price $0.12 (bottom) to $0.24 (top) per pound N cost $0.20 to $0.60 per pound Max. return at $0.15 and $0.45 is about 135 lbs 400 300 200 100 12SF20N 15SF20N 18SF20N 21SF20N 24SF20N 12SF30N 15SF30N 18SF30N 21SF30N 24SF30N 12SF40N 15SF40N 18SF40N 21SF40N 24SF40N 12SF50N 15SF50N 18SF50N 21SF50N 24SF50N 12SF60N 15SF60N 18SF60N 21SF60N 24SF60N 0 50 100 150 200 250 300
Phosphorus? Zero Phosphorus Micronutrient-like Overall only 3 responses, 1 economic Sufficient uptake from soil, even low (<8 ppm) sites Dry matter, yes Seed yield? No
NDSU Ext. Circular available by March 1 st Online N Calculator in the works
Acknowledgements National Sunflower Association National Science Foundation (NSF-Grant)