Enhanced efficiency nitrogen fertilizers: the What, When & Where. Tai McClellan Maaz Nitrogen Director, IPNI

Transcription

1 Enhanced efficiency nitrogen fertilizers: the What, When & Where Tai McClellan Maaz Nitrogen Director, IPNI

2 Enhanced efficiency fertilizers: Combining right source, time, and place Controlled release Stabilized N Coated or encapsulated Inhibitor treated Sulfur coated urea Polymer coated urea Urease Nitrification Snyder Soil Research. 55: Both

3 Mechanisms Plant uptake Urea NH 3 NH + 4 NO - 2 NO - 3 N 2 N 2 O NO N 2 O Urea hydrolysis Nitrification Denitrification

4 Mechanisms: Controlled release Polymer coated Urea Urea NH 3 NH + 4 NO 2 - N 2 O Urea hydrolysis Nitrification NO - 3 N 2 NO N 2 O Denitrification

5 Mechanisms: Urease inhibition Urea NH 3 NH + 4 NO - 2 NO - 3 N 2 N 2 O NO N 2 O Urea hydrolysis Nitrification Denitrification

6 Mechanisms: Nitrification inhibition Urea NH 3 NH + 4 NO - 2 NO - 3 N 2 N 2 O NO N 2 O Urea hydrolysis Nitrification Leaching Denitrification

7 Polymer coated urea

8 Impacts of polymer coated urea NH 3 Yield N 2 O Increase Decrease Snyder Soil Research. 55: NO 3 -

9 Effects on N 2 O emissions Inhibitors Urea Polymer coat Manure Control Red River Valley, Manitoba: Asgedom et al Agronomy J. 106:

10 Yield relative to untreated urea (%) Literature survey*: Yield effects of polymer coated urea Max = 171% Median = 0% Min = -48% Average = 3% 0-50 *381 observations. 21 published studies conducted in Alberta, Saskatchewan, Manitoba, Montana, or North Dakota

11 Grain N relative to untreated urea (%) Literature survey*: grain N effects of polymer coated urea Max = 158% Median = 0% Min = -55% Average = 1% *169 observations. 21 published studies conducted in Alberta, Saskatchewan, Manitoba, Montana, or North Dakota

12 Wheat yield (kg ha -1 ) Effects of placement: In the seedrow Toxicity mitigation near seed Malhi and Lemke Journal of Plant Nutrition. 36: Alternative to side-banded urea in fall and spring Haderlein et al The ScientificWorld. 1: Middleton et al Can. J. Soil Science. 84: McKenzie et al Can. J. Soil Science. 87: Non treated urea Polymer coated urea Fertilizer N rate Saskatchewan: Malhi et al Communications in Soil Science and Plant Analysis. 34:

13 Mean effect of polymer coated urea relative to uncoated urea on yields Blending Timing of Placement polymer coated urea and non-coated urea Fall may increase Banded grain yield under high moisture conditions Spring of Broadcast Boreal Transition and Aspen Parkland Incorporated Grant et al Field Seedrow Crops Research. 127: % -20% -10% 0% 10% 20% 30% 40% Polymer coated urea outperformed non-coated urea Winter wheat, S. Alberta: McKenzie et al Agron. J. 102: Winter wheat, Montana: Mohammed et al Agron. J. 108: Barley, C. Alberta: Nyborg et al Comm. Soil. Sci. Plant. Anal. 30: *Relative effects minus control Winter wheat, S. Alberta: Middleton et al Can. J. Soil Sci. 84:

14 Differences across the topography Yields*(kg ha -1 ) at different slope positions Fall banded urea Fall banded coated Spring banded urea Spring banded coated Lower Upper *Mean effect for 2 of 6 site years Spring wheat, SW Manitoba: Grant et al Agron. J

15 Inhibitors

16 Urease inhibitor NH 3 Yield N 2 O Increase Decrease Snyder Soil Research. 55: NO 3 - (one study, +nitrification inhibitor)

17 Urease inhibitor effects on NH 3 volatilization Urease inhibitor + Urease inhibitor Manitoba: Grant and Wu Crop Management.

18 Nitrification inhibitor NH 3 Yield N 2 O Increase Decrease Snyder Soil Research. 55: NO 3 -

19 Yield relative to untreated urea (%) Literature survey*: yield effects of urease inhibitors Max = 161% Median = 0% Min = -28% Average = 7% 0-50 *171 observation,16 published studies conducted in Alberta, Saskatchewan, Manitoba, Montana, or Dakotas

20 Grain N relative to untreated urea (%) Literature survey*: grain N effects of urease inhibitors Max = 160% Median = 1% Min = -47% Average = 3% 0-50 *121 observation,16 published studies conducted in Alberta, Saskatchewan, Manitoba, Montana, or Dakotas

21 Yield (kg ha -1 ) Effects of placement: In the seedrow Non treated urea Urease inhibitor Polymer coated urea Fertilizer N rate Malhi et al Communications in Soil Science and Plant Analysis. 34:

22 Recovered fertilizer in grain (kg N ha -1 ) Effects of timing: Fall vs Spring Other studies comparing effects of urease inhibitor: Non-treated Fall broadcasted Urea treated with urea: urease Yields inhibitor increased by 3 to 8% Spring broadcasted treated urea*: Yields decreased by 0 to -1% *Winter wheat, S. Alberta: McKenzie et al Agron. J. 102: *Spring only data Winter wheat, Montana: Mohammed et al Agron. J. 108: Forages, Alberta: Karamanos and Stevenson Can. J. Plant Sci. 93: Winter wheat, Montana: Romero et al SSSAJ. 81:

23 Effect across topography Well drained: -Yields were 3% less with urea + urease inhibitor -Differences not significant Poorly drained: -Yields were 1% more with urea + urease inhibitor -Differences only significant 1 of 4 site years Spring wheat, Manitoba: Tiessen et al Can. J. Soil Sci. 85:

24 Effect of combining with a nitrification inhibitor Urease inhibitor Urease + nitrification inhibitor Yield relative to non-treated urea -1 to -7% 5 to 29% Winter wheat, Montana: Mohammed et al Agron. J. 108: Winter wheat, Beiseker, Alberta: Jensen Personal communication. Forage, Youngstown, Alberta: Jensen, Personal communication.

25 Summary Enhanced efficiency fertilizers can reduce nitrogen losses in high risk environments, but consider modes of action [1] Variable effects on yields Polymer coated urea and urease inhibitors Placement in the seed row Fall application with high loss risk Blending of non- and polymer coated urea in spring Combing urease and nitrification inhibitors may provide additional benefits for enhanced efficiency of urea [1] Snyder et al Agriculture, Ecosystems, and Environment. 133:

26 Thank you Tai McClellan Maaz