Free Standard AU & NZ Shipping For All Book Orders Over $80!
Register      Login
Soil Research Soil Research Society
Soil, land care and environmental research
RESEARCH ARTICLE (Open Access)

Influence of enhanced efficiency fertilisation techniques on nitrous oxide emissions and productivity response from urea in a temperate Australian ryegrass pasture

H. C. Suter A D , H. Sultana A , R. Davies B , C. Walker C and D. Chen A
+ Author Affiliations
- Author Affiliations

A Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, Parkville, Vic. 3010, Australia.

B BASF Australia, Freshwater Place, Southbank, Vic. 3006, Australia.

C Incitec Pivot Fertilisers, PO Box 54, North Geelong, Vic. 3215, Australia.

D Corresponding author. Email: helencs@unimelb.edu.au

Soil Research 54(5) 523-532 https://doi.org/10.1071/SR15317
Submitted: 29 October 2015  Accepted: 17 March 2016   Published: 6 July 2016

Journal Compilation © CSIRO Publishing 2016 Open Access CC BY-NC-ND

Abstract

The effect of a nitrification inhibitor on nitrous oxide (N2O) emissions across seasons, the effect of a urease inhibitor and a fine particle spray (both targeting ammonia (NH3) loss) on N2O emissions, and the potential for productivity benefits and efficiencies by using these enhanced efficiency fertilisers (EEFs) were investigated in temperate pastures. The study compared three treatments over an eight month period (April to December 2010): (1) urea (U), (2) urea with a nitrification inhibitor (3,4-dimethylpyrazole phosphate) (DMPP), and (3) urea with a urease inhibitor (N-(n-butyl) thiophosphoric triamide (NBTPT)) (GU). In autumn, when NH3 loss was predicted to be high, the effect of urea applied as a fine particle spray (containing urea, NBTPT and gibberellic acid (10 g ha–1)) (FPA) on N2O emissions and productivity was determined.

N2O emissions from urea applied to pastures were low, and were larger in spring than autumn due to soil moisture and temperature. DMPP was an effective tool for mitigating N2O emissions, decreasing fertiliser-induced N2O emissions relative to urea by 76% over eight months. However, the urease inhibitor (NBTPT) (GU) increased N2O emissions from urea by 153% over eight months. FPA had no impact on N2O, but was only examined during periods of low emission (autumn). No significant biomass productivity, agronomic efficiency benefits, or improvements in apparent fertiliser recovery were observed with the DMPP and GU treatments. A significant biomass productivity benefit was observed with the FPA treatment 55 days after fertiliser was applied, most likely because of the gibberellic acid. The outcomes highlight that although DMPP effectively decreased N2O emissions it had no impact on biomass productivity compared with urea. The use of the GU increased N2O emissions by preserving NH3 in the soil. To avoid this a lower rate of N should be applied with the urease inhibitor.

Additional keywords: 3,4-dimethylpyrazolephosphate, fine particle spray, nitrification inhibitor, N-(n-butyl) thiophosphoric triamide, urease inhibitor.


References

Abalos D, Jeffery S, Sanz-Cobena A, Guardia G, Vallejo A (2014) Meta-analysis of the effect of urease and nitrification inhibitors on crop productivity and nitrogen use efficiency. Agriculture, Ecosystems & Environment 189, 136–144.
Meta-analysis of the effect of urease and nitrification inhibitors on crop productivity and nitrogen use efficiency.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXnslGqs7Y%3D&md5=05c0ff60ecf5bb5ce2cf3b91bc7194b9CAS |

Bell MJ, Rees RM, Cloy JM, Topp CFE, Bagnall A, Chadwick DR (2015) Nitrous oxide emissions from cattle excreta applied to a Scottish grassland: Effects of soil and climatic conditions and a nitrification inhibitor. The Science of the Total Environment 508, 343–353.
Nitrous oxide emissions from cattle excreta applied to a Scottish grassland: Effects of soil and climatic conditions and a nitrification inhibitor.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXitV2isL%2FK&md5=1a116667f44fcf1d282b4415b337e0a9CAS | 25497356PubMed |

Biddiscombe E, Arnold G, Scurfield G (1962) Effects of Gibberellic acid on pasture and animal production in winter. Australian Journal of Agricultural Research 13, 400–413.
Effects of Gibberellic acid on pasture and animal production in winter.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaF3sXhtFWitA%3D%3D&md5=0045962f63f090a7ff43ca92474282b5CAS |

Butterbach-Bahl K, Baggs EM, Dannenmann M, Kiese R, Zechmeister-Boltenstern S (2013) Nitrous oxide emissions from soils: how well do we understand the processes and their controls? Philosophical Transactions of the Royal Society, B: Biological Sciences 368, 20130122.
Nitrous oxide emissions from soils: how well do we understand the processes and their controls?Crossref | GoogleScholarGoogle Scholar |

Carey PL, Jiang S, Roberts AH (2012) Pasture dry matter responses to the use of a nitrification inhibitor: a national series of New Zealand farm trials. New Zealand Journal of Agricultural Research 55, 63–72.
Pasture dry matter responses to the use of a nitrification inhibitor: a national series of New Zealand farm trials.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XjtFyitrs%3D&md5=6cdab99d20156d2208361fc393468bceCAS |

Chen D, Suter HC, Islam A, Edis R, Freney JR, Walker CN (2008) Prospects of improving efficiency of fertilizer nitrogen in Australian agriculture; a review of enhanced efficiency fertilizers. Australian Journal of Soil Research 46, 289–301.
Prospects of improving efficiency of fertilizer nitrogen in Australian agriculture; a review of enhanced efficiency fertilizers.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXns1OktLw%3D&md5=fec61f7dd15fe4ea2a2bc5ea7113200cCAS |

Chen D, Suter HC, Islam A, Edis R (2010) Influence of nitrification inhibitors on nitrification and nitrous oxide (N2O) emission from a clay loam soil fertilized with urea. Soil Biology & Biochemistry 42, 660–664.
Influence of nitrification inhibitors on nitrification and nitrous oxide (N2O) emission from a clay loam soil fertilized with urea.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXis1Sgtrw%3D&md5=cb0fbf1d12401ca061462b81b933ca1fCAS |

Ciarlo E, Conti M, Bartoloni N, Rubio G (2008) Soil N2O emissions and N2O/(N2O+N2) ratio as affected by different fertilization practices and soil moisture. Biology and Fertility of Soils 44, 991–995.
Soil N2O emissions and N2O/(N2O+N2) ratio as affected by different fertilization practices and soil moisture.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXos1WltLw%3D&md5=e685e7c6c7cc18cb089a89111f845c6cCAS |

Dawar K, Zaman M, Rowarth JS, Blennerhassett J, Turnbull MH (2011) Urease inhibitor reduces N losses and improves plant-bioavailability of urea applied in fine particle and granular forms under field conditions. Agriculture, Ecosystems & Environment 144, 41–50.
Urease inhibitor reduces N losses and improves plant-bioavailability of urea applied in fine particle and granular forms under field conditions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3MXhsFCqsLnL&md5=fb5302fdd4252b37927c715ce62910fbCAS |

Dawar K, Zaman M, Rowarth JS, Turnbull MH (2012) Applying urea with urease inhibitor (N-(n-butyl) thiophosphoric triamide) in fine particle application improves nitrogen uptake in ryegrass (Lolium perenne L.). Soil Science and Plant Nutrition 58, 309–318.
Applying urea with urease inhibitor (N-(n-butyl) thiophosphoric triamide) in fine particle application improves nitrogen uptake in ryegrass (Lolium perenne L.).Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XpvV2isr8%3D&md5=052c8ee7d1491ffa5947842a3efae363CAS |

Department of Climate Change and Energy Efficiency (DCCEE) (2011) ‘Australian national greenhouse accounts: national greenhouse gas inventory accounting for the Kyoto target December Quarter 2010.’ (DCCEE, Australian National Greenhouse Accounts: Canberra)

Di HJ, Cameron KC (2006) Nitrous oxide emissions from two dairy pasture soils as affected by different rates of a fine particle suspension nitrification inhibitor, dicyandiamide. Biology and Fertility of Soils 42, 472–480.
Nitrous oxide emissions from two dairy pasture soils as affected by different rates of a fine particle suspension nitrification inhibitor, dicyandiamide.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD28XntlGhtrw%3D&md5=53d42143fb6fc179604517b10ed6d4ebCAS |

Di HJ, Cameron KC (2012) How does the application of different nitrification inhibitors affect nitrous oxide emissions and nitrate leaching from cow urine in grazed pastures? Soil Use and Management 28, 54–61.
How does the application of different nitrification inhibitors affect nitrous oxide emissions and nitrate leaching from cow urine in grazed pastures?Crossref | GoogleScholarGoogle Scholar |

Di HJ, Cameron KC, Sherlock RR (2007) Comparison of the effectiveness of a nitrification inhibitor, dicyandiamide (DCD), in reducing nitrous oxide emissions in four different soils under different climatic and management conditions. Soil Use and Management 23, 1–9.
Comparison of the effectiveness of a nitrification inhibitor, dicyandiamide (DCD), in reducing nitrous oxide emissions in four different soils under different climatic and management conditions.Crossref | GoogleScholarGoogle Scholar |

Di HJ, Cameron KC, Sherlock RR, Shen JP, He JZ, Winefield CS (2010) Nitrous oxide emissions from grazed grassland as affected by a nitrification inhibitor, dicyandiamide, and relationships with ammonia-oxidizing bacteria and archaea. Journal of Soils and Sediments 10, 943–954.
Nitrous oxide emissions from grazed grassland as affected by a nitrification inhibitor, dicyandiamide, and relationships with ammonia-oxidizing bacteria and archaea.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXntlKqt7c%3D&md5=fabbb724d0b823c1294c4a5796290492CAS |

Ding WX, Chen ZM, Yu HY, Luo JF, Yoo GY, Xiang J, Zhang HJ, Yuan JJ (2014) Nitrous oxide emission and nitrogen use efficiency in response to nitrophosphate, N-(n-butyl) thiophosphoric triamide and dicyandiamide of a wheat cultivated soil under sub-humid monsoon conditions. Biogeosciences Discussions 11, 13571–13603.
Nitrous oxide emission and nitrogen use efficiency in response to nitrophosphate, N-(n-butyl) thiophosphoric triamide and dicyandiamide of a wheat cultivated soil under sub-humid monsoon conditions.Crossref | GoogleScholarGoogle Scholar |

Eckard RJ, Chen D, White RE, Chapman DF (2003) Gaseous nitrogen loss from temperate perennial grass and clover dairy pastures in south-eastern Australia. Australian Journal of Agricultural Research 54, 561–570.
Gaseous nitrogen loss from temperate perennial grass and clover dairy pastures in south-eastern Australia.Crossref | GoogleScholarGoogle Scholar |

Fangueiro D, Fernandes A, Coutinho J, Moreira N, Trindade H (2009) Influence of two nitrification inhibitors (DCD and DMPP) on annual ryegrass yield and soil mineral N dynamics after incorporation with cattle slurry. Communications in Soil Science and Plant Analysis 40, 3387–3398.
Influence of two nitrification inhibitors (DCD and DMPP) on annual ryegrass yield and soil mineral N dynamics after incorporation with cattle slurry.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXksVyntA%3D%3D&md5=2b68ec8c016e5846918076c577cc3fafCAS |

Friedl J, Scheer C, Rowlings DW, McIntosh HV, Strazzabosco A, Warner DI, Grace PR (2016) Denitrification losses from an intensively managed sub-tropical pasture – Impact of soil moisture on the partitioning of N2 and N2O emissions. Soil Biology & Biochemistry 92, 58–66.
Denitrification losses from an intensively managed sub-tropical pasture – Impact of soil moisture on the partitioning of N2 and N2O emissions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2MXhs1Cqtb%2FP&md5=e98fb9ecc5eb6f692b381b550a1ff26bCAS |

Gilsanz C, Baez D, Misselbrook TH, Dhanoa MS, Cardenas LM (2016) Development of emission factors and efficiency of two nitrification inhibitors, DCD and DMPP. Agriculture, Ecosystems & Environment 216, 1–8.

Harris RH, Officer SJ, Hill PA, Armstrong RD, Fogarty KM, Zollinger RP, Phelan AJ, Partington DL (2013) Can nitrogen fertiliser and nitrification inhibitor management influence N2O losses from high rainfall cropping systems in South Eastern Australia? Nutrient Cycling in Agroecosystems 95, 269–285.
Can nitrogen fertiliser and nitrification inhibitor management influence N2O losses from high rainfall cropping systems in South Eastern Australia?Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXotV2ru70%3D&md5=dfcb3a9185e64759c620914c4cfd4732CAS |

Hu R, Wang XP, Pan YX, Zhang YF, Zhang H (2014) The response mechanisms of soil N mineralization under biological soil crusts to temperature and moisture in temperate desert regions. European Journal of Soil Biology 62, 66–73.
The response mechanisms of soil N mineralization under biological soil crusts to temperature and moisture in temperate desert regions.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2cXosFartLc%3D&md5=3fdacd67c85e5a11ce43d3a4e3e58d33CAS |

Huang X, Grace P, Rowlings D, Mengersen K (2013) A flexible Bayesian model for describing temporal variability of N2O emissions from an Australian pasture. The Science of the Total Environment 454–455, 206–210.
A flexible Bayesian model for describing temporal variability of N2O emissions from an Australian pasture.Crossref | GoogleScholarGoogle Scholar | 23542492PubMed |

International Fertilizer Industry Association (IFA) (2001) ‘Global estimates of gaseous emissions of NH3, NO and N2O from agricultural land.’ (IFA and Food and Agriculture Organisation (FAO): Rome)

Isbell RF (1996) ‘The Australian soil classification.’ Revised edn. (CSIRO Publishing: Melbourne)

Kawakami EM, Oosterhuis DM, Snider JL, Mozaffari M (2012) Physiological and yield responses of field-grown cotton to application of urea with the urease inhibitor NBPT and the nitrification inhibitor DCD. European Journal of Agronomy 43, 147–154.
Physiological and yield responses of field-grown cotton to application of urea with the urease inhibitor NBPT and the nitrification inhibitor DCD.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38Xht1Gmur7N&md5=1da09bc2c2b3a2530875181aff9b87ddCAS |

Kelly KB, Phillips FA, Baigent R (2008) Impact of dicyandiamide application on nitrous oxide emissions from urine patches in northern Victoria, Australia. Australian Journal of Experimental Agriculture 48, 156–159.
Impact of dicyandiamide application on nitrous oxide emissions from urine patches in northern Victoria, Australia.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1cXovVyh&md5=661475009eb8656b0ea56c81368374caCAS |

Kyveryga P, Blackmer T (2014) Probability of profitable yield response to nitrification inhibitor used with liquid swine manure on corn. Precision Agriculture 15, 133–146.
Probability of profitable yield response to nitrification inhibitor used with liquid swine manure on corn.Crossref | GoogleScholarGoogle Scholar |

Li D, Watson CJ, Yan MJ, Lalor S, Rafique R, Hyde B, Lanigan G, Richards KG, Holden NM, Humphreys J (2013a) A review of nitrous oxide mitigation by farm nitrogen management in temperate grassland-based agriculture. Journal of Environmental Management 128, 893–903.
A review of nitrous oxide mitigation by farm nitrogen management in temperate grassland-based agriculture.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXhsVWjtbrI&md5=69235b7507a46b937a90ab5d23de2555CAS | 23880433PubMed |

Li S-X, Wang Z-H, Stewart BA (2013b) Responses of crop plants to ammonium and nitrate N. In ‘Advances in agronomy’. (Ed. DL Sparks) Ch. 5, pp. 205–397. (Academic Press).

McKenzie FR, Jacobs JL, Kearney G (2003) Long-term effects of multiple applications of nitrogen fertiliser on grazed dryland perennial ryegrass/white clover dairy pastures in south-west Victoria. 2. Growth rates, dry matter consumed, and nitrogen response efficiencies. Australian Journal of Agricultural Research 54, 471–476.
Long-term effects of multiple applications of nitrogen fertiliser on grazed dryland perennial ryegrass/white clover dairy pastures in south-west Victoria. 2. Growth rates, dry matter consumed, and nitrogen response efficiencies.Crossref | GoogleScholarGoogle Scholar |

Menéndez S, Merino P, Pinto M, González-Murua C, Estavillo JM (2009) Effect of N-(n-butyl) thiophosphoric triamide and 3,4 dimethylpyrazole phosphate on gaseous emissions from grasslands under different soil water contents. Journal of Environmental Quality 38, 27–35.
Effect of N-(n-butyl) thiophosphoric triamide and 3,4 dimethylpyrazole phosphate on gaseous emissions from grasslands under different soil water contents.Crossref | GoogleScholarGoogle Scholar | 19141792PubMed |

Misselbrook TH, Cardenas LM, Camp V, Thorman RE, Williams HM, Rollett AJ, Chambers BJ (2014) An assessment of nitrification inhibitors to reduce nitrous oxide emissions from UK agriculture. Environmental Research Letters 9, 115006
An assessment of nitrification inhibitors to reduce nitrous oxide emissions from UK agriculture.Crossref | GoogleScholarGoogle Scholar |

O’Connor PJ, Hennessy D, Brophy C, O’Donovan M, Lynch MB (2012) The effect of the nitrification inhibitor dicyandiamide (DCD) on herbage production when applied at different times and rates in the autumn and winter. Agriculture, Ecosystems & Environment 152, 79–89.
The effect of the nitrification inhibitor dicyandiamide (DCD) on herbage production when applied at different times and rates in the autumn and winter.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XkvFSns7k%3D&md5=8579dbc6a095dd3f0e9ca967a270bf96CAS |

Rafique R, Anex R, Hennessy D, Kiely G (2012) What are the impacts of grazing and cutting events on the N2O dynamics in humid temperate grassland? Geoderma 181–182, 36–44.
What are the impacts of grazing and cutting events on the N2O dynamics in humid temperate grassland?Crossref | GoogleScholarGoogle Scholar |

Rawluk CDL, Grant CA, Racz GJ (2001) Ammonia volatilization from soils fertilized with urea and varying rates of urease inhibitor NBPT. Canadian Journal of Soil Science 81, 239–246.
Ammonia volatilization from soils fertilized with urea and varying rates of urease inhibitor NBPT.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD3MXlvVGqsrc%3D&md5=28fd754abc7da7993c5dedc04fa3f362CAS |

Rayment GE, Lyons DJ (2011) 7A2b Total soil-N, semi micro Kjeldahl - automated colour, FIA. In ‘Soil chemical methods – Australasia’. (Eds GE Rayment, DJ Lyons) pp. 104–108. (CSIRO Publishing: Melbourne)

Rowlings DW, Scheer C, Liu S, Grace PR (2016) Annual nitrogen dynamics and urea fertilizer recoveries from a dairy pasture using 15N; effect of nitrification inhibitor DMPP and reduced application rates. Agriculture, Ecosystems & Environment 216, 216–225.
Annual nitrogen dynamics and urea fertilizer recoveries from a dairy pasture using 15N; effect of nitrification inhibitor DMPP and reduced application rates.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC2MXhs1yjtb7K&md5=96447a2be2ec2cdc3b0046fcba10d9a5CAS |

Saggar S, Andrew RM, Tate KR, Hedley CB, Rodda NJ, Townsend JA (2004) Modelling nitrous oxide emissions from dairy-grazed pastures. Nutrient Cycling in Agroecosystems 68, 243–255.
Modelling nitrous oxide emissions from dairy-grazed pastures.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD2cXhvF2lsr8%3D&md5=bb8d0458e4c7bf55fc3d8dbfe9f9738cCAS |

Saggar S, Jha N, Deslippe J, Bolan NS, Luo J, Giltrap DL, Kim DG, Zaman M, Tillman RW (2013) Denitrification and N2O:N2 production in temperate grasslands: Processes, measurements, modelling and mitigating negative impacts. The Science of the Total Environment 465, 173–195.
Denitrification and N2O:N2 production in temperate grasslands: Processes, measurements, modelling and mitigating negative impacts.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XhvVKlt73L&md5=2ed2f15654c742395c79bc89669715e7CAS | 23260378PubMed |

Sanz-Cobena A, Sánchez-Martín L, García-Torres L, Vallejo A (2012) Gaseous emissions of N2O and NO and NO3 − leaching from urea applied with urease and nitrification inhibitors to a maize (Zea mays) crop. Agriculture, Ecosystems & Environment 149, 64–73.
Gaseous emissions of N2O and NO and NO3 leaching from urea applied with urease and nitrification inhibitors to a maize (Zea mays) crop.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC38XitlGiu7o%3D&md5=2d7194fc1c2ba4a74f292707cc48eeeeCAS |

Singh J, Kunhikrishnan A, Bolan NS, Saggar S (2013) Impact of urease inhibitor on ammonia and nitrous oxide emissions from temperate pasture soil cores receiving urea fertilizer and cattle urine. The Science of the Total Environment 465, 56–63.
Impact of urease inhibitor on ammonia and nitrous oxide emissions from temperate pasture soil cores receiving urea fertilizer and cattle urine.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXjsFygsb4%3D&md5=8d63b3b9a5eb463ccf833f8dc11e6f91CAS | 23473618PubMed |

Skalar Analytical B.V. (2005) ‘The SANplus segmented flow analyser: soil and plant analysis.’ (Skalar Analytical B.V.: Netherlands).

Suter HC, Sultana H, Turner DA, Davies R, Walker C, Chen D (2013) Influence of urea fertiliser formulation, urease inhibitor and season on ammonia loss from ryegrass. Nutrient Cycling in Agroecosystems 95, 175–185.
Influence of urea fertiliser formulation, urease inhibitor and season on ammonia loss from ryegrass.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXotV2qsrs%3D&md5=40e8195f3535700e0b7bc491dc38928aCAS |

Turner DA, Edis RB, Chen D, Freney JR, Denmead OT, Christie R (2010) Determination and mitigation of ammonia loss from urea applied to winter wheat with N-(n-butyl) thiophosphorictriamide. Agriculture, Ecosystems & Environment 137, 261–266.
Determination and mitigation of ammonia loss from urea applied to winter wheat with N-(n-butyl) thiophosphorictriamide.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3cXltFOms7k%3D&md5=d6b1cfdc9688ec61f49372905b72edc7CAS |

Venterea RT, Parkin TB, Cardenas L, Petersen SO, Pedersen AR (2012) Data analysis considerations. In ‘Nitrous oxide chamber methodology guidelines version 1’. (Eds CAM de Klein, MJ Harvey) pp. 95–121. (Ministry for Primary Industries: New Zealand)

Watson CJ, Stevens RJ, Laughlin RJ (1990) Effectiveness of the urease inhibitor NBPT (N-(n-butyl) thiophosphoric triamide) for improving the efficiency of urea for ryegrass production. Fertilizer Research 24, 11–15.
Effectiveness of the urease inhibitor NBPT (N-(n-butyl) thiophosphoric triamide) for improving the efficiency of urea for ryegrass production.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaK3MXhtVSgur0%3D&md5=8aa2ea451e5aad250b3fd332c47b59e0CAS |

Yeomans JC, Bremner JM (1986) Effects of urease inhibitors on denitrification in soil. Communications in Soil Science and Plant Analysis 17, 63–73.
Effects of urease inhibitors on denitrification in soil.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DyaL28Xhs1OnurY%3D&md5=5780b13cf7a1ca49f62fba3e5ef88f9cCAS |

Zaman M, Saggar S, Blennerhassett JD, Singh J (2009) Effect of urease and nitrification inhibitors on N transformation, gaseous emissions of ammonia and nitrous oxide, pasture yield and N uptake in grazed pasture system. Soil Biology & Biochemistry 41, 1270–1280.
Effect of urease and nitrification inhibitors on N transformation, gaseous emissions of ammonia and nitrous oxide, pasture yield and N uptake in grazed pasture system.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BD1MXmtVGkur0%3D&md5=c5d7fdefaa7b8b225149bc11d4d8d361CAS |

Zaman M, Zaman S, Adhinarayanan C, Nguyen ML, Nawaz S, Dawar KM (2013) Effects of urease and nitrification inhibitors on the efficient use of urea for pastoral systems. Soil Science and Plant Nutrition 59, 649–659.
Effects of urease and nitrification inhibitors on the efficient use of urea for pastoral systems.Crossref | GoogleScholarGoogle Scholar | 1:CAS:528:DC%2BC3sXhtlansr7E&md5=9dac0b9659910604c3c3aeaad1d4ccb1CAS |

Zhengping W, Liantie L, Van Cleemput O, Baert L (1991) Effect of urease inhibitors on denitrification in soil. Soil Use and Management 7, 230–233.
Effect of urease inhibitors on denitrification in soil.Crossref | GoogleScholarGoogle Scholar |