Research on AGROTAIN® was completed on small-plot trials. The majority of studies did not report sufficient information about environmental conditions and practices to enable a full assessment of the nutrient use efficiency benefits possible from using AGROTAIN®, therefore we report results that suggest the effectiveness of AGROTAIN® based on yield only.
The intent of the NutrientStar program is to assess whether nitrogen stabilizers and decision support tools improve nutrient use efficiency (NUE). However, few of the trials applied more than one nitrogen rate, which prevented the calculation of NUE. NutrientStar also attempted to analyze the results of trials based on rainfall, but because few of the trials reported daily rainfall after nitrogen application, we were unable to do so, and the yield results were averaged across all the trials.
NutrientStar would be better able to assess the conditions where AGROTAIN® might be effective as a stabilizer if rainfall data had been provided. This analysis would involve separating the trials into two categories: those where sufficient rainfall occurred within two days of application of AGROTAIN® to wash the fertilizer into the soil, which would greatly reduce the chance of AGROTAIN® improving NUE, and those where little to no rainfall occurred for two or more days after application, which would greatly enhance the chances of AGROTAIN® improving NUE.
The NutrientStar program is committed to promulgating common standards for research and minimal data requirements that will allow products and tools to be fully assessed for their ability to improve NUE in the future. Information about protocols required to fully assess products and tools is available here.

AGROTAIN®, made by Koch Agronomic Services, is used to treat dry and liquid nitrogen fertilizers to slow the conversion of urea to ammonia gas. Slowing the conversion of urea to ammonia should decrease losses of nitrogen to the atmosphere.
AGROTAIN® has the potential to decrease nitrogen losses only when urea is applied to the soil surface. Injection or incorporation of urea into the soil will cause the urea to convert to ammonia in the soil where there will be sufficient moisture to immediately change the ammonia to ammonium, which is not a gas and is held tightly to the soil.

Product Description and Mode of Action

AGROTAIN® is an additive targeted to fertilizers that contain urea. The purpose of AGROTAIN® is to reduce ammonia volatilization after fertilizer application. The active ingredient, NBPT, functions as a urease inhibitor. Urease inhibitors reduce the speed of conversion from urea in fertilizer to ammonium (enzymatic hydrolysis), which can then either rapidly convert to gaseous ammonia and be lost to the air or convert to nitrate (NO3-) and be subject to leaching losses. By staying longer in the urea form, the fertilizer can more slowly become available to plants, increasing the chance of being there when needed by the crop (Trenkel 1997).


AGROTAIN® is for use with all crops to reduce ammonia volatilization.


Farmers who wish to increase NUE by reducing ammonia volatilization.


Varies based on volume.


AGROTAIN® is a urea fertilizer additive.

Research Results from Field-Scale Strip Trials

NutrientStar reviewers found no published research results from field scale strip trials.

Research Results from Chemistry Trials

Note: Chemistry trials can provide information concerning the effectiveness of a product in laboratory and greenhouse settings but do not provide information related to a products effectiveness in the field.
NBPT, the active ingredient in AGROTAIN®, was identified in early laboratory studies to be a good repressor of urea hydrolysis, even when applied at low concentrations (Beyrouty et al. 1988; Bremner and Chai 1986; Hendrickson and Douglass 1993; Watson et al. 1994).

Research Results from Small Plots

An intensive and extensive review of the literature was completed to assess the effectiveness of AGROTAIN® PLUS to increase yield of corn and wheat. All the research was completed on small plots. Typical plot dimensions were 15 feet wide by 40 feet long, and although plot sizes varied, none were greater than 1/2 acre in size.


The average yield increase measured for AGROTAIN® when AGROTAIN®-treated granular urea or liquid urea ammonia nitrate (UAN) was compared with non-treated urea or UAN was 10 bushel/acre, with a 95% confidence interval of 7 to 13 bu/acre..


The average yield increase measured for AGROTAIN® when AGROTAIN®-treated granular urea or liquid urea ammonia nitrate (UAN) was compared with non-treated urea or UAN was 3 bushel/acre, with a 95% chance of obtaining a yield increase of 1 to 5 bu/acre.

For more information about small plot results on the effectiveness of AGROTAIN® to increase yield please visit our summary page.