The geographic framework shown here delineates spatial units with shared soil and climatic properties, where one might expect agronomic tools and/or products to perform similarly if all other farm management variables are constant. AGROTAIN® trials conducted using urea, UAN or both are super-imposed on the framework, which we refer to as Technology Extrapolation Domains or TEDs.

AGROTAIN® Trial Locations and the TED Framework

To better understand the climate and soil conditions under which these trials were performed please visit the TED framework page. There you will find the climate and soil conditions associated with each six digit TED (Technology Extrapolation Domain) as well as other areas that share those conditions.

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.


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® 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.

Summary of Evidence


Four separate studies testing AGROTAIN® reported significant increases in corn yield. However, while results of a number of the many individual studies were inconclusive, when all studies are considered together AGROTAIN® significantly increased yield. Average increases in corn yield of between 7% and 14% can be anticipated within the regions for which data are available.


For wheat, the overall weighted effect size for AGROTAIN® is significantly affected by very positive results from one study in Saskatchewan (Malhi et al. 2003), for which the strong yield impact was caused by poor seed emergence due to seed-row placement of the urea fertilizer. In this case, the benefit was not necessarily due to improved N use efficiency but the coating of the fertilizer, as less seedling damage with the AGROTAIN®-coated urea fertilizer enhanced crop establishment. This illustrates the importance of looking carefully at the results of individual studies, or at least at considering whether studies should be included in meta-analysis as representative of the typical product use. Therefore, the positive yield impact of AGROTAIN® for wheat should be approached with some caution, and further data collection would be beneficial.

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