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. NutriSphere® trials conducted using urea or UAN are super-imposed on the framework, which we refer to as Technology Extrapolation Domains or TEDs.
To better understand the climate and soils 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.
NutriSphere-N® (also known as NutriSphere-N® Nitrogen Fertilizer Manager, or N-N) is a polymer-based, enhanced-efficiency fertilizer product made and distributed by Verdesian Life Sciences that can be combined with various N fertilizer sources. It can be coated onto granular fertilizers like urea, or injected into UAN solutions. Like many enhanced efficiency fertilizers, NutriSphere-N® is advertised to improve crop consumption and increase yield by decreasing the rates of nitrogen loss via volatilization, leaching, and denitrification through suppression of urease and nitrification activity. NutriSphere-N® is a relatively new enhanced-efficiency fertilizer product, but it has been tested in the laboratory and a variety of North American field locations since the early 2000s. It has also used by farmers on over 30 million acres in 40 states (Verdesian 2015).
NutriSphere-N® is intended for use with all crops for decreasing nitrogen loss.
Farmers who wish to increase NUE by reducing nitrogen losses.
Varies based on volume.
NutriSphere-N® is a polymer product that is applied to granular fertilizers or UAN solutions
NutrientStar reviewers found no published research results from field scale strip trials.
Laboratory results are mixed. The NutriSphere-N® polymer was evaluated in early laboratory experiments on jackbean at the University of Kentucky, where it was shown to inhibit nitrification as well as urease activity, with the amount of inhibition ranging from 22 to 46% (Coyne 2009). Following other laboratory experiments in North Dakota and Arkansas, Franzen et al. (2011) concluded that NutriSphere-N® had “no nitrification or urea volatilization inhibiting properties”. Some of the same researchers continued laboratory work, and found that NutriSphere-N® did reduce ammonia volatilization from UAN fertilizer, but with a much lower efficacy than ammonium thiosulfate, NBPT, and calcium thiosulfate (11%, compared to 40%, 51%, and 40%, respectively) (Goos 2013a). The same research lab found very little urease inhibition from NutriSphere-N® (it depended on the rate, at high rates of 500 mg/kg, there was some inhibition, but not nearly as much as with NBPT) (Goos 2013b).
An intensive and extensive review of the literature was completed to assess the effectiveness of NutriSphere-N® to increase corn yields. All the research was completed on small plots, with none greater than 1/10 of an acre.
The 14 plot studies averaged yield gains of 8 bushels/acre, with a confidence interval range of 2 to 14 bu/acre.
With the data available, and in the conditions studied, NutriSphere-N® failed to improve crop yield in a consistent manner particularly for wheat, even though certain studies found it to be promising. Even with some indication of yield benefits for grain corn, and because of the lack of studies testing N losses, the available data are too limited to conclude that this product improves yield across the board or provides other significant improvements in N efficiency. Therefore, if the product is to be considered further for such purposes and there is any expectation of effectiveness under specific conditions, proof of such is needed. This would require more data collection.
For more information about small plot results on the effectiveness of NutriSphere-N® to increase yield please visit our Research Findings Page.