Evaluation of Urea Nitrogen Fertilizer Treated with Nutrisphere Polymer Additive to Increase Fertilizer Efficiency

The use of polymer additives to regular soluble fertilizers has been shown to increase the uptake of fertilizer nutrients into target crops. The mechanism of activity of the polymers is thought to slow down the reaction of the fertilizer nutrient ions and molecules with various soil compounds. The Nutrisphere polymer additive is added to urea or urea containing nitrogen fertilizers.

IPNI-2008-CAN-SK40

03 Mar 2012

2011 Annual Interpretive Summary


This project, at the Indian Head Research Farm near Indian Head, Saskatchewan, consists of three experiments comparing regular granular urea, urea treated with Nutrisphere-N® (a polymer coating), and Super Urea® (including both urease and nitrification inhibitors) at 45, 90, and 135 kg N/ha. The experiments were conducted on spring wheat, barley, and canola. The study was initiated in April 2008, and repeated in 2009, 2010, and 2011. In 2011, growing conditions were cool and more moist than normal, early in the growing season, and drier and warmer than normal in the last half of the growing season.

A significant response to N was observed for all three crops. There was a slight overall yield benefit to the slow release N products observed with canola, but not for wheat or barley. It is thought that the soil conditions susceptible for denitrification losses were met at Indian Head from late May through June which could have increased the potential for a benefit to the side-banded Super-U and NSN, but at least for the barley, yields were limited more by the excess spring moisture than by N. Both the wheat and the canola ended up yielding well and the response to N for both crops was quite linear up to 134 kg N/ha. The conditions suitable for denitrification losses are not experienced very often in this area of Saskatchewan, but it does demonstrate the potential benefits of these enhanced urea products when the potential for N loss is high. SK-40F