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

16 Feb 2013

2012 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 a nitrification inhibitors) at 45, 90 and 135 kg N/ha. All N treatments are side-banded at planting of the crops and in the spring. The experiments were conducted on spring wheat, barley and canola. The study was initiated in April 2008, and repeated in 2009 through 2012.

In 2012, the three annually seeded crops grew well due to adequate spring and early summer precipitation. However, warmer temperatures in early July, plus drier than normal weather conditions in late July and August was hard on canola flowering, seed set, and yield. Much of the canola growing area of the Northern Great Plains (NGP) region reported disappointing canola yields due to so called "flower blasting" reducing potential yields. Vegetative growth would have indicated average to above average yields but loss of viable and fertilized flowers significantly reduced yields. The barley and canola crops both showed a significant but modest response to added N, while the spring wheat crop didn't. The moist early summer conditions and warm temperatures during early July probably resulted in a greater than normal mineralization of N from soil organic matter. N response in previous years of this study was greater. In 2012, there were little differences observed for all three crops as far as the form of N applied. Regular urea, Nutrisphere treated urea and Super Urea all showed similar yields. The modest or low response to N contributed to a challenge in observing differences between forms of N, and any possible form of N and N rate interactions. Also growing conditions were not conducive to leaching or denitrification losses that may have resulted in greater yields for the Nutrisphere treated urea and the Super Urea, compared to regular urea. The five years of results from this research will be grouped together and analyzed. A final project report will be completed in later 2013. SK-40F