Urease and Nitrification Inhibitors Impact on Winter Wheat Fertilizer Timing, Yield, and Protein Content
- Mohammed, Yesuf Assen [ Montana State University: Research Centers ]
- Chen, Chengci [ Montana State University: Research Centers ]
- Jensen, Tom [ International Plant Nutrition Institute 104-110 Research Drive, Canada ]
Nitrogen fertilizer is an important input for winter wheat (Triticum aestivium L.) production. However, the losses of applied N fertilizer are economically substantial and environmentally unsafe. Therefore, improved N fertilizer management practices are needed to increase yield, enhance wheat quality, and minimize negative consequences to the environment. The objective of this experiment was to determine the impact on two N fertilizer sources, two application times, and three placement methods on grain yield, protein concentration, and N uptake of winter wheat. The experiment was conducted in Montana, in a randomized complete block design. The mean grain yield, protein concentration, and N uptake in 2010/2011 were lower than 2012/2013 due to differences in soil fertility and inter-seasonal variations in precipitation. Treatment effects were significant in 2010/2011 (wet season) but not in 2012/2013 (dry season). In 2010/2011, urea with agrotain (urease inhibitor) and N serve (nitrification inhibitor) broadcasted in spring (UANSBS) produced the highest yield (2630 kg ha–1). This yield increase was 29% more than fall applied urea. In 2010/2011, spring broadcasting of urea, urea with agrotain, Super Urea (urea with urease and nitrification inhibitors), and UANSBS produced similar but higher yield, grain protein concentration and grain N uptake than other treatments. Therefore, considering the erratic nature of precipitation in this dry land area, spring broadcasting of urea with or without inhibitors appeared to be practical N fertilizer management practices for the region. But economic analysis is needed to justify this suggestion.