Submitted to: Agronomy Journal
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/17/2014
Publication Date: 3/1/2014
Publication URL: http://handle.nal.usda.gov/10113/5491325
Citation: Watts, D.B., Runion, G.B., Smith Nannenga, K.E., Torbert III, H.A. 2014. Enhanced-efficiency fertilizer effects on cotton yield and quality in the Coastal Plains. Agronomy Journal. 106:745-752. doi:10.2134/agronj13.0216
Interpretive Summary: Interest in the use of new commercially available controlled and slow released N fertilizers, also known as enhanced efficiency N fertilizers, has increased within the last decade. These fertilizer sources are believed to increase N uptake in agricultural crops by synchronizing N release with plant growth. Thus, a study was conducted to determine if these new fertilizer sources could increase cotton yield and fiber quality compared to traditional fertilizer sources. Nitrogen sources evaluated included urea, ammonium sulfate, urea-ammonium sulfate, a controlled release polymer coated urea (Environmentally Smart Nitrogen; ESN), stabilized urea containing a urease and a nitrification inhibitor (Super Urea), poultry litter, poultry litter + a urease and a nitrification inhibitor (AgrotainPlus), and an unfertilized control. Generally, the slow and controlled released fertilizers produced similar cotton yields to that of the traditional fertilizer sources. Some differences in cotton fiber quality were observed among the fertilizer sources; however, differences were not enough to impact discount/premium values.
Technical Abstract: Interest in the use of enhanced-efficiency N fertilizer (EENFs) sources has increased in recent years due to the potential of these new EENF sources to increase crop yield, while at the same time decreasing N loss from agricultural fields. The efficacy of these fertilizer sources on cotton production in Southeastern US upland soils has not been well documented. Thus, a field study was conducted on a Coastal Plain soil (Marvyn loamy sand; fine-loamy, kaolinitic, thermic Typic Kanhapludult) in Central Alabama from 2009 to 2011 to compare EENFs to traditional N sources in a high-residue conservation cotton production system. Nitrogen fertilizer sources evaluated included urea, ammonia sulfate, urea-ammonia sulfate, controlled-release, polymer-coated urea (ESN), stabilized urea (SuperU), poultry litter, poultry litter + AgrotainPlus, and an unfertilized control. Generally, no significant differences in yield were observed between the traditional sources and EENFs. Nitrogen source affected fiber quality; however, effects varied among years and generally would not have impacted discount/premium values. In the present study, EENFs produced yields similar to conventional fertilizers, suggesting their higher cost may render them impractical at present. However, if EENFs reduce N loss through leaching, runoff and N2O flux from agricultural fields they could become viable alternative fertilizer sources. More research is needed on the benefits of enhanced efficiency fertilizer use as a tool in production systems.