2006 Annual Report: Effect of Nitrogen Application Timing, Dry Sources and Rates on No-till Corn Yields
The supply of ammonium nitrate is decreasing and more urea production capacity is being built overseas. The goal is to determine the impact of changing nitrogen sources from ammonium nitrate to urea in NW Missouri.
Methods and Materials
|Planting Date||April 17||Herbicides||PRE Glyphosate + Dual + Atrazine + Callisto; Post Accent + Clarity|
|Hybrid||Pioneer 31G68||Insecticides||Lorsban Banded 8oz/1000ft|
Ammonium nitrate, Urea and Urea + Agrotain was applied at March, April and May application dates and each with 5 different nitrogen application rates. The plots were established following a previous soybean crop.
There was no statistically significant difference between the application dates in 2006 and 2005. However, research indicates the nearer the time of application to the time when the corn crop will utilize it for growth, the less risk there is for loss.
|Nitrogen Application Timing|
|2005 Application Dates||Corn Yield (bu/a)||2006 Application Dates||Corn Yield (bu/a)|
|LSD0.05 = 17||LSD0.05 = 7|
There was a statistically significant difference between ammonium nitrate and urea applied with Agrotain. However, research by Dr. Scharf, Extension Soil Fertility Associate Professor, would recommend the use of Agrotain with urea when top-dressed in no-till.
|Dry Nitrogen Fertilizer Sources|
|Fertilizer Source||2005 Yield (bu/a)||2006 Yield (bu/a)|
|Urea + Agrotain||178|
|LSD0.05 = 7||LSD0.05 = 7|
Means with the same letter are not significantly different.
|Effect of Nitrogen Rates on Corn Yield|
|Nitrogen Rates (lbs/a)||2005 Yields (bu/a)||2006 Yield (bu/a)|
|LSD0.05 = 10||LSD0.05 = 9|