Building a Maximum Yield Cropping System for Corn, Wheat and Double-cropped Soybeans

IPNI-1990-USA-MD6

23 Feb 2011

2010 Annual Interpretive Summary

Building a Maximum Yield Cropping System for Corn, Wheat, and Doublecropped Soybeans, 2010

The goal of this study is to develop a management program that increases crop yield, input efficiency, and profit potential in a predominantly no-till cropping system. This cropping system consists of four crops planted over 3 years, including: no-till soybeans in corn stubble, followed by minimum-till wheat doublecropped with no-till soybeans, and then no-till corn.

In research on the Eastern Shore of Maryland, N use efficiency in corn and wheat has improved when ammonium sulfate (AS) was blended with either urea or ammonium nitrate (AN). Research in 2009 again confirmed that blends containing an amount of AS sufficient to supply 30 lb/A of S produced corn yields higher than those achieved with granular urea applied pre-plant. Despite a drought year, these blends produced corn yields of around 120 bu/A with a total application of 120 lb/A of N. Blends of ammonium nitrate with ammonium sulfate and urea produced yields as high as those with ammonium sulfate and urea in no-till and higher than those with ammonium sulfate and urea in strip-till.

In 2010, several N sources improved yields of no-till corn relative to broadcast granular urea. These sources included polymer-coated urea, partial blends including ammonium sulfate, urease inhibitors and other materials. Several of these same sources nudged yields to over 200 bu/A in on-farm trials near Baltimore. Comparison of 16 different N sources for wheat showed large effects (9 bu/A) of including AS in the blend and a statistically significant 5 bu/A yield boost from the Nutrisphere product. These trials have generated enthusiasm among producers for continued testing of practices to improve N use efficiency. MD-06F