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

IPNI-1990-USA-MD6

23 Mar 2009

2008 Annual Interpretive Summary

Building a Maximum Yield Cropping System for Corn, Wheat, and Doublecropped Soybeans in Maryland, 2008

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 2008 again confirmed that blends containing an amount of AS sufficient to supply 30 lb/A of S, whether applied pre-plant or sidedressed at the six-leaf stage, produced corn yields as high as or better than those achieved with granular urea or liquid urea-ammonium nitrate (UAN). Despite a drought year, these blends produced corn yields of around 130 bu/A with a total application of 130 lb/A of N. Under zone tillage, corn yielded up to 147 bu/A with only 120 lb/A of N applied. Two products designed to enhance N use efficiency increased yields slightly at a normal N rate, but did not make up for yield losses caused by a 25% reduction in N rate. MD-06F