Zinc and Sulfur Fertilization for High-Yield Corn Production
Study author(s): Jeffrey Vetsch, University of Minnesota, Southern Research and Outreach Center
Years of study: 2008 – 2010
Location(s): Mower County, Goodhue County, and Lamberton, MN
Important: for the complete report, including all tables and figures, please download using the link(s) to the right.
SUMMARY
Five gal/A of APP applied in-furrow (pop-up) increased grain yields at 3 of 9 sites and averaged 4 bu/A across sites on these high and very high P testing soils. Five gal/A of APP + 2 gal/A of ATS applied as a surface band increased yield and economic return at 3 of 9 sites, compared with 5 gal/A of APP applied in-furrow. Averaged across sites, yields were increased 5 bu/A and economic return $16/A. The addition of 1 qt/A of chelated Zn (0.25 lb Zn/A) to 5 gal/A of APP increased corn yield and economic return at 2 of 9 sites (when compared with 10-34-0 alone) and reduced yield and return at 2 of 9 sites. However in only of 1 of 9 sites did the addition of chelated Zn to APP increase yields above the control. A response to chelated Zn was found in 1 of 3 sites that had a soil test DTPA-Zn of 0.4 ppm (in the responsive range which is < 0.76 ppm, based on current Univ. of Minnesota recommendations). Yields and economic returns were increased 6 bu/A and $13/A above the control with the 15 lb/A rate of ZnSO4, when averaged across sites. However, some of the response to this treatment was attributed to S. In this research study corn yield responses to Zn fertilization were rare and small when they did occur.