Project title: Starter fertilizer for corn and sorghum production under no-till conditions

Principal investigator:

Charles Wortmann

Martha Mamo

Duration: 2002 to 2004

Funding: INTSORMIL; Performance Polymers

Contact:

Charles Wortmann Department of Agronomy and Horticulture, UNL, 154 Keim Hall, Lincoln NE 68583-0915, (402)472-2909 cwortmann2@unl.edu

Martha Mamo Department of Agronomy and Horticulture, UNL, 242 Keim Hall, Lincoln NE 68583-0915, (402)472-8493

Charles Shapiro Northeast Research and Extension Center, Haskell Agricultural Laboratory, UNL, 57905 866 Road, Concord, NE 68728-2828, (402)584-2803, cshapiro1@unl.edu

Project description:

Results of research conducted in NE show that use of starter fertilizer for corn and sorghum production is not profitable on fine-textured soils. However, results from neighboring states show a high probability of response to N+P and N+P+S starter fertilizer under no-till conditions on some soil types. The objective of this research is to determine the conditions under which use of starter fertilizers is profitable for no-till production in eastern Nebraska.

Beginning in 2002, on-farm trials of four replications are being conducted in eastern NE across diverse soil types and topographic positions. There are eight treatments: no starter applied; N+P applied 2x2 at 20 + 20 lb; N+P applied over the row at 20 + 20 lb; N+P applied in the furrow at 10 + 10 lb; N+P+S applied 2x2 at 20 + 20 + 10 lb; N+P+S applied over the row at 20 + 20 + 10 lb; N+P+S applied in the furrow at 10 + 10 + 5 lb; and N+P+S applied in the furrow at 10 + 10 + 5 lb but with sulfur supplied from ammonium thiosulfate rather than ammonium sulfate as in the other treatments with sulfur.

Key results:

Six sorghum trials were conducted in 2002 in Gage county. The average yield was 99 bu/A but there was no effect of starter fertilizer on yield in any of these trials. Five dryland corn trials were conducted with no response to starter fertilizer. Three of these were severely constrained by water deficits and two were less constrained with respective average yields of 46 and 111 bu/A. There was not a significant response to starter fertilizer in an irrigated corn trial.