Effect of Nitrification Inhibitors on Nitrogen Utilization Efficiency in Sweet Corn

Abstract

A field experiment using subsurface drip irrigation was conducted at the Maricopa Agricultural Center on a Casa Grande sandy loam soil to evaluate the effect of varying nitrogen (N) sources on the growth and yield of 'Sweetie' 82' sweet corn when applied with, and without four nitrification inhibitors (Nl). The NI treatments included nitrapyrin (N-Serve*), dicyandiamide (DCD), ammonium thiosulfate, and N-Hib Calcium™. Nitrogen was supplied as urea -ammonium nitrate (UAN -32). In addition, an all nitrate source plus a control which received no added N were used. Al! N treated plots received a total of 111 lbs. N acre in split applications at the V3, V6 and the V12 stages. All solutions were applied through buried, perforated PVC tubing to simulate application through the buried drip irrigation system. The inclusion of the nitrification inhibitors with UAN-32 had no significant effect on marketable ear yield, total N uptake or nitrogen use efficiency.