Influence of Foliar Sulfur, Chloride and Nitrogen on Winter Wheat GRAIN YIELD and TOTAL Nitrogen.

Optimum use of nitrogen (N) is a key component in improving wheat grain yield and quality. The combined effect of other nutrients with N can have a positive impact on crop production. Using sulfur (S) and chloride (Cl) in wheat and other cereals has received increased attention in recent years.  Foliar S and Cl can assist in optimizing wheat yield and total N, especially in sandy soils with low organic matter where deficiencies are expected. Winter wheat studies were conducted at Lake Carl Blackwell (LCB) and Lahoma (LAH) in the fall of 2011 and 2012 to evaluate the effect of flag leaf applied foliar N, S and Cl on winter wheat grain yield and grain N. Two N rates, 10 and 20 kg N ha^-1, as urea triazone (N-SURE, 28-0-0) and urea ammonium nitrate (UAN, 28-0-0) were foliar applied. Treatments included foliar application of gypsum (6 kg S ha^-1) and calcium chloride at a rate of 10 kg Cl ha^-1applied using a CO₂ backpack sprayer.  Results showed total grain N increased with increasing preplant N rate at LCB and LAH. With increasing preplant N, a linear increase in yield was observed at LAH and a quadratic increase in yield at LCB. There was no response to foliar N, S at both locations. Chloride response was found at Lahoma only. For the environments evaluated foliar S fertilization did not increase grain yield and/or protein.