This trial was conducted at foot slope (Lower Elevation) of the field located in Minnehaha county. Soybeans were planted on June 10, 2019 at 160,000 seeds/acre in 30-inch rows. Two treatment for this experiment were Nitrogen with sulfur fertilizer and Nitrogen without sulfur fertilizer. For Nitrogen with sulfur, nitrogen and sulfur fertilizer were mixed at the rate of 30 lb/ac and 15 lb/ac respectively and applied at R3 growth stage, whereas for nitrogen without sulfur treatment, solely nitrogen fertilizer was applied at the rate of 30 lb/ ac at same time. Fertilizer source for nitrogen and sulfur fertilizer were polymer coated urea and ammonium sulfate respectively. Both fertilizer treatments had four replications. Plot size for this experiment was 10 feet wide and 30 feet long. For the data analysis to quantify the effect of sulfur on soybean yield, combined application of nitrogen and sulfur treatment was subtracted with nitrogen treatment.
Overall, at foot slope of the field, nitrogen with sulfur increase the yields by 0.26 bu/ac, however it was not statistically significant (Table 1). Rep, 1 had an increase in yield by 8.27 bu/ac compared to due to combined effect of Nitrogen and sulfur fertilizer, whereas Rep 2, 3 and 4 had reduced yield. Additional trials with more replications should be completed to identify efficacy of treatment over multiple years.