2010 Evaluation of Dark Tobacco at Murray State University: Study 3: (Paschall, Stuard, and Vowell) The Impact of Various Side-dress Nitrogen Sources on Dark-fired Tobacco Growth and Yield

Nitrogen (N) is the primary nutrient for tobacco growth and production. To improve the N fertilizer efficiency, side-dress applications have to be used during the vegetative growing season. This method will yield better return on investment compared to one time N application. Therefore, the purpose of this study was to evaluate the effect of different side-dress N sources on the growth and yield of dark-fired tobacco after transplanting. The variety used was PD7318 dark-fired tobacco. The tobacco was transplanted on June 15, 2010. There were seven treatments used in the experiment with all treatments receiving 150lbs N/acre of side-dress nitrogen. All treatments received 150 lbs N/acre from urea + DAP prior to transplanting. Phosphorus and K fertilizers were applied prior to transplanting based on soil recommendations. The side-dress N sources were: control (no N side-dress application), Sulfur N-26, 50:50 blend of N-26+urea, NH4NO3, UAN, UCAN-21 and KNO3. All the N sources were applied on July 9, 2010, except for UAN that was applied on July 13, 2010. Each treatment had four replications and the plot was four rows wide. The tobacco was harvested September 22 to October 6, 2010