48th TWC, Tob. Work. Conf., 2018, abstr. 07

The effect of chloride application rate to the yield, quality, and chemistry of flue-cured tobacco

North Carolina State University, Raleigh NC USA

Applications of chloride (Cl-) to tobacco are generally discouraged due to the negative effects the anion can have to yield, quality, and smoke flavor/aroma. Despite the negative effects associated with Cl- application, unintentional applications of the nutrient sometimes occur. The season-long implications of Cl- are not well known. Research was conducted in North Carolina to evaluate the impact of four Cl- application rates (0, 33.6, 67.3, and 100.9 kg Cl- /ha) when liquid urea-ammonium-nitrate was used as the sole source of applied nitrogen. Tissue samples were collected at five growth stages: two weeks after fertilizer application, at layby, two weeks after layby, at topping, and after curing. Leaf Cl- concentration increased with application rate, with the 67.3 and 100.9 kg rates typically being greater than the 1% threshold established by industry. Despite high Cl- application rates, toxicity symptoms were not observed, thus indicating that visual symptoms of excessive Cl- cannot be solely relied upon to determine if misapplication has occurred. Leaf yield, quality, and value were not affected by Cl- application; although, it is probable that smoke flavor and aroma may be negatively impacted at application rates greater than 33.6 kg Cl- /ha. (Reprinted with permission)