2022 journal article
Flue‐cured tobacco and Cl rates: Implications on yield, quality, and nutrient concentration
Agronomy Journal.
AbstractThe increase in flue‐cured tobacco (Nicotiana tabacum L.) yields in recent decades due to genetic improvements of new cultivars and management technologies may increase the plant demand for Cl, and the increased dry mass may dilute Cl concentration, thereby reducing negative effects. This study evaluated the effect of increasing doses of Cl on tobacco production, quality, and chemical composition of leaves, in four growing environments located at research stations where flue‐cured tobacco is produced in North Carolina. The treatments consisted of 11 rates of Cl (0, 11, 22, 34, 45, 56, 67, 78, 90, 101, and 112 kg ha−1) in each growing environment, with four replications in a randomized complete block design. The yield and visual quality, total alkaloids, and reducing sugars concentrations of cured leaf were determined. In addition, the concentration of selected nutrients (N, P, K, Ca, Mg, S, and Cl) and nitrate (NO3−) in tobacco leaves was measured in five different periods. Rates of Cl up to 112 kg ha−1 did not reduce the productivity or quality of flue‐cured tobacco in any environment. The Cl rate required to reach the threshold of 1.0% Cl content in cured leaf was site‐specific, being surpassed even in the control treatment at one location, or with Cl rates higher than 34 and 90 kg ha−1 in two environments. In one environment, the Cl rates increased tobacco yield, probably due the direct effect of Cl as a nutrient. Although the increasing Cl rates increased the reducing sugars concentration, visual quality was not attenuated.