Reaction of oriental tobacco to spacing and topping treatments at three levels of nitrogenous fertilizer application

Abstract

Three levels of nitrogenous fertilizer were applied to oriental tobacco (Nicotiana tabacum L. cv. Elcatra) at different spacings and topped to 14 and 28 leaves per plant respectively. Yield, income, total nitrogen and total alkaloids of the cured leaves increased, and total reducing sugars decreased as nitrogen application was increased. Acceptable levels of quality attributes such as total nitrogen, alkaloids, and reducing sugars, as well as a high income, were obtained when plants were spaced 20 cm from each other in 25 cm twin rows with an interrow space of 50 cm, topped to 28 leaves and fertilized with a high level of N (72 kg N ha⁻¹).