INFLUENCE OF NITROGEN, PHOSPHORUS, POTASSIUM, AND MAGNESIUM ON THE PHENOLIC CONSTITUENTS OF FLUE-CURED TOBACCO

Abstract

A field experiment was conducted in 1974 and 1975 on Fox loamy sand to study the effects of different rates (0,22.4, 44.8, and 67.2 kg/ha) of N fertilization on selected chemical constituents of flue-cured tobacco (Nicotiana tabacum L. cv. Delhi 34). Nitrogen fertilization increased the levels of total alkaloids, total N, and scopoletin in cured leaf. Chlorogenic acid, neo-chlorogenic acid, 4-caffeoylquinic acid, rutin, and scopolin were found to be inversely related to the rate of nitrogen. Phenolic constituents and inorganic nutrients in the leaves and inorganic nutrients in the soil (Fox loamy sand) were studied in 1975 and 1976 in another field experiment. Treatments included selected omissions of P, K, or Mg from field plots grown continuously with tobacco since 1967. Marked nutrient deficiency symptoms were observed only in plots in which K had been omitted. Tobacco from these plots was generally lower in phenolic constituents.