Abstract
A study on the influence of different forms of N fertilization on alkaloid concentration of fluecured tobacco (Nicotiana tabacum L.) was carried out for three consecutive years in Portugal. The three N fertilization treatments were 100% NO3-, 50% NO3- + 50% NH4+, and 100% NH4+ each applied at the rate of 45 kg N ha-1. In order to prevent the formation of nitrosamines, the tobacco leaves were treated with antioxidants. Before harvesting, the leaves were individually sprayed with solutions containing different proportions of ascorbic acid and ?-tocopherol. The determination of individual alkaloids (nicotine, nornicotine, anabasine, anatabine, and 2,3’- bipyridyl) on the treated leaves, after cure, was done by a High Resolution Gas Chromatography method. There was no significance between the N fertilization treatments and concentrations of alkaloids. On the other hand, tobacco leaves sprayed with ascorbic acid solutions before cure, had lower alkaloid contents, thus possibly preventing nitrosamine formation.
