CORESTA Congress, Kyoto, 2004, APOST 24
Effects of agricultural practices on tar potential of Burley tobacco
Istituto Sperimentale per il Tabacco, Scafati, Italy
In the frame of Tobacco Research and Information Projects, financed by European Community, a multilocation, five years study starting in 1997 was carried out on the production of Burley tobacco with low content of nitrogen, nitrate, alkaloids and low tar potential, (Project TAB.RES.INFO. T/19-24).The study was comprised three experiments: a varietal comparison, a variety x cultural techniques comparison, a nitrogen rates trial. As regards the Istituto Sperimentale per il Tabacco partnership and the effects on tar potential, the varietal and variety x cultural techniques comparison experiments confirmed one of the starting hypotheses, namely the possibility of tar potential reduction of Burley tobacco, using a well-suited variety choice and an increased number of leaf per hectare. Intrinsic variability of tar measures pointed out the need of further evidences, as well as the necessity of calibrating the choice according to the local pedoclimatic conditions. The maximum reduction obtained reached a little percentage of tar quantity per cigarette. In the nitrogen rates experiment, results were not conclusive; in soils with low levels of nutrients, lower nitrogen rates gave some tar reduction. Nevertheless, taking into account all the effects of nitrogen rates on tobacco, a reduction of fertilisation rates, involving a corresponding reduction of nitrogen compounds in cured leaf, mainly nitrate, seems to produce a less harmful tar, with no significant decrease of yield and quality of tobacco. An interesting result was the sensible tar reduction of Burley, untopped and harvested by leaf, according to the standard agricultural techniques of southern Italy.