~ MISCELLANEOUS PAPERS. 
B. P. I.—388. 
THE RELATION OF NICOTINE TO THE 
QUALITY OF TOBACCO. 
~ 
By WicutTman W. Garner, Scientific Assistant, Tobacco Investigations. 
VARIATION IN THE NICOTINE CONTENT OF TOBACCO. 
Nicotine has long been recognized as the characteristic alkaloid of 
tobacco, but its function in the economy of the plant is not under- 
stood. It is present in the plant in the earliest stages of growth and 
is found alike in the roots, stalks, stems, and leaves. As the develop- 
ment and growth of the plant proceed the percentage of nicotine con- 
tained in the leaf constantly increases, reaching its maximum at 
maturity. On the other hand, as is well known, the maximum con- 
tent of protein nitrogen is found in the young green leaves which are 
growing rapidly. These facts seem to indicate that nicotine does not 
enter into the synthesis of the albuminoids from simpler forms of 
nitrogen, but rather that it is derived from katabolic changes in the 
albuminoid constituents, and thus continues to accumulate in the 
tissues so long as these are vitally active. 
The amount of nicotine contained in tobacco from different sources 
is subject to very wide variations, some samples containing less than 
1 per cent, while others contain more than 5 per cent. The produc- 
tion of this alkaloid in the plant is influenced by a large number of 
factors, the relative importance of which has not been determined. 
No reliable conclusions can be drawn from a study of the nicotine con- 
tent of tobaccos grown in different parts of the world for the reason 
that we are always dealing with a complex group of factors and the 
effect of any single factor can be determined only by experiments so 
planned and conducted as to exclude, or at least to control, the effects 
of all others. In a very general way, however, it can be said that 
very rich heavy soils and excessive quantities of nitrogenous fertil- 
izers, which tend to produce a coarse, rank growth, produce a high 
percentage of nicotine. This relation is but a rough one and ap- 
plicable only to sharply contrasted differences in soils and fertilizers. 
The investigation of this subject carried on by the writer, though as 
yet incomplete, points unmistakably to the fact that in the case of any 
given variety of tobacco grown in a particular locality—that is, under 
approximately the same environment—the percentage of nicotine in 
different strains is roughly proportional to the albuminoid nitrogen ; 
but when markedly different varieties grown in different localities 
are compared, this relation does not hold. 
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