Nov. io, 1913 
Alkaloidal Content of Belladonna Plants 
143 
green plant per acre. Carr 1 claims to have found a certain relationship 
between the amount of sunshine during the growth of the plant and the 
percentage of alkaloids found in the stems and leaves, claiming that 
plenty of sunshine and limited rainfall have a tendency to stimulate the 
production of alkaloids. 
Although soil and climate may have considerable influence on the 
alkaloidal content of plants, yet to establish this as a fact beyond all 
doubt is a difficult matter because of the individual variation involved. 
Until experiments have been conducted upon a large number of plants 
which show a minimum variation in their alkaloidal content, nothing 
definite can be said upon this point. In working with a limited number 
of plants collectively, an abnormally low or high percentage of alkaloids 
in the leaves of a few might so affect the yield as to make the average 
entirely misleading. Likewise, this individual variation becomes an 
important matter in the sampling of large quantities of leaves and roots. 
In order to secure a reliable sample, it should be of considerable size and 
selected only after the leaves or roots have been thoroughly mixed. 
INDIVIDUAL VARIATION THROUGH SEVERAL SEASONS 
Having definitely established the fact that great variations exist in 
the alkaloidal content of the leaves of individual plants, the question 
remains to be answered whether such variations exist only during one 
growing season or whether they manifest themselves in the same propor¬ 
tion in following seasons. If plants which are rich in alkaloids one season 
are correspondingly poor the following season, then it is logical to assume 
that the production of alkaloids in the plant is dependent on factors 
which change from year to year. If it Were definitely known what r 61 e 
the alkaloids play in the metabolism of the plant, it might be easier to 
determine what factors influence their development. As has been 
shown, the physical appearance, or, in other words, the vitality and 
growing power of the plant, appears to bear no definite relation to the 
development of alkaloids. Furthermore, if soil and climate are the 
potent factors, then their influence ought to be felt by all plants alike 
when all are grown on similar soil and in the same locality. Such, 
however, has been found not to be the case, and reference to the tables 
shows that there were plants rich and poor in alkaloids in every year 
during which the observations extended. On the other hand, if it 
should be found that a plant with leaves containing an unusually high 
or low percentage of alkaloids in one season shows the same characteristics 
in following years, it would be safe to assume that there is a definite tend¬ 
ency in that plant to produce a small or a large quantity of alkaloids in the 
1 Carr, F. H. The effect of cultivation upon the alkaloidal content of Atropa belladonna. Chemist 
and Druggist, v. 8i, no. 1703, p. 43-44, 19x2. 
