Some Newly Discovered Plant Principlea.
In Agriculture we work with plants. We place them in the
ground and see them de-velope from the seed to maturity. We cultivate
them and feed them fertilizers. The product may be good or it may
be bad. The plant j s either worked well or it has not; but we can
not tell exactly why it has or has not worked well. The reason lies
in the fact that we know very little about the plnnt actually works.
In the living: plant we .e]. with A. mechanism which we c an
not examine in its most vital-parts; because, the moiient we in any way
interfere with the living' Protople.-pm, we kill it; and the dead propoA-
lasm is a wholly different subst;'.nce from the living Protoplasm.
Altho we cannot jnalyize the living Yxaiarotoplasm, we
can study the products of its action, ,nd its action upon the non-
living matter which is pre-sented it as food. In the process of fermen-
tation we have an exmp3.e of both the product of its action, and its
action upon non-living matter. Fermentations are familiar to every
one, .The cane syrup ferments if not pro: early taken c.re of; the
yeast ferments, making possible the lr:-e plump loaves of bread; the
milk ferments, which is rnot'1er -way of .aying that it so;rs.
In all these cases the fermentation is brought about by
the action of living protoplasm. Contaminations such as yeasts, bac-
teria and moulds, which are all living plants, h--ve fallen from the
air into the syrup. There they have -romn and multiplied, for they
have found a favorable place tp live. The syrup furnishes them a
super- abundance of food. Their living protoplasm breaks down the syrup
into alcohol and carbon dioxide, which is a gas commonly known as
carbonic acid ,as. The gas collects and rises in the syrup giving it
its frothy ap-p.--rance; and the alcohol present gives it its character-
In the milk, nryrisds of n nall ncteria hu..ve found a favor-
able place in w, ich to live. They are growing and multiplying, break-
ing down the milk .ugar into Lactic acid which gives the milk its
In each of these cases we iu.ppose that the protoplasm was
in dire-ct contract wivtl the oyruip anrd with the niilk, snd provoked the
decomposition of each.
In the case of the yeast, which is a small one celled plant,
we have a deco-",p ,sition of fu~ ar into the alcohol and carbon dioxide.
But the decomposition is not brought about, by the direct contact of
the protoplasm with the su ar. Instead the protoplasm has secreted
a substance which we will calma. plant Principle, and which is known
in scientific literature as an enzyme, that stimulates the sugar to
break down thto alcohol and carbon dioxide.
Altho we have known for .;everr.l centuries that the yeast
plant can provoke the braeking down of su ,ar, it has only recently
been discovered that the yea,;t does so by its protoplasm secreting a
plant principle or ehzyrne that does tVe work. This substance has
been named Zymase.
These plant pinri.ciples are very abundant in the vegetable
kingdom. Thebacteria in the soil secrete them, thus locking u p the
nitrit-n from the air into ammonia and related. compounds. One mould
fungus is known to secrete ten different ones. 'Ihey may be equally
abundant in some of the higher plant~. Seedn germi.rate by their con-
verting the stored food into a form usable by the yorng plant until
it can become established in the -.oil. The fertilizers take n fcrom the
soil are modified greatly by the enz ,ies in the plant before they are
in a condition to be used by the protoplasm. The enz~ynmes chln;nge the
plant food into an insoluble form that it -:ay be stored; and later
changes it back into the soluable form that it may be carried to all
parts of the plant for use. They are very active during the growth
and ripening of the fruit.
I 1 They aid in the carrying on of all the life processes, such
as digestion, respiration and growth. During respiration, the union
of the oxygen with the tissue is accomplished by their help. Digestion
is almost wholly an enzyme action.
On the other hand, instead of being friends, they maybe an
aid to the enemy of the plant; or they may even be the enemy itself.
The fungus bores its way into the plant by means of the enzymes it
secretes. The Mosiace Dise of the To) noco is tho 'ght to be due to an