Evening star., 1935-08-01
STARS, MEN AND ATOMS
Notebook of Science Progress in Field,
Laboratory and Study.
BY THOMAS r. HENRY.

An obscure substance known as panto-
thenic acid may be universal growth
elixir
Preliminary experiments in which the
weight of alfalfa plants was nearly
doubled by placing minute quantities OF
this acid in the nutrient solution in
which they were grown are reported in
the proceedings of the National Academy
of Sciences by Charles H. McBurney
Walter B. Bollen and Roger j. Williams
of the staff of Oregon State College.
This acid, they explain, apparently is
a constituent of nearly all living tissue
plant or animal Not only is it a growth
stimulant, but it plays part in the
fixation of nitrogen in the soil where it
becomes available for plant life. To
learn the mechanism of this process was
the primary purpose of the experiment.
Nitrogen is taken from the air and
fixed in the earth through the co-opera
ton of the leguminous plants, such as
alfalfa and clover, and certain soil bac-
terra. The latter form nOduleS on the
roots of the plants and at some stage in
this process the nitrogen fiXation occurs.
Just what happens, nobody has been able
to determine. So far as known, the bac-
JeIld Will IlOG 1lA CllC lllOlOSCII III GLlC
absence of the plants, nor vice versa.
Fixation has not been demonstrated ex-
cept where the plant bacteria relation
ship exists. The presence of the bacteria
is necessary for the healthy growth of
the plant.
The Oregon scientists found first that
the bacteria produce this pantothenic
acid. The amount produced increases
ctoodi1u tho ha q
fact demonstrated by raising these mi
mute organisms in sugar solutions. Thus
as the bacteria feed on the roots of the
alfalfa they pass on to the plant the
excess amounts of this acid which they
are producing, thus in turn stimulating
it's growth so that the partnership can
be continued, and in the process fixing
nitrogen in the soil so that other plants
which are parasitized by the organisms
can live and grow upon it.
In the experiment reported alfalfa was
grown in solution in three sets of test
tubes. One set contained only the ordi-
nary plant nutrients. One was innocu-
lated in addition with soil bacteria The
third received the minute amounts of
pantothenic acid After a few days it
oCSoAlC dPPoICIlG GIldG LIE pldI1CS IN Ine
third set were uniformly larger and
healthier than those in the other two.
The difference between them and those
grown in the nutrient solution alone was
striking. Those grown in the solution
containing the bacteria were almost,
but not quite, as vigorous.
Growth continued for a month, after
which all three sets of plants were har-
fn@ 1lA -, -
a growth Of 81 millimeters, as against
As millimeters for those grown in the
tubes containing the bacteria and 81
millimeters for those which had been
treated with the pantothenic acid. The
total weight per plant of the first set
was 4.70 milligrams, of the second ITO
and of those which had had the benefit
of the pantothenic acid, sos. Since the
chemical composition of all the solution
had been rigidly controlled, the pres
ence of the bacteria and of the acid
afforded the only possible explanation
for the increased growths.
Wien it came to nitrogen f1xation In
the solutions, however, the score was
very heavily in favor of the bacteria. In
the test tubes to which the pantothenic
acid had been added there was only
trifle more than in those where the
alfalfa had been grown with only a
nutrient solution. AS matter of fact,
the acid contains no nitrogen itself. Its
actual formula still has to be worked out
satisfactorily by organic chemists.
n *x
At the fixed nitrogen laboratory Of the
Department of Agriculture two years ago
there was demonstrated the nutritional
need of the soil bacteria for some un-
known substance which was DESIGNATED