Atlanta semi-weekly journal. (Atlanta, Ga.) 1898-1920, 1919-05-30
Fighting Disease Organisms

1t has been our practice for long
time to ignore the Importance of
plant diseases. We prepare large
areas of land, sometimes fertilize it
very carefully and then plant 1t
with as much skill as we can sum-
ymon to our command. Somehow or
other we. feel that if we have done
this we have met the requirements
of the situation and that the Lord,
out OF the abundance of His heart,
will insure us a bountiful harvest.
We have somehow felt that the
study of plant diseases and the Or
ganisms which produce them was
not worth while, and so we have
ignored this subject until many dis
eases have really become a menace
to the success of our agriculture,
like the bad spirits and the evil sug-
gestions which take root in the HUI
man mind and finally overcome the
resistance of the conscience. These
diseases have multiplied and estab-
lished themselves so completely in
many locations that they threaten
the very existence of the farmers
crops. ...
1t is futile and a waste of human
energy, therefore. to plant crops
without considering the nature and
character of the diseases to which
they are subject and the best means
of fighting these disease organisms
so they may be held in allegiance,
controlled or eradicated altogether
as is frequently possible. No great
er service can be rendered our read
ers than to direct their attention
specifically to this important
problem and to advise them in a
general way relative to the more
common of the diseases which occur
in the southeaster states and the
best methods of fighting them.
The soil organisms producing dis
ease in plants consist of various
fusaria, sclerotium rolfsii, nema-
tode, etc, commonly known as wilt,
blight. damping off, root knot, etc.
Most soil organisms are able to live
plants be absent. Sooner or Later I
however, they are greatly reduced
IN number or else entirely eradicat-
ed. Crop rotation, therefore, becomes
the chief means of combating this
group of diseases. First must be
determined the length of life of the
disease organism in the soil when no
susceptible crops are planted and
this information determines the
length of rotation to adopt Second,
the rotation must be so arranged as
to include disease-resistant crops
which will flt in with the scheme of
farm management. The susceptible
crop, or crops, should not appear
more than once in the rotation. For
tour or hVe years will prove success
full.
The second class of diseases are
largely of bacterial origin and quite
dincult of control. Usually the
elimination of insect damage will re-
duce the disease damage to mini
mum. Often it may be advisable to
collect diseased plants. or prune out
diseased parts for destruction (burn-
ing). 1t should be borne in mind
however, that the hands and cutting
tools may carry the disease. This
may be prevented by use of a dis
infectant material.
Occasionally it is found that one
or more strains of a certain suscepti-
BILE crop are resistant to particu-
lar disease, or that it is possible to
develop a resistant strain through
selection and breeding. In the con-
troll of fusarium wilt of both cotton
and tomato the development Of wilt
reGis Sant strains has proved practi-
cable. Very often the grower can
through field selection of seed from
he tiny plants. Such q practice car
ried OFT consistently over a period
of +" should result in a high de-
gr re- resistance. to disease.
1t is certain, indeed, that the
aG- g.. OF q systematic crop rota-
tic7 cc1bired with proper selection
Of sccd will result in the reduction
OF crop losses from disease of this
gre - to minimum.
~ diseases are easily spread in
or. larry farm PRACTICES; use of dis
ea ed seed, slips, plants from bed ;
SCI: attached to farm implements,
tools, the feet OF stock and men,
etc.; the run off" from a disea sed
to q healthy field: wind blown litter
from diseased fields; and the use Of
manure resulting from diseased
feed. Proper precautions must be
taken to, avoid spreading of the dis
ease. Confine it to the particular
field or fields until eradicated
The diseases. of the aerial portions
of the plant may be subdivided into
two classes: (1) those which are
disseminated by wind, rain, ETC., and
CD those which are spread by in
sects. particularly sucking" insects.
or which find an opening for attack
In the wound made by the insect.
The first class are usually controll-