Lawrence democrat. (Lawrenceburg, Tenn.) 1884-1925, 1904-09-09
AND PLANTER.
COTTON ANTHRACNoSE.
A Disease which Georgia Cotton
Planters Have Been Called to
Battle With of Late.

STATE entOmOlOglSt, snow mat the loss
Is being caused by the disease of cot
ton known as anthracnose.
The appearance of this disease is
most characteristic and most common
ly noticed as 1t occurs upon the bolls,
although it does occur to some extent
upon both the leaves and stems of the
cotton plant.
The first symptom of the disease
upon the bolls is the appearance of
small red specks or dots, These rap
idly enlarge in size, with the result
that the part of the surface affected
becomes sunken and soon attains a
blackened color. These diseased areas
are usually circular or oval in form,
but as several spots frequently occur
areas soon or later unite so that
half or even more of the boil Is af-
fected. Spores are developed upon the
blackened area, and although they are
colorless, their abundance gives the
centers of the diseased areas a grayish
appearance. These spores correspond
to and have the same function as do
seeds of higher plants, and 1t is by
means Of these spores that the disease
is spread from boil to boil and from
plant to plant The attack of the an
thracnose fungus oftentimes results
in the boil remaining closed, and the
ind NIT Iva, foi n tiny
times the tip of the diseased boil will
open up slightly, but in this case 1T
also fails to mature, and the boil
eventually dries up, assuming a dark
brown color. Strangely enough, the
attacks from this disease are often at
tributed to insects, the cotton planter
believing that the hollis have been
"stung" by some very small and elu-
sive insect, and that he sees only
the effect of the poisoning" AS a
matter of fact, insects are in no way
I responsible for this trouble, and have
no connection with it whatever, aside
from the possibility that certain in
sects may carry the spores upon feet
or beaks as they travel from one plant
to another.
This is a case in which the remedy
is hard to apply, partly because of the
nature of the disease, and also be-
cause the mofphology and life history
of the fungus causing the disease have
not been thoroughly worked out by
scientists. An intimate knowledge OF
all stages of a disease or Of the de-
velopment Of an insect, in most cases,
gives clew to how the disease or in
sect may be successfully dealt with.
This very necessary intimate knowl-
edge of insects and diseases can only
be obtained by careful and thorough
scientific work, hence it is that the
scientific work proper is indirectly of
the greatest Importance to the farmer.
At this season of the year July,
August and September), we know Of
nothing the farmer can do to check
the cotton anthrcnose, except that
possibly where the disease has not OBJ
tanned much Of start, the diseased
bolls could be carefully picked off and
burned up, thereby reducing the crop
of spores that will later spread de-
struction through the field. Even in
this case the fungus is likely to have
obtained start upon the leaf-scars
and injured parts of the stems, and it
probably could not be entirely eradi-
Gated in this manner. In fact, the
practicability of this plan is question
able, but it is the only plan that can
be applied at this season that offers
any chance whatever of success.
Spraying the cotton plants with some
fungicide, like Bordeaux mixture, Is
impracticable, as the fungus obtains a
nold deep in the tissues OF the cotton
plant, where it can not be reached by
any applications.
In spite of all this, the planter can
take some very sensible measures to-
wards reducing the damage from this
disease another season. 1t seems
highly probable that the fungus of
this disease may continue to live in
the soil for some time and thus rein
feet the following crop of cotton. In
localities where the anthracnose oc-
ours therefore, cotton should not be
planted next year upon land that has
cotton upon it this year. In other
words, cotton should not be placed
upon the same field two years in sue
cession. This is only a part of the
doctrine of rotation of crops" Did
the farmer carry out systematic and
intelligent rotation of crops, year after
year, in which the same crop never
succeeds itself upon the same piece of
land. his losses from insects and dis
ease would be greatly reduced without
any attending cost whatever, and in
addition, the fertility of his soil would
be conserved to greater advantage.
The selection of cottonseed for plant
ing in locality where anthracnose &C.
ours, Is of the greatest importance.
Two courses are open in the use of
seed. One is for the planter to secure
for next years planting, cottonseed
from locality where the anthracnose
does not occur, as it has been clearly
demonstrated that the spores of this
disease are frequently retained in the
lint upon the seed, and are hence ready
to infect the young plant as soon as it
splits the seedcoat
The other course would be for the
afflicted planter to carefully select re-
sistant seed from the diseased areas
upon his own plantation. In almost
every badly diseased field, plant will
be found here and there which shows
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