The Marietta journal. [volume] (Marietta, Ga.) 1866-1909, 1904-10-13
COTTON ANTHRAcNosE.

81 serious trouble IN their cotton fields.
Specimens of the injured plants and
bolls which have been sent to the
Georgia Department OF Agriculture and
and to the State Entomologist. show
that the loss is being caused by the
disease of cotton known as "anthrac.
nose"
The appearance of this disease Is
most characteristic and is most com.
monty noticed as 1t affects the bolls,
although 1t does occur to some ex.
tent upon both the leaves and stems
of the cotton plant.
The first symptom of the disease up.
on the bolls is the appearancaof small
red specks or dots Thesy rapidly
enlarge in ize with the result that the
part of the surface affected becomes
sunken and soon attains a blacHened
color. These diseased areas are
usually circular or oval in form, but
as several spots frequently occur upon
single boil, these areas, sooner or
later, unite so tina thelf, or even more,
of the boil is affected Spores" are
soon developed upon the blackened
area. 1t may be we'll TO explain here
that these fungus" diseases as they
are termed, are caused by very low
forms of plant life-in reality vege.
table organisms of a very simple
form. Like the higher type of flower.
ing plants with which we are all ia,
miliar there must be provided some
means by which the plant is pvopa
gated and spread Towering plants
produce seeds, and while it cannot be
truthfully said that the "fungous"
plants produce seeds, yet they do
produce spores which correspond In
their function to the seeds of the com.
mon plants. These spores are distrib.
ted by winds, insects, and in other
ways and terminate very much as do
seeds of grain or other plants, and
again start the disease in new
locality or upon another plant. As
stated above, the spores of the an.
I'LL aShOoCf IN upOu luc DldCkp0Gu
areas Of the diseased bolls, are color.
less, but they become so abundant
upon these diseased areas that they
give the latter grayish appearance.
It is by means OF these spores that
the disease is spread from boil to boil
and from plant to plant in the cotton
fields.
The attack of the anthracnose fun
gus oftentimes results in the bolPs re.
naming closed, and the lint within
fails to mature. At other times the
tip Of the diseased boil will open up
slightly; but in this case also the lint
fails to mature and the boil eventual.
ly dries up, assuming dark brown
color.
Strangely enough, the attacks of this
disease are often attributed to insects,
tn ecotton planter believing that the
bolls have been "stung" by some very
small and elusive insect and that h,
sees only the effect OF their poison.
ing" AS a matter OF fact, insects
are in no way responsible for this
trouble, and have no connection with
it whatever aside from the possibility
that certain insects may carry the
spores of the disease upon their feet
or beaks as they travel from one plant
to another
This is case in which the remedy
is hard to apply, partly because OF the
nature Of the disease and also because
the morphology and life-history of the
fungus causing the disease. have not
been thoroughly worked out by scien.
lists. An intimate knowledge Of all
stages OF a disease or of. the develop.
ment Of an insect in most cases gives
clew to how the disease or insect
may be successfully dealt with. This
very necessary intimate knowledge OF
insects and diseases can only be OBJ
tanned by careful and thorough scien
tific study, by using the highest power
microscopes and by observing the in.
sect or disease in all stages of its de.
velopment and existence, and noting
its Behavior upon different plants and
under differing climatic or weather
conditions. Hence it is that the sci
entific work proper along these lines
is indirectly Of the greatest impor
lance to the farmer.
At this season OF the year July, An.
gust and September) we know OF
nothing the farmer can do to check
the cotton anthracnose, except that
possibly where the disease has not OBJ
tanned much OF start, the diseased
bolls could be carefully picked of
and burned up, thereby reducing the
crop of spores that will later spread
the destructive disease throughout
the entire field or plantation. Even
II this is practiced, however, the an.
thracnose fungus is likely to have OBJ
tanned start upon the leaf-scars and
injured parts Of the stems and it prob
ably could not be entirely eradicat ter
by this Manipulating method. In fact
the practicability Of this plan is ques
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