Atlanta semi-weekly journal. (Atlanta, Ga.) 1898-1920, 1918-09-17

disease by reason of the characteristic
appearance a cross section of the stem
presents. This disease may kill the
plants in May. or along any time during
the summer until mid-September, When
the plants are practically mature.
When the disease first appears IT US
uaIly develops in a small, rounded or
irregular area which enlarges as the
season advances. Outside the spots
where the plants are killed or dwarfed,
many plants may partly or completely
survive and produce half or even
normal crop Of cotton.
Cotton wilt is the result of fungus
Under the microscope il appears as a
small moldlike plant growth, which en-
ters the root from the soil. As soon
as il gets into the plant it grows Wig
orously throughout the water-carrying
vessels of the roots and stems. This
causes them to turn black. AS result
of it's development the supply Of water
is in part or wholly cut off and the
death of the plant soon follows. This
fungus reproduces in great numbers
several types of fruiting bodies, ~
which it is propagated. 1t is cloSeE
associated TO the fungi which cause the
wilt of okra, cowpeas, tomatoes, water
melons and potatoes. 1t has not how
ever, proved to be communicable to
other plants.
Naturally the disease is easily and
rapidly spread when il once establishes
itself For instance, the fungus may
be carried from one field to another on
cultivators, plows and other tools. The
feet of men and animals may transfer
it Wind may be a potent cause OF its
wide distribution. Drainage water and
erosive rains may carry il from one
NEa 20 m
manures and compose heaps infested
with the fungus may also result In It's
being widely spread over increasing
areas of land from year TO year All OF
these methods of distribution shoud'
therefore be studied and controlled in so
far as il is practicable to do this. AT
least much may be done to lessen It's
spread because now no effort to speak
Of is made in this direction by the aV-
erage farm on which the disease mas
made it's appearance. For some reason
,bis trouble is also more serious on
sandy or sandy loan soils and naturally
1-et seasons seem to favor its develop
ment. These are conditions, of course
over which little control can be exer-
cised in a general way, but speclnc
methods of fighting the disease as
poiuted out later, will enable its being
handled successfully even under condl-
lions similar to those portrayed. Late
cotton. of course, is as badly atIackeo
by wilt as that which is planted carry.
II has also been proven that tunglcloes
and fertilizers do not control II. me
use of kainit. acid phosphate, salt, 1me'
Dotasb nitrate of soda and other forms
of soil amendments and fertilizers has
failed to give any material RELIEF. sou
fupgicides are of course, too expensive
IN be worthy of consideration.
In lighting this fungus the rotation
~ crons is an important matter. This
disease can live on decaying organic
matter in the soil for good long Tune,
hence il is weIl-nigh Impossible 10
starve IL out, so a short rotation Is Oh
little benefit. In fighting the disease
on land which is badly infested rota-
zion Of from seven to ten years should
he instituted. In other words. cotton
should not he grown on land Oh THIS
character oftener than once In seven 10
zen wears After great effort ana laoor
ON the part of investigators ana the IOl-
lovvinp nm of many false trails II was
6paIly shown that the best method OF
fghting this disease was through Ihe
nIanting of what are known as VIII re-
sistant varieties. II occurred 10 soiile
of our scientific Investigators VINO are
Studying this disease that in every nelo
ottacl-ed there appeared to be plants
which were not injured. AT hrst IL was
difFicult to understand just how or why
mis- should be. Later it occurred 10
these men that these plants possessed
some characteristics which made them
more or less immune to the fungus. 1t
was found that by selecting plants from
sreas where all the others had dled ana
nIanting them on diseased land that
large percentage of them proved re-
sistant and so il came about thAt
through continuous selection OF the SEED
of such strains that varieties OF cotton
have finally been evolved which can
he nIanted with large measure OF sue
cess on badly infested land and still
very good crop of cotton be harvested
therefrom.
Among the first wilt resistant strain
NJ cotton developed was the Dillon. This
VAS a limbless cluster variety derived
from the old Jackson Limbless. 1t was
a strain quite well adapted for cultiva-
ton on certain types of land, but the
fact that il was a cluster cotton and
rather hard to pick did not commend it
to the favorable consideration of many
10