The Colfax chronicle. [volume] (Colfax, Grant Parish, La.) 1877-1981, 1907-08-31
SOUTHERN
AGRICULTURE
wiz disease Of Cotton.

The wilt of cotton, olten cdieu
"black-root,' is in many ways one Oh
the most troublesome cotton diseases
now known. 1t is not so well known
throughout the state that a very BRIEF
description of the most important sys-
TENS of the trouble will here sunice.
II makes it's first appearance at about
this time of the year, and II appearing
for the lrst time in any given neio
will be confined to small area. from
this area. however, 1t viii be distribut-
ed year after year through the agency
of plows and mules passing over the
ground. The plants attacked soon ap-
near TO be dwarfed and somewhat un-
healthy: the leaves turn yellowish at
the margins and this yellowisn color
proceeds slowly towards the center
of the leaf. The vines In such cases
may long remain green and healthy.
some plants may wilt and die In a
very short time, but others may send
ont new shoots down close to the
ground and outgrow the attack. The
/ f,nal test is to be found in an examina-
ton of a cross section OF the stem OF
root II affected with the wilt the
woody part will appear to be stained
q brownish color.
/, The wilt is due to the attack OF tne
fungus called Neocosmospora vasin
fecta. This fungus lives in the soil
and apparently can retain Its vitality
IN the soil for Ave years, or even
longer It first enters the plant
through its smaller roots, and 1t Is
supposed that the nematode worm IS
an important agent In wounding the
roots which they enter, thus permit
ting the ready entrance Of the VIII
fungus into the root. It Is at least csr-
tain that sandy soils infected with TINS
uematode worm that causes the root.
knot disease of cowpeas. cotton ans
= host of other plans, are more apt to
become infected with this wilt fungus
A great many farmers have In fac'
learned for themselves this connection
between the nematode worm and the
Wit. But 1t is also to be borne II
mind that the wilt fungus can ente'
the cotton roots without any assistance
.. III is in fact an aggressive parasite
: Having gained entrance into the cot
ton root It then grows in the wood!
vessels. or ducts, of the root and stem
and finally, by plugging up these nat
. ural water channels OF the plant
causes the whiting symptoms abov
mentioned.
. The above facts suggest certai
( measures that every farmer can reat
!. ily apply to his fields with advantas
Il in the control Of this dangerous cotto
Ir enemy.
It Crop Rotation--It must be remen
70 bered that this fungus. causes WI
IT disease in olxra also and hence tn
n ulant should not be grown in rotate
- with cotton. In fact soil once infecte
" should not be planted for several yea
TO cotton, okra or any other crop tn
N Is subject to the wilt disease.
~ Destruction of Filt-Infected Plants
IN Cotton stalks affected with the W
H. should be pulled up and burned
- once. HIS RlOCC0oAO "@aA 80
- duce the spore production OF the ~
"a gus and thus reduce Its spre
~ throughout your fields.
Ia Quarantine Infected Areas-The
a., binary grazing Of cattle over infect
~ fields. will tend to carry the discs
he from infected to non-infected are
ba This is done by the adherence OF
en- spores and vegetative portions OF
ed fungus to the feet Of the cattle.
~ fact, an infected area should be
md once placed under regular cuarant
un- regulations. For il you plow acr
be an infected area into the balance
ire your field you will certainly ca
some of the fungus along on the pl
we. and thus spread the disease.
vas ordinary means the fungus has
the spreading is by its growth in the
en- and hence somewhat larger
should be guaranteed than that
II - - Ill nu&~1