The Manning times. [volume] (Manning, Clarendon County, S.C.) 1884-current, 1901-01-30
PREVENTIVE MEASURES.

PREVENTIVE MEASURES.
In the cotton wilt, as in many other
plant diseases, certain preVen,iVe OF
palliative measures, based on our
kDowledge Of the say the disease
SPREADS, are very important, These are
q, follows:
l. Rotation OF Crops -Lsnd once in
fected with this disease has never been
freed from it. 1t is important, there
fore, that such land should not be
plsutsd for several years TO okra or any
variety Of cotton subject to this dis
ease. The length Of time the fuogus
will live 10 the soil is not yet deter
mined, but four years rest has proved
sufficient in several cases. Other
crops, SIS corn, coEpeas, ca aobage, water
melo1, etc may, it is believed, be
planted on this land With safety.
The greatest spread Of the wilt dis
case is by the direct growth Of the fuo-
gus through the soil from diseased to
healthy areas. Ga this account an area
considerably larger than thas on which
the plants sre wilted sh ,uld be included
in this rotation.
2 Removal Of Diseased ts-An
other important sources Of infection is
the diseased plants themselves. The
fungus produces on the dead stems and
roofs great numbers OF spores, which
are carried to othe, places in variety
of ways. All diseased plants should be
pulled and burned as soon as discover
ed, 50 as to prevent the dispersion Of
the fungus spores which will finally
cover them.
8 Avoidance Of Spread by Cattle,
Tools, Eeo.-The writer's observations
in various places in South Carolina dur
ing the past two years lead him to be
lieve that cattle grazing in the fields
spread the disease. They should not
be allowed TO pass freely from Infected
areas TO healthy fields, and would be
better not to pasture such infected
islds. Tools should be carefully
cleaned after culsivsting the disease d
land. To insure complete destruction
Of the spores of the wilt fungus, So,
tools shonld be secured clean and then
washed with 2 per cent solution Of
formslin or per cent csrbolic sold
solution.
4. Gaze Of the Compost Hesp.-The
fungus is sometimes introduced into the
bsrnyard aud compost heap, 80 that the
manure becomes g source of general
Infection to healthy fields. The utmost
care should be taken to keep diseased
plants out of the msnure, and if there
arc any Indications that such plants
have found their Rsy into the manure,
all such manure and compost should be
used on land where cotton will never
be planted.
There is no objection to the use ol
stable manure which does not contain
the spores Of the cotton wilt fungus.
but experience has shown that in the
case of the closely allied watermelon
wilt fungus barnyard once infected
will remain 50 for many years, aud tbs
all manure taken out Of it will be like
IL to spread the disease. Tne same il
probably true Of the cotton wilt fun
gus.
The most encouraging results have
come from the endeayer Of the depart
nens to Sad race OF cotton which ca1
Be grown on the infected lands. There
are always some plants in every helo
which resist the disease to CRATER o.
less extent, and it frequently happen:
that Of Two plants Ia the same hill
| eq1slly exposed to infection, one vii
die and the other live to the end OF tn
| season. All degrees Of resistance ma.
be found, from plants nearly killed b!
the wilt disease to those entirely
healthy. The latter a.e comparssiVel!
uncommon, however.
D.fereos races Of cotton vary consid
erabl, in their susceptibility to the vii
disease. This vas shown By an ezpeil
meut carried out by the department Of
the farm of Mr. q. L. Galloway, at Dbl
lon. s. G.
It will be seen that some Of the Des
kinds are among those most injured b.
this disease; but there were one o
more plants il ea,h race that entlrel!
wl,hslood the disease, and the seet
from these has been saved With the IN
tention of securing valuable resistan
st7ains By crcss breeding them.
The ability Of certain cotton plants t.
grow on infected land is due to the FAC
that the wilt fungus is uoable to ense
their principal roo. system and not t.
any lack of infection. This has eee'
determined BY microscopic examination
That infection Of these plants has real
ly taken place may be demonstrated b.
an examination OF their roots for tn
litsle satts of rootlsts which mark tn
location Of infections. The zoos o
plants taken from the TOW OF Jsnro
| visch cotton were attacked By the fun
gus in evsr 8 hundred PAGES, as foua'
| ~ H.S th