The Bamberg herald. [volume] (Bamberg, S.C.) 1891-1972, 1910-10-06
Corn Ear Rot.

during the past t"O years Ilele
seems to have been a gradual in
crease in the amount of damage or
rotten corn in the fields througout
the State. Investigations started last
fall and continued this summer show
that the large majority of this trouble
is due to a fungus disease known as
dry rot or ear rot of corn. In one
field recently investigated in Darling
ton county we found 20 per cent. of
the ears DESTROYED by this disease.
Reports have come in from other
sections showing that the disease is
widespread and is causing consider
able damage. Now any disease that
Injuries our corn crop is of vital in
terest, and every farmer should know
enough about such a disease to en-
able him to recognize it when he
comes in contact with it, and to en-
able him to combat it where it causes
loss. 1t is hoped that at least a part
Of such knowledge will be gained
from this article.
Symptoms Of the disease are very
characteristic. At the time the corn
begins to ripen, the husks of the dis
eased ears turn prematurely yellow.
Later. they assume mottled or
blackish appearance and seem to
stick very close to the ears. When
the husks are pulled back from such
ears, the grains will be found to be
shriveled and immature and the ear
will be noticeably decreased IN
weight. Later, the grains appear
very brittle and frequently assume a
brownish color. At this stage the
whole ear is usually overrun with a
white looking mold. When the dis
eased ears are broken across, small
black fruiting bodies of the fungus
will be found on the tips of the grains
and in the cob.
This rot is caused by parasitic
fungus, diplodea maydis. Studies of
the life history of the fungus recent
ly made at the Nebraska and Illinois
experiment stations show that the
fungus lives over winter on the dis
eased ears and stalks which are left
in the field. It spreads from these
to the new corn the following season
at the time the corn is in silk and
tassel. The infection takes place
through the silks. If the weather
conditions are favorable for the de-
velopment of the fungus at this stage
the disease spreads very rapidly. At
the Illinois station the fungus has
been found to live on the old corn
stalks in the field for two years, and
in some cases for three years. They
recommend that the corn stalks be
removed from the field and be de-
stroyed and that rotation be prac-
ticed which will keep corn off the
land for two years. 1t seems that
such measures would eliminate the
disease. I have in mind one case in
this State, however, where the dis
ease has done considerable damage
in the face of such rotation, so it
seems that some further data are
needed before we can give definite
measures for controlling the disease.
In this connection it is we'll to keep
in mind the fact that removing the
corn stalks from the field eliminates
one of the principal sources of infec-
ton for the next season. This en-
phasizes the advantage to be gained
by cutting and shredding the corn.
AS stated above, however, we need
more data which will apply to South
ern methods and conditions. In Or
der to secure such information, we
need cooperation. We are pushing
this investigation now and are asking
that every one who has the disease
in his field will write us about it and
send us specimens. We have on hand
a number of franked tags which will
bring specimens through the mail
free of cost, and we will be glad to
send these to anyone desiring to
send such specimens. Where cases
seem to warrant it, we will be glad
to visit fields where the disease is
causing trouble and look into the
conditions prevailing there.-H. w.
BARRE, Botanist, S. G. Experiment
Station.