Saint Mary's beacon. [volume] (Leonard Town, Md.) 1867-1983, 1914-01-15
New pisesss Of Sweet Potato
Discoveries in virsinia.

WASHINGTON, ID. CA new disease
he foot rot OF the sweet potatoe, has
recently been discovered by the path
ologists Of the L. :. Department al
Agriculture, which threatens 10 ma
terially restrict the production Of the
crop in certain localities Ii was first
observed on sweet potatoes growing
in the vicinity of the Dismal Swamp.
Virginia. during the summer of 1912.
At that time ii was believed to- he very
limited in its distribution since search
for IL elsewhere was unsuccessful.
The next summer, however, il was
found in other parts of Virginia.
namely, at Cape Charles and Keller.
II is probable that it occurs elsewhere.
At all these places considerable dam
age was done to the crop, and in some
fields as much as 60 tn % percent. of
the plants were diseased.
The disease i known "a foot rot
and attacks primarily the lower part
of the stem from the soil line tn four
or five inches above il. The fungus
kills the plants by the destruction of
the cpidermis Or bark of the stem.
Sometimes the organism may attack
the vine several feet FRI m the hill.
usually where the leaf is attached and
from there spreads in both directions.
Small black bodies about the size OF a
pin point and just visible TO the naked
eye are formed on the diseased spots.
These are the fruiting bodies of the
fungus. From the destruction occa-
stoned by this disease during the sea
sons of 1912 and 1913. il is not unlikely
that il may be n serious menace to the
crops in localities where il occurs.
To what extent il may spread cannot
be forSeen, though it is likely To be
confined to somewhat humid regions.
The disease may be distributed in
several ways. 1t has been found in
the hot beds on the slips and is pro-
badly carried on them TO the field. 1t
has been shown also that the organism
will grow from the affected potato onto
the slips growing therefrom. Further
more. the fungus will grow from dis
eased plants onto the potatoes pro-
duced from them. The organism
causing the disease lives over the
winter on the dead vines in the field
and may infect healthy plants when
set out in the spring.
The sale and exchange of potatoes
or slips is another method of dis
tributing the disease from one farm
to- another, or from one locality 10
others % similar kind, may be dis
tributcd on farm implements, on the
feet of cattle or horses which roam
from one field to another. The spores
may even he carried with the dust
during strong winds.
In view of these. facts. it is apparent
that sanitary methods should be en-
ployed in controlling the disease.
These should consist in the careful
selection of only sound, healthy pota-
toes for seed. The soil for the hot bed
should be obtained two or three feet
from below the surface after throwing
OF the top layer. or from woods where
there is no possibility that it might he
infested. Healthy slips produced by
these methods, should he planted on
ground where sweet potatoes have
never been grown. or ut least where
the disease has never occurred.
Healthy slips planted on diseased soil
will become diseased. Neither seed
sweet potatoes nor plants should lie
purchased from localities where this
disease is prevalent. The disease will
likely increase each year if sweet, pc.
tatoes arc planted continually on tho
same ground.