The Idaho Republican. [volume] (Blackfoot, Idaho) 1904-1932, 1920-08-11
BEET MEN FIGHT AGAINST
DISEASE CARRYING HOPPER

BOISE.-Curley top is present
again this year in Idaho sugar beet
fields, according to Claude Wake
land, entomologist of the University
OF Idaho extension division, who says
the disease is transmitted from plant
to plant by a diminutive insect
known as the sugar beet leaf hopper.
He gives instructions for control
measures in the following state
] ment:
"The general appearance and eff
feet of curley top in sugar beets is
well known to most of the sugar
growers of our state. Each year
it makes it's appearance in varying
degree in many localities, and this
year is no exception. An affected
beet plant, when first noted, shows
wrinkling or curling of the inner
leaves, and as the disease develops
it may spread to the entire plant.
The elayes may become badly wrin-
killed. or curled, the roots may become
stunted and develop an abnormally
large number of root fibers, while
the main root often becomes dark
ened.
This disease and it's effects have
been known for many years, but lit
tie is known regarding the organism
that causes it. 1t has been proven
by investigation that curley top is
transmitted from diseased plant
to those that are healthy by small
insects known as sugar beet leaf
hoppers. These insects when fully
grown are only about an eighth of
an inch in length and creamy white
in color. They are SO small and &C
tive that they easily escape atten-
ton in the field and are rarely seen
unless special observations are made.
They are strong hoppers and can
leap distances many times their own
length. They are provided with
strong, sharp beak which they in
sert into the plant tissues and
through which they extract plant
juices.
'"In feeding, leaf hoppers may at
tack many different plants. The dis
ease is supposed to be transmitted by
being carried from an affected plant
to healthy one by means of sugar
beet leaf hoppers. 1t has been prov
en- that leaf hoppers which have not
already fed on diseased plants can
not cause disease. 1t is also def
nitely known that where but a single
leaf hopper has fed on a diseased
plant, this plant will develop the
curly leaf disease.
There is no method known
whereby curly top can be prevent;
ed. There are, however, certain es-
tablished facts, which, if observed
by the grower, will greatly aid in re-
ducing the losses that leaf hoppers
cause from an affected plant and
since certain weeds and other plants
besides beets are hosts of the disease
organism, it can readily be seen that
keeping weeds down will greatly les
sen the sources of infection. Since
beet fields are plowed each fall, dis
eased plants do not live over, and
it would appear that the main
source Of continued infestation is in
diseased plants other than beets.
Clean cultural methods, not only in
beet fields, but in the fields sur
rounding them, should be practiced
carefully.
Clean culture will further reduce
the numbers of alternating leaf hop
pers by destroying their protection.
ut is very important that beet
fields be given sufficient water to
keep them growing rapidly and to
prevent leaves from willing. Beets |
with plenty of moisture in the soil
will show less willing than when al
lowed to become dry, and where |
drainage conditions are as they |
should be, water can be applied plen
tifully and with the result that a
bigger and better yield will be pro-
duced and diseased plants will not |
be affected SO badly as where they |
are caused to wilt and their growth |
is checked by lack of sufficient |