The Filer record. (Filer, Idaho) 1919-1930, 1921-11-24
BEET HOPPER CAUSES
BIG SUGAR BEET LOSS
RY EARL wooLRIDGE


munity have considerable trouble IN
getting yields OF sugar beefs and
few failed 20 gef any crop al all.
Ralph Smith. field entomoligist
Tor tho state. visited the high school
some time ago and went over several
sugar beet fields with the agricul.
tnral classes lie showed that. With
out doubt the trouble with the sugar
beets. was due 10 small fly. called
the sugar beet leaf hopper. which
causes the disease known as curly
top.
On careful examination. these flies
may be seen by the dozen. on and ar
ound the beet tops. The fully ma
rured leaf hopper IS about one-eighth
Of an inch long. and with the exeep-
ton OF the eyes. IS OF light creamy
white color. They are SO exceedingly
small and active that they are very
difficult 10 observe in the field ex-
cept as they ny from plant 10 plant
This tiny Fly begins 10 deposit It's
vi. eggs in the stems and mid
ribs OF beet leaves from about the
md Of June until the end OF August
Probably the majority OF the eggs
are deposited BY the middle OF July
The nymphs or young flies begin TO
appear about the second week in Ju-
~ and sometimes in Idaho as late as
he end OF August Slit-like scars
are prouced on the beet stems where
The eggs have been deposited some
lines these ovipository scars are
very numerous and conspicuous The
egg stage appears TO be about fifteen
1ays and the young insects reach
he adult stage In about twenty days
more The adults hibernate on
weeds aud brush and resume their
tctIyity The following spring
The SYMPTOMS OF injury By this leaf
hopper are to be found upon all parts
of the plant. The first 10 appear 3
usually an inward curling OF the In
ner leaves. This Is associated with
a distortion and enlargement OF the
veins OF the leaf. In severe cases
the veins are covered with nipple
like protuberances. Al the disease
advances the whole plant becomes /
afflicted. The leaves become badly /
srumpIed. the stunted roots develop /
IN abnormally large number OF IL /
hrous rootiets from the root seams /
lnd the root itself becomes darkened Z
specially where the rings OF fibro- Z
vascular bundles show in cross sec
lions on cutting through a beet 1
-ross-wise the cut surface plainl, 1
hows several dark rings. one inside /
the other The crown OF the beet I
~ill often be covered with a sweet. /
summy substance which exrides (
rom the beet.
IN SEINE way. not at present un
ierstood. certain so-caiied viraleni 1
leaf hoppers have the power OF pro
iucing curly tops In healthy beets 4
single individual which possesses
his power will infect healthy plant
II confined upon IL for five minutes
Normal individuals do not have the
power 10 cause the disease. II has
been demonstrated quite recently
that before a sugar beet leaf hopper
can transmit curly top il must itself
become innoeulated BY feeding upon
a diseased plant. There seem to b.
many points In common between ths
carrying OF curly top by these Leaf
hoppers and the relation existing be
fwen certain mosquitoes and maiaria
fever transmission The micro-or.
sanism which j. now supposed to b.
he real cause OF the disease must b.
taken up by the leaf hopper while
.eeding on q diseased plant and then
transmitted TO healthy plants durinE
he process OF feeding upon them.
There Is very little 10 be said 70
sarding the control Of this insect. In
act. there is no known method BY
which curly top can be prevented.
rhe practice OF clean culture and the
and burning over OF all pos
.ible hybernafing places is always g.
be- recommended. but even this b.
rot sufficient There are cases
xhere early planting prevented in
Jury. This does not seem n be
sure remedy in an localities. how
.ver n