Spring migrant green peach aphid control on peach and apricot with systemic insecticides and resultant residues


Powell, D.M.; Maitlen, J.C.; Mondor, W.T.

Journal of Economic Entomology 71(2): 192-194

1978


February soil injection and soil drenching with soluble concentrate oxydemetonmethyl and soil injection with granular aldicarb and April application of foliar sprays of exydemetonmethyl gave excellent control of Myzus persicae (Sulzer) on peaches. April applications of soil treatments were not as effective. No residues of oxydemetonmethyl were detected in harvest peaches or apricots treated by foliar application or in peaches treated with the soil drench application. However, residues of oxydemetonmethyl were detected in apricots from the soil drench application and in peaches and apricots from the soil injection application.

Spring
Migrant
Green
Peach
Aphid:'
Control
on
Peach
and
Apricot
with
Systemic
Insecticides
and
Resultant
Residues'
D.
M.
POWELL,
J.
C.
MAITLEN,
and
W.
T.
MONDOR
Yakima
Agricultural
Research
Laboratory,
Agric.
Res.
Serv.,
USDA,
Yakima,
WA
98902
ABSTRACT
February
soil
injection
and
soil
drenching
with
soluble
concentrate
oxydemetonmethyl
and
soil
injection
with
granular
aldicarb
and
April
application
of
foliar
sprays
of
exydemetonmethyl
gave
excellent
control
of
Myzus
persicae
(Sulzer)
on
peaches.
April
applications
of
soil
treatments
were
not
as
effective.
No
residues
of
oxy-
demetonmethyl
were
detected
in
harvest
peaches
or
apri-
cots
treated
by
foliar
application
or
in
peaches
treated
with
the
soil
drench
application.
However,
residues
of
oxydemetonmethyl
were
detected
in
apricots
from
the
soil
drench
application
and
in
peaches
and
apricots
from
the
soil
injection
application.
The
green
peach
aphid,
Myzus
persicae
(Sulzer)
,
is
the
major
vector
of
the
potato
leafroll
virus
(PLRV)
and
several
other
viruses
of
agricultural
crops.
The
PLRV
causes
leafroll
in
the
plants
and
a
phloem
necrosis
in
the
tubers
of
the
'Russet
Bur-
bank'
potato
and
results
in
millions
of
dollars
in
crop
loss
annually.
In
Washington,
the
aphid
passes
the
winter
in
the
egg
stage
lodged
beneath
buds
on
peach
trees
and,
after
leaving
peach,
acquires
the
PLRV
from
infected
potato
plants.
Powell
and
Mondor
(1976)
reported
on
spraying
peach
trees
for
area
control
of
the
green
peach
aphid.
They
found
that
trees
had
to
be
sprayed
between
Apr.
1
and
May
1,
after
the
overwintering
eggs
hatched,
but
before
the
aphids
developed
wings
and
migrated
from
the
trees
to
the
summer
host
plants.
However,
during
this
time,
wind
limited
the
spray-
ing
operation
to
early
morning
or
late
evening
for
1-2
days/wk.
If
an
effective
systemic
insecticide
could
be
applied
instead
as
a
soil
injection
or
soil
drench,
the
treatment
season
could
begin
in
Feb.,
and
ap-
plications
could
be
made
at
any
hour.
Therefore,
we
tested
the
effectiveness
of
early
season
soil
ap-
plications
of
2
systemic
insecticides,
oxydemeton-
methyl
and
aldicarb,
to
peach
and
apricot
trees
in
Washington.
We
also
report
on
residue
of
oxyde-
metonmethyl
found
in
fruit
at
harvest.
The
tests
took
place
at
Yakima
and
Wenatchee
in
1975
and
at
Yakima
alone
in
1976
and
1977.
MATERIALS
AND
METHODS.
—In
the
1975
tests
at
Yakima,
oxydemetonmethyl
soluble
concentrate
(SC)
was
applied
as
a
soil
drench,
soil
injection,
and
foliar
spray
to
peach
and
apricot
trees.
At
We-
natchee,
the
chemical
was
applied
only
to
peach
trees
but
by
the
same
3
methods.
In
the
1976
and
1977
tests
at
Yakima,
both
oxydemetonmethyl
SC
and
aldicarb
15
G
were
applied
by
soil
injection
to
peach
trees,
and
oxydemetonmethyl
SC
was
ap-
plied
by
soil
drench
as
well.
The
oxydemetonmethyl
soil
drenches
were
applied
on
a
per
tree
basis
at
a
rate
of
7
g
AI
in
1975
and
1
Hemiptera
(Homoptera):
Aphididae.
3
This
paper
reports
the
results
of
research
only.
Mention
of
a
pesticide
does
not
constitute
a
recommendation
for
use
by
the
USDA,
nor
does
it
imply
registration
under
FIFRA
as
amended.
Also,
mention
of
a
proprietary
product
does
not
constitute
an
endorsement
by
the
USDA.
Received
for
publica-
tion
Oct.
3,
1977.
1976
and
10
g
AI
in
1977
in
11.4
liters
of
water/2.54
cm
of
trunk
diam
(TD);
then
ca.
114
liters
of
water
was
poured
around
each
tree.
The
oxydemeton-
methyl
soil
injections
were
applied
as
a
1:1
mixture
with
water
at
the
same
rates
of
AI/2.54
cm
TD.
The
oxydemetonmethyl
foliar
spray
was
applied
to
the
point
of
runoff
at
a
rate
0.37
g
AI/liter
of
water.
The
granular
aldicarb
was
applied
on
a
per
tree
basis
at
a
rate
of
4
g
AI
in
1976
and
10
g
AI
in
1977
per
2.54
cm
TD.
The
oxydemetonmethyl
and
aldicarb
soil
injection
treatments
were
applied
in
two
15.2
cm
deep
holes/2.54
cm
TD
and
no
ad-
ditional
water
was
added.
The
soil
drench
and
soil
injection
treatments
were
placed
ca.
1-2
m
from
the
base
of
the
tree
in
1975
and
1976,
and
ca.
0.5
m
from
the
base
of
the
tree
in
1977.
Single
tree
plots
replicated
3
times
were
used
in
a
randomized
com-
plete
block
design.
The
tree
TD
averaged
15.2
cm.
To
analyze
residues
of
oxydemetonmethyl,
we
picked
12-24
peaches
or
10-30
apricots
at
random
from
each
tree.
The
samples
were
stored
in
a
freezer
until
analysis.
Just
before
analysis,
the
samples
were
diced
while
still
frozen
into
0.3-
to
0.6
-cm
cubes.
Then
100-g
subsamples
were
extracted
according
to
the
procedures
of
Thornton
and
Olson'.
Measured
portions
of
the
extracts
were
evaporated
to
dryness
in
a
40°C
water
bath
with
the
aid
of
a
gentle
stream
of
air.
Residues
of
oxydemetonmethyl
were
then
oxidized
to
the
sulfone
metabolite
by
the
method
of
Thornton
and
Olson'.
The
2
substances,
oxydemetonmethyl
and
its
sulfone
metabolite,
were
analyzed
as
1
com-
bined
compound
with
an
Aerograph®
Model
600
gas
chromatograph
and
an
attached
Melpar®
fl
ame
photometric
detector
equipped
with
a
526-miL
fi
lter
for
the
determination
of
phosphorous
compounds.
The
91.44x0.32
-cm
OD
glass
column
was
packed
with
Gas
Chrom®
Q
(80/100
mesh)
coated
with
6%
DC
-200
and
operated
at
175°C
with
a
nitrogen
fl
ow
rate
of
80
ml/min.
We
did
the
analysis
without
cleaning
the
plant
extracts
and
verified
the
reliability
of
the
analytical
method
by
fortifying
control
sam-
192
3
Thornton,
J.
S.,
and
T.
J.
Olson.
1971.
Determination
of
Meta-Systox-R®
residues
in
lettuce
and
sugar
beets
by
thermionic
emission
gas
chromatography.
Report
No.
21000,
Chemagro,
a
Division
of
Baychem
Corporation,
Research
and
Development
Department,
P.
0.
Box
4913,
Kansas
City,
MO
64120.
12
pp.
Apri11978
POWELL
ET
AL.:
CONTROL
OF
GREEN
PEACH
APHID
ON
PEACH
193
Table
1.
-Control
of
the
green
peach
aphid
on
peach
trees
with
oxydemetonmethyl,
1975.*
Method"
Aphids/10
peach
twigs'
Aphids/
10
peach
leaves"
Rate
Apr.
May
May
(g/AI)
29
16
22
June
4
Foliar
spray
Soil
drench
Soil
in-
jection
Untreated
0.37/liter
6.3
a
7
a
2
a
0.3
a
7/2.54
cm
TD
401
b
575
b
516
b
39.6
b
7/2.54
cm
TD
322
b
664
b
554
b
69.0
c
369b
1227c
516b
87.0c
Means
followed
by
the
same
letter
are
not
significantly
differ-
ent
at
the
5%
level.
"All
treatments
were
applied
Apr.
9.
a
Each
tree
was
visually
examined
for
evidence
of
aphid
in-
fested
peach
twigs,
and
10
such
twigs/tree
were
collected,
and
the
number
of
aphids
on
the
twigs
were
counted.
All
infested
twigs/tree
were
collected
from
trees
with
less
than
10
infested
twigs,
and
the
remainder
of
the
twigs
were
collected
at
random.
Ten
leaves
were
collected/infested
twig
or
a
maximum
of
20
leaves/tree.
pies
of
peaches
and
apricots
with
varying
amounts
of
oxydemetonmethyl
and
its
sulfone
and
by
then
determining
the
percentage
recovery.
TESTS
AND
RESULTS.
-
1975
Tests
at
Yakima.
-
On
Apr.
9,
when
the
peach
trees
were
in
the
large
bud
stage
and
apricot
trees
in
the
bloom
stage,
we
treated
peach
and
apricot
trees
in
a
10-yr-old
orchard
with
oxydemetonmethyl
by
all
3
methods
of
application.
The
trees
were
examined
for
aphids
on
Apr.
29,
May
16
and
22.
The
foliar
spray
of
oxydemeton-
methyl
gave
excellent
control
of
the
aphids
on
peach
trees.
However,
the
soil
drench
and
soil
injection
treatments
were
not
effective,
probably
because
suf-
ficient
time
was
not
allowed
for
enough
material
to
be
translocated
to
the
developing
peach
leaves
to
kill
the
aphids
(Table
1)
.
Only
a
few
aphids
were
found
on
the
apricots,
and
data
were
omitted.
The
avg
recoveries
of
oxydemetonmethyl
from
peaches
and
apricots
treated
at
rates
ranging
from
1.0
to
0.1
ppm
were
94.0%
(80.0-110.8)
and
97.0%
(85.7-103.7)
,
respectively.
The
avg
recoveries
of
oxydemetonmethyl
sulfone
from
peaches
and
apricots
were
97.4%
(74.7-120.0)
and
101.2%
(80.0-113.3),
respectively.
Oxydemetonmethyl
residues
were
not
detectable
in
apricots
treated
by
foliar
spray,
but
amounts
found
in
the
3
replicates
of
the
soil
drench
treatment
were
0.03,
0.04,
and
0.03
ppm,
and
values
for
the
soil
injection
treatment
were
0.10, 0.59,
and
0.96
ppm.
Oxydemetonmethyl
residues
were
not
detectable
in
peaches
treated
by
foliar
spray
or
soil
drench,
but
amounts
found
in
the
3
replicates
of
the
soil
injec-
tion
treatment
were
0.12,
0.06,
0.09
ppm.
Thus,
oxydemetonmethyl
residues
in
apricots
from
the
soil
injection
treatment
were
higher
than
the
residues
in
peaches
from
the
same
application,
prob-
ably
because
of
the
shorter
interval
between
treat-
ment
and
harvest,
105
days
for
apricots
and
152
days
for
peaches.
Also,
residues
in
apricots
from
the
soil
drench
application
were
detectable,
whereas
no
resi-
dues
were
found
in
peaches
exposed
to
the
same
application.
Here
again,
the
interval
between
treat-
ment
and
harvest
probably
was
responsible.
1975
Test
at
Wenatchee.
-We
applied
oxydemeton-
methyl
on
Apr.
9
by
all
3
methods
of
treatment
to
peach
trees.
Aphids
and
infested
twigs
were
counted
Apr.
10,
28,
and
June
10.
No
aphids
were
found
on Apr.
10,
but
on
Apr.
28,
the
no.
of
aphids/10
peach
twigs
for
the
foliar
spray,
soil
drench,
soil
injection,
and
untreated
plots
were
4,
48,
35,
and
18,
respectively;
on
June
10,
the
no.
of
aphids/10
peach
leaves
was
0.2,
4.0, 4.2,
and
7.5,
respectively.
Oxydemetonmethyl
residues
in
fruit
from
the
foliar
spray
and
soil
drench
treatments
were
not
detectable,
but
residues
were
found
in
the
fruit
from
the
soil
injection
treatment
at
levels
of
0.12,
0.06,
and
0.09
ppm.
1976
Test
at
Yakima.
-We
applied
both
oxyde-
metonmethyl
and
aldicarb
to
peach
trees
in
the
same
10-yr-old
orchard.
The
oxydemetonmethyl
was
ap-
plied
by
both
soil
drench
and
soil
injection
on
Feb.
19,
and
the
aldicarb
was
injected
in
granular
form
on
Feb.
23.
We
examined
the
trees
for
aphids
on
Apr.
22,
May
5,
20,
and
June
2.
Applications
of
oxydemetonmethyl
and
aldicarb
by
soil
injection
gave
excellent
control
of
the
aphids
and
prevented
the
development
of
winged
aphid
spring
migrants
(Table
2).
The
soil
injection
treat-
ments
greatly
reduced
colonization
by
stem
mothers.
However,
several
twigs
that
showed
evidence
of
aphid
colonization
(leafcurling,
honey
dew,
and
exuviae)
had
no
aphids
on
the
leaves.
Apparently,
the
con-
centration
of
the
systemic
insecticide
in
the
develop-
ing
peach
leaves
was
not
great
enough
to
kill
all
stem
mothers,
thus
aphid
colonization
occurred
(Table
2,
May
20),
but
the
concentration
of
in-
secticide
increased
in
the
developing
leaves
in
amounts
high
enough
to
kill
the
young
aphids
before
wing
development
occurred
and
spring
migration
of
aphids
began.
Twigs
that
showed
evidence
of
Table
2.
-Control
of
the
green
peach
aphid
on
peach
trees
with
oxydemetonmethyl
and
aldicarb,
1976.
Aphids/
twig"
Aphids/
leaf"
Infested
twigs/
tree'
Treatment°
Apr.
22
May
5
May
20
May
20
June
2
Oxydemetonmethyl
injection
0.6
0.3
0.6
a
2.0
0.6
Aldicarb
injection
0.6
0
3.4
b
7.0
3.3
Oxydemetonmethyl
drench
1.3
0
17.6
c
24.0
13.0
Untreated
.6
.3
29.9
d
11.8
9.0
Oxydemetonmethyl
soil
drench
or
soil
injection
at
7
g
AI/
2.54
cm
TD
(0.25
oz
AI/in.
TD)
were
applied
Feb.
19,
and
aldi-
carb
at
4
g
AI/2.54
cm
TD
(0.14
oz
AI/in.
TD)
was
applied
Feb.
23.
"Ten
peach
twigs/tree
were
collected
at
random.
°
Collected
2
peach
leaves/infested
twig/tree
and
counted
all
aphids
on
the
leaves.
d
Means
followed
by
the
same
letter
are
not
significantly
differ-
ent
at
the
5%
level.
a
Counted
all
peach
twigs
showing
evidence
of
aphid
infestation.
194
JOURNAL
OF
ECONOMIC
ENTOMOLOGY
Vol.
71,
no.
2
Table
3.
-Control
of
green
peach
aphid
on
peach
trees
with
oxydemetonmethyl
and
aldicarb,
1977.°
Treatment°
Infested
Aphid
twigs/
count'
treed
Apr.
27
May
23
Aldicarb
granular
injection
0.0
a
Oxydemetonmethyl
soil
injection
1.0
ab
Oxydemetonmethyl
soil
drench
2.0
ab
Untreated
13.3
b
3.0
b
0
a
0
a
9.0
c
4
Means
followed
by
the
same
letter
are
not
significantly
differ-
ent
at
the
5%
level.
b
The
insecticides
were
applied
on
Feb.
9
at
the
rate
of
lOg
AI/2.54
cm
TD.
Aphids
collected
on
a
beating
board
at
3
locations/tree.
d
The
counter
was
located
10
m
from
the
base
of
the
tree,
and,
with
the
aid
of
8X30
magnification
fi
eld
glasses,
searched
one
side
of
the
tree
and
counted
the
no.
of
peach
twigs
showing
evidence
of
aphid
infestation.
This
procedure
was
repeated
on
the
other
side
of
the
tree.
aphid
infestation
on
May
20
did
not
show
evidence
of
aphid
infestation
by
June
2
(Table
2)
.
Residues
of
oxydemetonmethyl
and
its
sulfone
metabolites
were
detected
in
harvested
peaches
from
the
soil
injection
application
only.
The
amounts
found
were
0.03
and
0.07
ppm
for
2
of
the
3
repli-
cates;
residues
in
the
3rd
replicate
were
not
detect-
able.
1977
Tests
at
Yakima.
-On
Feb.
9,
we
applied
the
same
insecticides
as
in
1976
but
placed
the
material
closer
to
the
base
of
the
trees
and
increased
the
rate
to
10
g
AI/2.54
cm
TD.
The
application
of
oxydemetonmethyl
and
gran-
ular
aldicarb
by
soil
injection
again
gave
excellent
control
of
aphids
(Table
3)
.
Application
of
oxyde-
metonmethyl
by
soil
drench,
when
placed
closer
to
the
tree
trunk,
was
more
effective
than
when
placed
1-2
m
from
the
tree.
DiscussIoN.-Soil
injection
applications
in
Feb.
1976
and
1977
provided
enough
time
(45-50
days)
for
the
systemic
insecticides
to
translocate
to
the
peach
buds
and
developing
leaves
in
concentrations
great
enough
to
kill
the
hatching
stem
mothers
and
young
aphids.
Also,
the
longer
interval
between
treatment
and
harvest
(206
days
-1976)
produced
slightly
lower
resides
than
the
Apr.
1975
treatment,
which
had
a
152
-day
interval
between
application
and
harvest.
REFERENCE
CITED
Powell,
D.
M.,
and
W.
T.
Mondor.
1976.
Area
control
of
the
green
peach
aphid
on
peach
and
the
reduction
of
potato
leafroll
virus.
Am.
Potato
J.
53:
123-39.