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Efficacy
of Soil Insecticides for the Control
of Wireworms, White Grubs, and Grape
Colaspis in Field Corn, Logan County,
Illinois, 2000 |
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John
T. Shaw, Michael E. Gray, and Kevin
L. Steffey |
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Summary |
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Despite
the presence of numerous wireworms in
bait stations earlier in the spring,
very few larvae were discovered in this
experimental trial. Even though significantly
fewer live wireworms were observed in
every insecticide treated row compared
with the control, less than two wireworms
were found per meter of row in the check
plots. No significant differences in
the number of dead wireworms per meter
of row were observed among any of the
treatments, including the control plots.
Significantly fewer grape colaspis larvae
were found in most insecticide-treated
rows. Significantly fewer white grubs
were found in all insecticide treated
rows compared with the control plots.
However, overall white grub pressure
also was minimal in this experiment. |
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Plot Information and Methods
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Cooperator and Location
The field used for this insecticide
efficacy trial was obtained with the
help of Mr. Rick Reed of AG Land FS,
Mt. Pulaski, Logan County, Illinois.
Plot Size
Each treatment was applied to a single
row (30-ft long) in each of four replicates.
Experimental Design
A randomized complete block with four
replications was utilized as the experimental
design. Two untreated control plots
were included within each replication.
Data collected from the untreated control
plots were averaged for the analysis
of variance (ANOVA).
Planting
Dates and Agronomic Factors
See Table 3.1.
Pre-Treatment
Population
In late March of 2000, bait stations
were established at the experimental
site and later revealed an infestation
of wireworm larvae. Annual white grubs
also were found in the bait stations
when they were examined in April.
Method of Application for Granules
at Planting Time
Granular insecticides were applied at
planting and metered through computer
controlled SmartBox (SBX) granular applicators
or Noble® units mounted
on each row of an ALMACO®
four-row precision planter. Insecticides
were applied in-furrow or in a 7-inch
band ahead of the firming wheels on
the planter. Spring tines mounted behind
each planter unit were used to incorporate
the insecticide. All rates are specified
as lb. (AI)/acre based on a 30-inch
row spacing.
Method of
Application for Liquids at Planting
time
Regent 4SC and Force WF2829 30CS were
delivered in-furrow at planting through
microtubes calibrated to deliver 2.1
gpa at 30 psi at a speed of 3.0 mph.
Capture 2EC, Force WF2829 30CS, and
Warrior T 1CS were applied through a
single 8003 (flat fan) nozzle in-furrow
or as a band and calibrated to deliver
4.9 gpa at 21 psi at a speed of 3.0
mph.
Seed Treatments
All seed treatments were applied to
NK 58D-1 seed by the respective company.
This same seed variety also was utilized
for all granular and liquid treatments.
Post-treatment Evaluations
On May 23 insect abundance was estimated
by removing a trench of soil 39.4 in.
(1 meter, length) X 4 in. (width) X
4 in. (depth) and counting the number
of insects found. The number of live
plants, grape colaspis larvae, white
grubs, and wireworms were determined
for each trench. Plants were in the
V2 to V3 leaf stage (Ritchie et al.
1993).
Phytotoxicity
Symptoms of phytotoxicity were not observed
for any of the insecticide treatments.
Statistical Analysis
Data were analyzed with the Agriculture
Research Manager (ARM) version 6.1.6,
from Gylling Data Management, Inc.(GDM).
Means were separated by Duncan’s
New Multiple Range Test (P=0.05). |
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Results and Discussion |
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Despite the presence of numerous wireworms
in bait stations earlier in the spring,
very few larvae were discovered in this
experimental trial (Table 3.2). Even
though significantly fewer live wireworms
were observed in every insecticide treated
row compared with the control, less
than two wireworms were found per meter
of row in the check plots. No significant
differences in the number of dead wireworms
per meter of row were observed among
any of the treatments, including the
control plots.
Significantly fewer grape colaspis larvae
were found in most insecticide-treated
rows with only the following exceptions
(Table 3.3): Capture 2EC (band, 0.04
lb. (AI)/acre), EX-1 and EX-2 seed treatments,
Maxim XL 2.7FS + Adage 5FS seed treatment,
Force 2829 30CS, and Gaucho 1.3 mg per
seed.
Significantly fewer white grubs were
found in all insecticide treated rows
compared with the control plots (Table
3.3). However, overall white grub pressure
was minimal in this experiment.
References Cited
Ritchie, S.W., J. J. Hanway, and G.O.
Benson. 1993. How a corn plant develops.
Special Report No. 48, Iowa State University
of Science and Technology, Cooperative
Extension Service, Ames. |
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Table 3.1. |
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Agronomic
factors and evaluation dates of the
wireworm efficacy trial, Logan, County,
Illinois, 2000 |
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Variables |
Logan County |
| Planting
date |
May
3, 2000 |
| Hybrid
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NK58
D-1 |
| Plant
population |
28,500
seeds per acre |
| Row
spacing |
30
inches |
| Soil
condition (top 2-3 inches) |
Moist
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| Soil
temperature (4-inch level) |
62o
F |
| Air
temperature |
73o
F |
| Wind
|
0
— 5 mph |
| Previous
crop |
Soybeans
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| Soil
insecticides |
None
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| Fall
tillage |
None
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Spring
tillage
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Disc
once |
| Evaluation
dates |
May
23, 2000 |
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Table 3.2. |
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Mean
number of live and dead wireworms in
one meter of row, Logan County, Illinois,
2000. |
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Treatment |
Rate1 |
Placement |
Number of wireworms2
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Live |
Dead |
| Capture
2EC |
0.04
|
furrow
|
0.00 |
b
|
0.75 |
a
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| Capture
2EC |
0.08
|
furrow
|
0.50 |
b
|
0.75 |
a
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| Capture
2EC |
0.04
|
band
|
0.25 |
b
|
0.25 |
a
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| Capture
2EC |
0.08
|
band
|
0.50 |
b
|
0.00 |
a
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| Force
3G |
0.15
|
furrow
|
0.00 |
b
|
0.50 |
a
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| Force
3G |
0.13
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band
|
0.00 |
b
|
0.50 |
a
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| EX-1
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seed
treatment |
0.25 |
b
|
0.00 |
a
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| EX-2
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|
seed
treatment |
1.00 |
b
|
0.25 |
a
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| EX-3
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|
seed
treatment |
0.25 |
b
|
0.00 |
a
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| Counter
20CR |
1.30
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furrow
|
0.25 |
b
|
0.75 |
a
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| Aztec
2.1BD |
0.15
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band
|
0.50 |
b
|
0.50 |
a
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| Maxim
XL 2.7FS |
0.06
|
seed
treatment |
0.25 |
b
|
0.00 |
a
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| Maxim
XL 2.7FS + Adage 5 FS |
0.06
0.80 |
seed
treatment |
0.75 |
b
|
0.25 |
a
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| Maxim
XL 2.7FS + Kernel Guard Supreme
|
0.06
1.80 |
seed
treatment |
0.25 |
b
|
0.00 |
a
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| Regent
4SC |
0.13
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microtube
|
0.50 |
b
|
0.25 |
a
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| Force
2829 30CS |
0.12
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band
|
0.25 |
b
|
0.25 |
a
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| Warrior
T 1CS |
0.03
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band
|
0.25 |
b
|
0.25 |
a
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| Lorsban
15G |
1.30
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band
|
0.25 |
b
|
1.00 |
a
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| Lorsban
15G |
1.30
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furrow
|
0.00 |
b
|
0.75 |
a
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| ProShield
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seed
treatment |
0.25 |
b
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0.50 |
a
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| Gaucho
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1.30
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seed
treatment |
0.25 |
b
|
0.25 |
a
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| Fortress
5G |
0.16
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furrow
|
0.00 |
b
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0.00 |
a
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Control |
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1.88 |
a |
0.00 |
a |
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1Rates are specified
as lb (AI)/acre.
2Means in a column followed
by the same letter are not significantly
different (P=0.05; Duncan’s New
MRT) |
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Table 3.3. |
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Mean
number of grape collapses and grubs
in one meter of row for the wireworm
efficacy trial, Logan County, Illinois,
2000 |
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Treatment |
Rate1 |
Placement |
Number of live larvae2
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Grape colaspis |
Grubs |
| Capture
2EC |
0.040 |
furrow
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0.00 |
c
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0.00 |
b
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| Capture
2EC |
0.080 |
furrow
|
0.75 |
c
|
0.00 |
b
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| Capture
2EC |
0.040 |
band
|
1.25 |
abc
|
0.50 |
b
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| Capture
2EC |
0.080 |
band
|
0.50 |
c
|
0.25 |
b
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| Force
3G |
0.150 |
furrow
|
0.50 |
c
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0.25 |
b
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| Force
3G |
0.130 |
band
|
0.50 |
c
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0.00 |
b
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| EX-1
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seed
treatment |
3.00 |
ab
|
0.25 |
b
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| EX-2
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|
seed
treatment |
1.50 |
abc
|
0.25 |
b
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| EX-3
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|
seed
treatment |
0.50 |
c
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0.00 |
b
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| Counter
20CR |
1.300 |
furrow
|
0.00 |
c
|
0.00 |
b
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| Aztec
2.1BD |
0.150 |
band
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0.50 |
c
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0.00 |
b
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| Maxim
XL 2.7FS |
0.060 |
seed
treatment |
0.75 |
c
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0.25 |
b
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| Maxim
XL 2.7FS + Adage 5 FS |
0.060 0.800 |
seed
treatment |
1.50 |
abc
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0.25 |
b
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| Maxim
XL 2.7FS + Kernel Guard Supreme
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0.060 1.800 |
seed
treatment |
1.00 |
bc
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0.00 |
b
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| Regent
4SC |
0.130 |
microtube
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0.25 |
c
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0.00 |
b
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| Force
2829 30CS |
0.120 |
band
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1.50 |
abc
|
0.00 |
b
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| Warrior
T 1CS |
0.030 |
band
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1.00 |
bc
|
0.00 |
b
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| Lorsban
15G |
1.300 |
band
|
1.00 |
bc
|
0.50 |
b
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| Lorsban
15G |
1.300 |
furrow
|
0.25 |
c
|
0.50 |
b
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| ProShield
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|
seed
treatment |
0.00 |
c
|
0.00 |
b
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| Gaucho
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1.300 |
seed
treatment |
1.25 |
abc
|
0.75 |
b
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| Fortress
5G |
0.160 |
furrow
|
1.00 |
bc
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0.25 |
b
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Control |
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3.13 |
a |
1.75 |
a |
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1Rates are specified as
lb (AI)/acre, except for seed treatments
which are expressed as mg/seed.
2Means in a column followed
by the same letter are not significantly
different (P=0.05; Duncan’s New
MRT) |
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