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Efficacy of Soil
Insecticides for the Control of Grape
Colaspis, White Grubs, and Wireworms,
in Field Corn in Menard County, Illinois,
2000 |
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John T. Shaw, Michael E. Gray, and
Kevin L. Steffey
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| Summary |
Grape colaspis larvae
and white grubs were numerous at this
experimental site. Wireworms were far
less abundant. Although numerical differences
in grape colaspis larvae were noted
among the treatments, none of the insecticides
were statistically different from the
control. The number of white grubs per
trench was reduced significantly by
several compounds including the following:
Capture 2EC, Force 3G (band), EX-1 seed
treatment, EX-2 seed treatment, Counter
20CR, Aztec 2.1BD, Maxim XL 2.7FS seed
treatment, Regent 4SC, Lorsban 15G (1.9
lb. (AI/acre), Fortress 5G (furrow),
and the ProShield seed treatment. The
number of live plants per trench did
not differ among most insecticide treatments.
By June 28, plant height in the insecticide
plots did not differ statistically from
the control plots. Overall, soil insecticide
performance in this trial was generally
poor for grape colaspis and marginal
for white grubs. Adequate wireworm pressure
was lacking. |
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| Plot Information
and Methods |
Cooperator and
Location
Plots were established on the farm
of Mr. Bob Winkelman near Petersburg
in Menard County, Illinois.
Plot Size
Each insecticide 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 2.1.
Pre-Treatment
Population
In 1999, sticky-trap (Pherocon AM traps)
counts (July 14, 1999) revealed that
grape colaspis adults were abundant
at this experimental site. Soil core
samples also were taken on February
29, 2000, to further ascertain the presence
of grape colaspis larvae. Multiple larval
instars were found on this date reflecting
a considerable range of maturity. No
attempt was made to determine the number
of larvae per sampling unit.
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-in 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 was utilized
for all granular and liquid treatments.
Post-Treatment Evaluations
On May 24 and 25, insect abundance was
estimated by removing a trench of soil
1 meter (length) X 10 centimeters (width)
X 10 centimeters (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). Plant heights were measured on
June 14 and 28 (Table 2.3).
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 MRT test (P=0.05). |
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| Results and
Discussion |
Grape colaspis larvae
and white grubs were numerous at this
experimental site (Table 2.2). Wireworms
were far less abundant and little useful
information was obtained regarding the
efficacy of insecticide treatments for
this insect pest. Although numerical
differences in grape colaspis larvae
were noted among the treatments, none
of the insecticides were statistically
different from the control. This illustrates
the highly variable nature of these
data. The number of white grubs per
trench was reduced significantly by
several compounds including the following:
Capture 2EC, Force 3G (band), EX-1 seed
treatment, EX-2 seed treatment, Counter
20CR, Aztec 2.1BD, Maxim XL 2.7FS seed
treatment, Regent 4SC, Lorsban 15G (1.9
lb AI/acre), Fortress 5G (furrow), and
the ProShield seed treatment.
The number of live plants per trench
did not differ among most insecticide
treatments (Table 2.3). However, significantly
more plants per trench were found in
plots treated with Regent 4SC compared
with control plots. Conversely, significantly
fewer plants were found in plots treated
with a band application of Lorsban 15G
(1.3 lb AI/acre) compared with the control.
On June 14, differences in plant height
were minimal among most treatments;
however, plants were significantly taller
in the Warrior T 1CS treatment compared
with the control. By June 28, plant
height in the insecticide plots did
not differ statistically from the control
plots. Overall, soil insecticide performance
in this trial was generally poor for
grape colaspis and marginal for white
grubs. Adequate wireworm pressure was
lacking.
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 2.1. |
Agronomic
factors and evaluation dates for the
grape colaspis efficacy trial in Menard,
County, Illinois, 2000. |
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|
Variables |
Menard County |
| Planting date
|
May 3, 2000 |
| Hybrid |
NK58 D-1 |
| Plant population
|
28,500 seeds per
acre |
| Row spacing |
30 in |
Soil condition
(top 2-3 inches) |
Moist-dry |
Soil temperature
(4-inch level) |
59oF
|
| Air temperature
|
74oF
|
| Wind |
0-3 mph |
| Previous crop
|
Soybeans |
| Soil insecticides
|
None |
| Fall tillage |
Disc |
| Spring tillage
|
Disc |
| Evaluation dates
|
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| Stand counts |
May 24-25 |
| Plant height |
June 14 and 28 |
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| Table 2.2. |
Mean number of grape
colaspis, grubs and wireworms in one
meter of row for the grape colaspis
efficacy trial, Menard County, Illinois,
2000. |
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|
Treatment |
Rate1 |
Placement |
Number of live
larvae2 |
| Grape
Colaspis |
Grubs |
Wireworms |
| Capture 2EC
|
0.040 |
Furrow |
9.00 |
b |
1.50
|
bc |
0.00
|
a |
| Capture 2EC
|
0.080 |
Furrow |
6.50 |
b |
1.75
|
bc |
0.00
|
a |
| Force 3G |
0.150 |
Furrow |
6.25 |
b |
4.50
|
abc |
0.00
|
a |
| Force 3G |
0.130 |
Band |
9.25 |
b |
2.75
|
bc |
0.25
|
a |
| EX-1 |
seed treatment
|
8.25 |
b |
1.50
|
bc |
0.50
|
a |
| EX-2 |
seed treatment
|
7.50 |
b |
2.00
|
bc |
0.00
|
a |
| Gaucho |
0.500 |
seed treatment
|
8.25 |
b |
3.00
|
abc |
0.25
|
a |
| Counter 20CR
|
1.300 |
Band |
6.75 |
b |
2.25
|
bc |
0.00
|
a |
| Counter 20CR
|
1.300 |
Furrow |
3.50 |
b |
1.75
|
bc |
0.25
|
a |
| Aztec 2.1BD
|
0.150 |
Band |
4.00 |
b |
2.25
|
bc |
0.00
|
a |
| Maxim XL 2.7FS
|
0.060 |
seed treatment
|
3.75 |
b |
1.50
|
bc |
0.00
|
a |
| Maxim XL 2.7FS
+ Adage 5FS |
0.060 0.800
|
seed treatment
|
20.75 |
a |
4.25
|
abc |
0.50
|
a |
| Maxim XL 2.7FS
+ Kernel Guard Supreme |
0.060 |
seed treatment
|
7.50 |
b |
5.25
|
ab |
0.00
|
a |
| Regent 4SC |
0.130 |
Microtube |
6.25 |
b |
2.50
|
bc |
0.25
|
a |
| Force 2829 30CS
|
0.120 |
Microtube |
2.75 |
b |
3.25
|
abc |
0.00
|
a |
| Force 2829 30CS
|
0.120 |
Band |
12.25 |
ab |
3.50
|
abc |
0.25
|
a |
| Warrior T 1CS
|
0.030 |
Band |
10.75 |
b |
4.25
|
abc |
0.00
|
a |
| Lorsban 15G
|
1.300 |
Band |
7.25 |
b |
3.25
|
abc |
0.25
|
a |
| Lorsban 15G
|
1.900 |
Band |
5.00 |
b |
1.75
|
bc |
0.25
|
a |
| Fortress 5G
|
0.160 |
Furrow |
3.25 |
b |
0.50
|
c |
0.25
|
a |
| Gaucho |
1.300 |
seed treatment
|
10.00 |
b |
3.00
|
abc |
0.25
|
a |
| ProShield |
seed treatment
|
8.50 |
b |
1.25
|
bc |
0.00
|
a |
| Control
|
12.50 |
ab |
6.75 |
a |
0.38 |
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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| Table 2.3. |
Number of live plants
in one meter of row, and mean plant
heights for two dates for the grape
colaspis efficacy trial, Menard County,
Illinois, 2000 |
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|
Treatment |
Rate1 |
Placement |
Number of live plants2
|
Plant height (cm)2
|
|
6/14/2000 |
6/28/2000 |
| Capture
2EC |
0.040
|
Furrow |
5.00
|
abc
|
56.38
|
b |
123.19
|
abc
|
| Capture
2EC |
0.080
|
Furrow |
4.00
|
bcd
|
61.17
|
ab
|
127.21
|
abc
|
| Force
3G |
0.150
|
Furrow |
5.25
|
abc
|
62.03
|
ab
|
128.27
|
abc
|
| Force
3G |
0.130
|
Band |
4.25
|
bcd
|
63.25
|
ab
|
123.40
|
abc
|
| EX-1
|
|
seed treatment
|
4.25
|
bcd
|
71.72
|
ab
|
134.62
|
ab
|
| EX-2
|
|
seed treatment
|
5.50
|
abc
|
68.57
|
ab
|
132.08
|
ab
|
| Gaucho
|
0.500
|
seed treatment
|
5.25
|
abc
|
57.97
|
b |
123.19
|
abc
|
| Counter
20CR |
1.300
|
Band |
6.00
|
abc
|
57.67
|
b |
119.59
|
abc
|
| Counter
20CR |
1.300
|
Furrow |
3.50
|
cd
|
68.90
|
ab
|
134.83
|
ab
|
| Aztec
2.1BD |
0.150
|
Band |
6.25
|
abc
|
61.70
|
ab
|
121.07
|
abc
|
| Maxim
XL 2.7FS |
0.060
|
seed treatment
|
4.25
|
bcd
|
62.35
|
ab
|
133.35
|
ab
|
| Maxim
XL 2.7FS + Adage 5FS |
0.060
0.800 |
seed treatment
|
7.25
|
ab
|
62.53
|
ab
|
126.79
|
abc
|
| Maxim
XL 2.7FS + Kernel Guard Supreme
|
0.060 |
seed treatment
|
4.00
|
bcd
|
57.73
|
b |
125.94
|
abc
|
| Regent
4SC |
0.130
|
Microtube |
8.00
|
a |
57.72
|
b |
125.09
|
abc
|
| Force
2829 30CS |
0.120
|
Microtube |
5.75
|
abc
|
61.98
|
ab
|
131.23
|
abc
|
| Force
2829 30CS |
0.120
|
Band |
7.00
|
ab
|
73.00
|
ab
|
125.94
|
abc
|
| Warrior
T 1CS |
0.030
|
Band |
5.50
|
abc
|
75.10
|
a |
131.23
|
abc
|
| Lorsban
15G |
1.300
|
Band |
1.50
|
d |
58.13
|
b |
119.17
|
bc
|
| Lorsban
15G |
1.900
|
Band |
5.00
|
abc
|
57.08
|
b |
114.30
|
c |
| Fortress
5G |
0.160
|
Furrow |
5.00
|
abc
|
66.78
|
ab
|
136.95
|
a |
| Gaucho
|
1.300
|
seed treatment
|
4.75
|
bc
|
63.22
|
ab
|
127.42
|
abc
|
| ProShield
|
|
seed treatment
|
6.25
|
abc
|
61.25
|
ab
|
122.77
|
abc
|
|
Control |
|
|
4.13 |
bcd |
56.87 |
b |
123.93 |
abc |
|
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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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