2007 Extension Research Report
Insect Management
CONTROL OF CATERPILLAR PESTS OF COLLARDS WITH FOLIAR
INSECTICIDES
Alton N. Sparks, Jr., University of Georgia Cooperative Extension, Department of Entomology
Tifton, GA 31793, asparks@uga.edu
through visual inspection of five randomly
selected plants per plot on each sample date.
Larvae were classified and counted by species or
classified and counted as ‘small’ if they were too
young (small) for easy identification in the field.
Data were recorded (and reported) as number of
larvae/five plants. Larval densities were analyzed
with the PROC ANOVA procedure of PC-SAS.
Where significant differences were detected (P<
0.05), means were separated with LSD (P=0.05).
Introduction
Caterpillars are the primary pests of
Brassica crops in Georgia. Numerous species can
be found on these crops, with the most frequent
species in south Georgia being the diamondback
moth, cabbage looper and imported cabbageworm.
As key pests of these crops, insecticidal control is
frequently required and knowledge of the relative
efficacy of insecticides against these pests is
necessary for proper insecticide selection.
Additionally, the potential for insecticide
resistance, particularly in the diamondback moth,
requires periodic re-evaluation of efficacy of
registered insecticides for these pests. This test
evaluated the efficacy of selected insecticides
against the common caterpillar pests on collards.
Results and Discussion
Pest pressure was heavy during this test
with fairly consistent pest pressure from
diamondback moth and high densities of imported
cabbageworm on one sample date (Table 1). All
treatments evaluated provided significant control
of diamondback moth, with minor differences
among the insecticide treatments; however, none
of the treatments were able to maintain
diamondback moth populations below 1 per 5
plants. All insecticide treatments showed good
efficacy against loopers, with the possible
exception of Tesoro. This product has shown
reduced efficacy against loopers in prior tests. All
of the insecticides also provided significant
reductions in imported cabbageworm.
Trends among treatments did show
consistently (but not significant) higher
diamondback moth and looper larval densities in
the BAS 320 treatment. This has been observed in
prior tests and is assumed to be related to short
residual activity. BAS 320 performed similar to
other products in this test, which has not always
been the case in prior tests which were conducted
without a surfactant. While not directly evaluated,
addition of the surfactant did appear to aid the
efficacy of BAS 320 I.
Materials and Methods
A small plot trail was conducted at the
UGA Tifton Campus Horticulture Farm in Tifton,
Georgia. Collards were transplanted into single
row plots on a six foot bed. Plots measuring one
row (assumed 36 inch for application of
treatments) by 18 feet were established in a
randomized complete block design with four
replications. Treatments evaluated were: SpinTor
2SC at 4 oz/ac, Avaunt 30WDG at 3.5 oz/ac,
Proclaim 5SG at 3.2 oz/ac, Rimon 0.83EC at 12
oz/ac, Tesoro 4EC at 6.4 oz/ac, and BAS 320
(2SC) at 16 oz/ac. A non-treated control was also
included. All insecticide treatments were tank
mixed with Penetrator Plus at 0.5% by volume.
Insecticide treatments were applied with a CO2
pressurized backpack sprayer (60 PSI), in a total
volume of 40 gpa with 3 hollow-cone nozzles per
row (one over-the-top; two on drops). Treatments
were applied on 19 and 25 May and 1 June, 2006.
Caterpillar densities were monitored
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Table 1. Larval densities, efficacy trial in collards, UGA Hort. Farm, Tifton, GA, 2006.
Larvae per 5 plants
Treatment
23 May
30 May
2 June
5 June
Diamondback moth larvae
Check
9.0 a
36.0 a
31.5 a
14.0 a
BAS 320 I
2.0 b
4.8 b
9.3 b
5.0 b
Rimon
2.3 b
3.3 b
4.5 b
3.8 bc
Tesoro
1.0 b
0.5 b
4.0 b
3.3 bc
Avaunt
3.3 b
4.3 b
4.5 b
2.0 bc
Proclaim
0.8 b
0.8 b
3.5 b
1.3 c
SpinTor
2.8 b
2.0 b
2.0 b
1.0 c
Check
0.8 a
1.5 a
3.3 a*
2.0 a
BAS 320 I
0.0 a
0.3 a
0.5 a
0.3 b
Rimon
0.0 a
1.0 a
0.5 a
0.0 b
Tesoro
0.0 a
0.8 a
0.8 a
1.0 ab
Avaunt
0.0 a
0.3 a
0.0 a
0.0 b
Proclaim
0.0 a
0.3 a
0.5 a
0.0 b
SpinTor
0.0 a
0.5 a
0.0 a
0.0 b
Cabbage looper larvae
Imported cabbageworm larvae
Check
0.5 a
21.3 a
9.3 a
3.8 a*
BAS 320 I
0.0 a
2.5 b
3.3 b
1.0 a
Rimon
0.3 a
1.5 b
1.0 b
0.5 a
Tesoro
0.0 a
1.8 b
1.5 b
1.3 a
Avaunt
0.0 a
0.5 b
0.5 b
0.3 a
Proclaim
0.0 a
0.8 b
0.3 b
0.3 a
SpinTor
0.0 a
0.0 b
0.0 b
0.0 a
Numbers within columns followed by the same letter are not significantly different (LSD; P=0.05). *
Differences were detected at P<0.1.
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