2007 Extension Research Report
Insect Management
EVALUATION OF INSECTICIDE TREATMENTS IN CABBAGE I
David G. Riley, University of Georgia, Tifton Campus, Department of Entomology, Tifton, GA 31793,
dgr@uga.edu
Introduction
Cabbage, Brassica oleracea (L.), is our
main Brassica crop in Georgia. It is faced with
multiple pests that attack the leaves and head each
year, namely, diamondback moth (DBM); Plutella
xyllostella, cabbage looper (CL); Trichoplusia ni,
imported cabbage worm (ICW); Pieris rapae,
tobacco thrips Frankliniella fusca and aphids;
Myzus sp. The test evaluated some of the newest
products labeled and not yet available for this
crop. It also looked at insecticide rotations which
will be critical in the management of insecticide
resistance in DBM.
Results and Discussion
Diamondback moth was the most
prevalent and most damaging of the Lepidoptera
pests in this test. The treatments that controlled
total Lepidoptera larvae ranked from the best were
treatments 6, 4, 3, 2, 7, and 5, respectively. These
indicated that all of the insecticide treatments
except Warrior alone provided significant control
of this pest group. The best treatment (1) was a
combination, but the rotations, particularly
treatment 4, also did very well. The treatments
that provided the most protection to damage to the
cabbage head were treatments 7, 6, 4, 2, and 3,
respectively. The rotation treatment 4 provided
the best protection of wrapper leaf damage. The
highest marketable yield was in treatments 2, 6, 3,
7, 4, and 5, respectively. It was interesting to note
that there was significant thrips control on
cabbage foliage on April 20 (with Warrior
providing the best control) and a marginally
significant level of control on April 26 but not
over the whole season. There was also a
significant level of control of the foliar aphids in
this test based on the season mean but not on
individual dates.
It is clear from the results of this test that
chemical rotations are a viable option for the
management of diamondback moth in cabbage.
All rotations, treatments 2, treatment 2 modified
with a BAS combination (treatment 4), and the
alternate rotation in treatment 7 provided the
highest levels of diamondback control in this test.
It is also clear that the use of single insecticide
chemistries such as the pyrethroid insecticide,
Warrior, can lead to problems when apparently
resistant diamondback moths are present. In this
test, the use of Warrior alone resulted in as much
damage as an untreated control. The combination
of Warrior with BAS320 did, however, overcome
Materials and Methods
Cabbage, var. Bravo, was transplanted
into 2 rows per 6-ft beds on March 14, 2006 and
maintained with standard cultural practices at the
Lang Farm, Georgia Coastal Plain Experiment
Station at Tifton. A total of 500 lbs of 10-10-10
was applied to Tift pebbly clay loam field plots
initially followed by 250 lbs of 10-10-10 at first
side dressing and 200 lbs of ammonia nitrate at
second side dressing. Irrigation was applied at
about one half inch weekly with an overhead
sprinkler system. Scouting was initiated on March
21 and continued weekly until harvest on May 30.
Nine applications of insecticide were made from
March 30 to May 26, and 2 samples of 6 plants
were scouted per plot approximately 96 h after
weekly applications. Twenty heads of cabbage
were harvested from 20 ft of row on May 30, and
heads were categorized as marketable or
unmarketable, and the average weight was
measured. Damage ratings for worm damage to
wrapper leaves and heads were reported. Data was
analyzed using GLM and LSD tests for separation
of means (SAS Institute 1985).
93
this lack of control. Combining BAS320 with
other insecticides in a rotation provided very high
levels of control of diamondback moth.
aphid
3/31/06
seasonal
mean
aphid
thrips
4/06/06
thrips
4/20/06
thrips
4/26/06
seasonal
mean
thrips
1. Warrior T .015 lb ai/a
+ Penetrator .25% u/v
0.50a
0.09b
3.88a
14.75d
9.50a
7.33a
2. 1st ROTATION - 2 Weeks each
Proclaim 5 WDG 0.012 lb ai/a
Avaunt 30 WDG .065 lb ai/a
Spintor 2SC .156 lb ai/a
0.58a
0.17ab
6.38a
14.63d
4.88bc
7.74a
3. BAS320 280g ai/ha
+ Warrior T .015 lb ai/a
+ Penetrator .25% v/v
0.29a
0.15b
6.88a
16.25bcd
9.38ab
8.79a
4. BAS320 280g ai/ha
+ Proclaim, Avaunt, Spintor see
1st rotation
+ Penetrator Rotation .25% v/v
0.46a
0.14b
5.63a
22.13abc
4.25c
8.21a
5. Xentari 1 lb prod/a
0.71a
0.17ab
8.25a
24.88a
5.63abc
9.59a
6. Xentari 1 lb prod/a
Tesoro 4.8 oz prod/a
0.63a
0.23a
7.38a
16.13bcd
8.88ab
7.88a
7. 2nd ROTATION - 2 Weeks each
Xentari 1 lb prod/a
Tesoro 4.8 oz prod/a
0.38a
0.16ab
9.00a
15.38cd
6.00abc
7.76a
Treatment - rate per acre
8. Untreated Check
0.75a
0.23b
9.75a
22.88ab
9.75a
9.63a
* Means within columns followed by the same letter are not significantly different (LSD, P<0.05) except
for thrips on 4/26/06 (P<0.1).
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dbm
4/26/06
dbm
4/20/06
dbm
5/04/06
dbm
5/18/06
dbm
5/24/06
cl
5/04/06
cl
5/11/06
icwsm
4/26/06
1. Warrior T .015 lb ai/a
+ Penetrator .25% u/v
4.63a
3.25a
2.75ab
2.17a
3.00a
0.25ab
0.00b
0.00b
2. 1st ROTATION - 2 Weeks each
Proclaim 5 WDG 0.012 lb ai/a
Avaunt 30 WDG .065 lb ai/a
Spintor 2SC .156 lb ai/a
0.38b
0.50c
1.25bc
0.13b
0.13b
0.00b
0.00b
0.25ab
3. BAS320 280g ai/ha
+ Warrior T .015 lb ai/a
+ Penetrator .25% v/v
1.13b
0.00c
0.63c
0.00b
0.88b
0.00b
0.00b
0.00b
4. BAS320 280g ai/ha
+ Proclaim, Avaunt, Spintor see
1st rotation
+ Penetrator Rotation .25% v/v
0.00b
0.00c
0.29c
0.75b
0.56b
0.00b
0.00b
0.00b
5. Xentari 1 lb prod/a
1.25b
1.13cb
0.33c
0.50b
0.58b
0.00b
0.00b
0.00b
6. Xentari 1 lb prod/a
Tesoro 4.8 oz prod/a
0.13b
0.00c
0.25c
0.00b
0.00b
0.00b
0.38a
0.00b
7. 2nd ROTATION - 2 Weeks each
Xentari 1 lb prod/a
Tesoro 4.8 oz prod/a
0.63b
0.75c
1.50bc
0.38b
0.00b
0.00b
0.00b
0.00b
8. Untreated Check
5.63a
2.13ab
3.25a
1.17ab
2.60a
* Means within columns followed by the same letter are not significantly different (LSD, P<0.05).
0.38a
0.13ab
0.38a
Treatment - rate per acre
95
seasonal
mean
dbm
seasonal
mean
small
icw
seasonal
mean
Lepidopt
era
mean
wrapper
damage
mean
head
damage
mean
wrapper
damage
marketable
mean head
damage
marketable
total
marketabl
e weight
(lb.)
1. Warrior T .015 lb ai/a
+ Penetrator .25% u/v
1.65a
0.49a
2.34a
1.45a
0.68b
0.98a
0.68b
58.38bc
2. 1st ROTATION - 2 Weeks each
Proclaim 5 WDG 0.012 lb ai/a
Avaunt 30 WDG .065 lb ai/a
Spintor 2SC .156 lb ai/a
0.24b
0.11b
0.42b
0.80b
0.22bcd
0.64bc
0.13cd
106.20ab
3. BAS320 280g ai/ha
+ Warrior T .015 lb ai/a
+ Penetrator .25% v/v
0.26b
0.09b
0.40b
0.85b
0.15bcd
0.82ab
0.16cd
89.63ab
4. BAS320 280g ai/ha
+ Proclaim, Avaunt, Spintor see
1st rotation
+ Penetrator Rotation .25% v/v
0.16b
0.06b
0.26b
0.29c
0.12cd
0.29d
0.12cd
84.14ab
5. Xentari 1 lb prod/a
0.41b
0.18b
0.63b
0.88b
0.65bc
0.81ab
0.61bc
82.10ab
6. Xentari 1 lb prod/a
Tesoro 4.8 oz prod/a
0.04b
0.00b
0.10b
0.63bc
0.08d
0.58c
0.08d
110.95a
7. 2nd ROTATION - 2 Weeks each
Xentari 1 lb prod/a
Tesoro 4.8 oz prod/a
0.36b
0.06b
0.46b
0.63bc
0.08d
0.61c
0.08d
85.53ab
8. Untreated Check
1.51a
0.46a
2.33a
1.78a
1.57a
* Means within columns followed by the same letter are not significantly different (LSD, P<0.05).
1.00a
1.43a
31.60c
Treatment - rate per acre
96