Arthropod Management Tests 2009, Vol. 34
doi: 10.4182/amt.2009.J1
(J1)
EFFICACY AND RESIDUAL EFFECT OF TYCOON G, DEMAND G AND DELTAGARD G AGAINST
SELECTED NUISANCE ANTS, 2008
Timothy J. Husen
Department of Entomology
202 Entomology Hall, East Campus
University of Nebraska – Lincoln
Lincoln, NE 68583-0816
Phone: (402) 472-2076
Fax: (402) 472-4687
E-mail: [email protected]
Neil A. Spomer
E-mail: [email protected]
Ralph Narain
E-mail: [email protected]
Shripat T. Kamble
E-mail: [email protected]
Dina Richman
E-mail: [email protected]
Brian Mount
E-mail: [email protected]
Bigheaded ant (BHA): Pheidole megacephala (F.)
False honey ant (FHA): Prenolepis imparis (Say)
Odorous house ant (DHA): Tapinoma sessile (Say)
Pavement ant (PA): Tetramorium caespitum (L.)
Thief or grease ant (TA): Solenopsis molesta (Say)
The objective of this study was to evaluate residual efficacy of Tycoon® G (bifenthrin, 0.2% plus zeta-cypermethrin,
0.05%) at multiple label rates against nuisance ants under field settings, and to compare its efficacy against Demand® G
(lamda-cyhalothrin, 0.045%) and DeltaGard® G (deltamethrin, 0.1%). The experimental sites used for this study were the
Agronomy and Horticulture Greenhouses, University of Nebraska, Lincoln, NE. Pretreatment ant populations (BHA, FHA,
ODHA, PA, and TA) were assessed by placing ant traps in plots (each, 5 × 5 ft. with 3 ft. buffer between plots) along the
perimeter of the greenhouse foundation. Ant traps were made of cylindrical, plastic culture tubes (17 × 100 mm) (VWR,
Chicago, IL) with entrance holes on each side at the bottom end of the tube. Peanut butter wrapped in paper was used as
bait within each ant trap. Of the 91 experimental plots initially monitored, 30 plots with highest foraging ant populations
were selected for this study. The ground cover of the plots was variable with plots having all rock, rock/concrete,
rock/grass, or all grass. These ground covers simulate the variable landscapes around homes. Five plots were randomly
assigned to one of six treatments. The experimental design was a completely randomized design (CRD) with five replicates
per treatment (Table 1). Pretreatment foraging nuisance ant populations were used as baseline data for calculating the
percent reduction resulting from insecticide treatments. The insecticides and application methods used in this study are
specified in Table 1. All insecticides were applied according to protocols. Insecticide granules, in all treatments, were preweighed and stored individually in Zip-Loc® bags prior to experimental use. The Tycoon G treatments were applied to the 5
ft2 plot using a spice shaker (Hy-Vee, West Des Moines, IA). The small holes of the spice shaker allowed for a slow and
even distribution of granules. Demand G and DeltaGard G were all applied to the 5 ft2 plots using a glass cheese shaker
(Libbey Inc., East Cambridge, MA). The holes of the glass cheese shaker were considerably larger than those of the spice
shaker and allowed for slow and even distribution of the pellet sized granules. After insecticide applications, all plots were
sprinkled with 1.5 to 2 gal water depending upon ground cover of respective plots. Ant populations were monitored at 1, 14
(2w), 28 (≈1m), 56 (≈2m), 84 (≈3m), and 112 (≈4m) days after each treatment (DAT). At each monitoring interval with the
exception of 4m, traps were placed in each plot along the greenhouse foundation from 5:00 to 7:00 P.M. and then were
collected the next morning from 8:00 to 10:00 A.M. Due to cold weather at the 4m interval, traps were placed in each plot
1
Arthropod Management Tests 2009, Vol. 34
doi: 10.4182/amt.2009.J1
from 9:00 to 10:00 A.M. and were collected from 5:30 to 6:30 P.M. Samples were stored individually and nuisance ants
were identified and counted using a Baush & Lomb dissecting scope. Pretreatment nuisance ant population counts were
collected one week prior to insecticide applications. Percent reduction in foraging ant populations were calculated using pre
and post treatment nuisance ant populations with the equation [(T0 – T1) / T0] * 100 = % Reduction of nuisance ant
population where, T0 = Pretreatment nuisance ant population and T1 = Post treatment nuisance ant population. Mean %
reduction in ant population for each treatment at each monitoring interval was analyzed by ANOVA with statistical
significance tested by student’s t-test (P < 0.05).
The mean % reductions in nuisance ant population for each treatment are listed in Table 2. At the 1 DAT monitoring
interval, the Tycoon G (4.6 lb/1,000 ft2) treatment had the highest percent reduction of nuisance ant population (Table 2).
The Tycoon G (4.6 lb/1,000 ft2) treatment provided significantly greater control than the Demand G (p < 0.0008), the
DeltaGard G (p < 0.0416), and the control (p < 0.0002) treatments. Both of the Tycoon G treatments (1.15 and 2.3 lb/1000
ft2) provided significantly greater reduction in ant populations than the control treatment (p < 0.0339 and p < 0.0039,
respectively). The Tycoon G at 2.3 lb/1000 ft2 had significantly less ant populations than the Demand® G treatment (p <
0.0125). At the 2 week interval, the Tycoon G (4.6 lb/1000 ft2) treatment showed the greatest percent reduction in foraging
ants (Table 2). Significant differences were observed between the Tycoon G (4.6 lb/1000 ft2) treatment and the Demand G
(p < 0.0016), DeltaGard G (p < 0.0045), and control treatments (p < 0.0014). Tycoon G (2.3 lb/1000 ft2) also provided
significantly greater control than the Demand G (p < 0.0188), DeltaGard G (p < 0.042), and control treatments (p < 0.0167).
At 1 month after treatment, Tycoon G (4.6 lb/1000 ft2) remained the most efficacious at controlling nuisance ants (Table 2).
The Tycoon G (4.6 lb/1000 ft2) treatment was superior to the Tycoon G (1.15 lb/1000 ft2) (p < 0.0155), Demand G (p <
0.0069), DeltaGard G (p < 0.0072), and control treatment (p < 0.0013). The Tycoon G (2.3 lb/1000 ft2) treatment also
significantly outperformed the control treatment (p < 0.0155). At 2 months after treatment, the highest application rate of
the Tycoon G (4.6 lb/1000 ft2) provided the best residual efficacy (Table 2). The residual efficacy of the Tycoon G (4.6
lb/1000 ft2) treatment was significantly greater than that of Demand G (p < 0.002), DeltaGard G (p < 0.009), Tycoon G (2.3
lb/1000 ft2) (p < 0.0222), and control treatments (p < 0.0023). A similar trend was seen at 3 months after treatment (Table
2). Tycoon G (4.6 lb/1000 ft2) treatments were emphatically better at reducing foraging ant populations than both of the
lower application rates of the same formulation, Demand G, and control treatment (all p < 0.0239). At 4 months after
treatment, the efficacy of Tycoon G (4.6 lb/1000 ft2) was significantly greater than all treatments except DeltaGard G (all p
≤ 0.0186).
Table 1
Insecticide
a
Tycoon G
Tycoon G
Tycoon G
b
Demand G
c
DeltaGard G
Untreated Control
Application Rate
2
Application Method
(lb/1000 ft )
1.15
2.3
4.6
2.0
2.0
na
Shaker spreader/Water
Shaker spreader/Water
Shaker spreader/Water
Shaker spreader/Water
Shaker spreader/Water
na
a
Replications
5
5
5
5
5
5
b
Tycoon G (0.2% bifenthrin, 0.05% zeta-cypermethrin); Demand G (0.045%
c
lambda-cyhalothrin); DeltaGard G (0.10% deltamethrin).
Table 2
1
Mean % Reduction of Nuisance Ant Populations (Post-trt.)
Treatment
a
Tycoon G (1.15 lb)
Tycoon G (2.3 lb)
Tycoon G (4.6 lb)
b
Demand G (2 lb)
c
DeltaGard G (2 lb)
Untreated Control
1 Day
2 Week
4 Week
2 Month
3 Month
4 Month
57.4abc
77.3ab
99.4a
13.6cd
47.5bcd
3.4 d
52.1c
76.1ab
97.0a
16.2c
24.4c
15.1c
35.8bc
74.9ab
95.9a
26.9bc
27.2bc
13.2c
55.9abc
40.0bc
98.3a
19.1c
46.7bc
20.0c
36.6bc
33.1c
97.6a
20.0c
62.5abc
40.0bc
20.0c
40.0bc
100.0a
40.0bc
59.2abc
40.0bc
1
Means followed by different letters in columns are significantly different (p ≤ 0.05).
b
Tycoon G (0.2% bifenthrin, 0.05% zeta-cypermethrin); Demand
c
G (0.045% lambda-cyhalothrin); DeltaGard G (0.10% deltamethrin).
a
2