Arthropod Management Tests 2012, Vol. 37
doi: 10.4182/amt.2012.E13
(E13)
CABBAGE: Brassica oleracea L., ‘Early Jersey Wakefield’
EFFICACY OF DRENCH APPLICATIONS OF SCORPION AND VENOM TO CONTROL APHIDS IN LATE SEASON
CABBAGE, 2010
Alana L. Jacobson
Department of Entomology
Box 7613, North Carolina State University
Raleigh, NC 27695-7613
(919) 515-1657 tel
(919) 515-3748 fax
E-mail: [email protected]
George G. Kennedy
E-mail: [email protected]
Green peach aphid (GPA): Myzus persicae (Sulzer)
Turnip aphid (TA): Lipaphis erysimi (Kaltenbach)
The objective of this study was to determine the efficacy of drench applications of Scorpion and Venom to control aphids in late
season cabbage. ‘Early Jersey Wakefield’ cabbage plants were transplanted to the field in Apex, NC on Aug 28, 2010. Plants were
separated within rows by an average of 1.15 feet. Weed control was achieved using Devrinol applied at the rate of 1.5 lb of
formulation per acre as a directed spray on Aug 29, and by cultivation. The planting was divided into single row plots, each 30 ft long
by 3.17 ft wide (Plot = 0.002181 acres). Plots were separated within rows by 10 ft of unplanted row and between rows by 3 unplanted
rows. The treatments (Table 1) were arranged in a RCB design with four replicates. Treatments were applied as transplant drenches in
120 ml of transplant water per plant on Aug 26. Untreated check plants received 120 ml of unadulterated water per plant.
On Sep 4, 11, 19, 24, Oct 10, 16 and 24 (7, 14, 22, 27, 43, 49, 57 and days post-treatment), six randomly selected plants per plot were
thoroughly examined for the presence of apterous aphids. All data were subjected to ANOVA with mean separation by Fisher’s
protected LSD at P≤0.05. Data were transformed to square root (x+0.5) based on inspection of plots of residuals. Data for each
sample date were analyzed separately. All data were subjected to ANOVA with mean separation by Fisher’s protected LSD at
P≤0.05.
Aphid infestations were relatively low throughout this trial. Only GPA and TA were present. No aphids were observed in any plots on
Sep 4 and 11. Because TA numbers were low and variable, and did not differ significantly among treatments, only numbers of GPA
and total numbers of aphids are presented. Numbers of total aphids and numbers of GPA remained significantly lower than in the
untreated control until Oct 16, 49 days post-treatment), at which time numbers in both the Scorpion and Venom treated plots were
comparable to those in the untreated control (Tables 1 & 2). Aphid numbers did not differ between the Scorpion and Venom
treatments on any sample date. No signs of phytotoxicity were observed in any of the treatments. This research was supported by
industry gifts of pesticide and research funding.
Table 1.
Treatment/
Formulation
1. Scorpion SL
2. Venom70
3. Untreated
Rate
Oz form
/acre
10.3
6.0
a
Mean number GPA per 6 plants
Sep 19 Sep 24 Oct 10 Oct 16
Oct 24
1.25b
0.00b
3.50a
38.50a
25.00a
29.75a
2.00b
2.50b
30.00a
3.00b 8.75a
1.78b 13.00a
9.25a 8.0a
a
Means followed by same letter do not differ significantly (P<0.05,
Fisher’s protected LSD).
Data square root transformed prior to analysis. Values are
non-transformed means.
1
Arthropod Management Tests 2012, Vol. 37
doi: 10.4182/amt.2012.E13
Table 2.
Treatment/
Formulation
1. Scorpion SL
2. Venom70
3. Untreated
Rate
Oz form/
acre
10.3
6.0
Meana number GPA per 6 plants
Sep 19 Sep 24 Oct 10 Oct 16
Oct 24
1.25b
0.00b
3.50a
40.25a
29.50a
30.00a
2.00b 3.25b 11.00a
2.50b 5.00b 13.50a
30.00a 14.25a 9.25a
a
Means followed by same letter do not differ significantly (P<0.05,
Fisher’s protected LSD).
Data square root transformed prior to analysis. Values are
non-transformed means.
2