Arthropod Management Tests 2012, Vol. 37
doi: 10.4182/amt.2012.C22
(C22)
STRAWBERRY: Fragaria × ananassa Duchesne, ‘Strawberry Festival’
EFFICACY OF MITICIDES FOR CONTROL OF TWOSPOTTED SPIDER MITE IN STRAWBERRY, 2010-11
Curtis A. Nagle
University of Florida-IFAS
Gulf Coast Research and Education Center
14625 CR 672
Wimauma, FL 33598
Phone: (813) 633-4122
Fax: (813) 634-0001
Email: [email protected]
James F. Price
Email: [email protected]
Twospotted spider mite (TSM): Tetranychus urticae Koch
The efficacies of five traditional chemistry-derived and two biologically-derived active ingredients were evaluated for TSM control at
the Gulf Coast Research and Education Center (GCREC), Wimauma, Fla. in the winter of 2010-11. ‘Strawberry Festival’ transplants
were set in the field on 5 Oct 2010 in plastic mulched beds, 13 inches high and 27 inches across the top, and with 4-ft bed spacing.
Overhead irrigation was applied for 10 days after setting to aid in establishment of the transplants. Trickle irrigation was used for the
remainder of the experiment. Each 12.5-ft plot consisted of 20 plants in two ten-plant rows per bed. Plots were infested from a
laboratory colony in four sessions from 29 Nov thru 15 Dec, with 10 to 20 motile TSM, per plant. Each session accomplished the
infestation of one block of the experiment. The experiment consisted of 17 treatments of various rates and schedules of application of
miticides, some combined with an adjuvant, and a non-treated check (Table 1). Treatments were replicated four times in a RCB
design. Savey and Acramite treatments were applied before TSM densities reached threshold levels (6 Jan); the remainder of the
treatment programs began 2 wks later (Table 1). Treatments were applied using a hand-held sprayer with a spray wand outfitted with
a nozzle containing a 45-degree core and a number four disc. The sprayer was pressurized by CO2, to 40 psi, and calibrated to deliver
100 gpa. Pre-treatment samples were taken on 3 Jan and sampling continued weekly through 2 wks after the last application of
treatments (8 Mar). Samples consisted of ten randomly selected leaflets per plot and were collected from the middle one-third stratum
of the plants. Samples were transported to the laboratory where motile and egg TSM were brushed from the leaflets onto rotating
sticky discs and counted on 1/10 of the disc surface to estimate average numbers per leaflet. Distinctions could not be made between
viable and non-viable eggs, thus total eggs were recorded. Data were transformed log10(x+1) prior to ANOVA and means were
separated by Fisher’s Protected LSD test (P≤0.05). Means were reported in the original scale.
Average motile TSM density among all plots on 3 Jan was 4.3 per leaflet. Densities remained near that level until 18 Jan, when
average motile mite density among all still untreated plots was 9.6 per leaflet. Eleven days after the last of the initial applications had
been made (31 Jan.) lowest densities of mites occurred in plots treated with Agri-Mek, Acramite plus Induce, BAS92100I (excluding
BAS92100I plus Cohere), Oberon plus Induce, or Portal (Table 2). Densities among plots of all other treatments were not
significantly different from those in the non-treated plots. On 14 and 28 Feb lowest densities of mites occurred in plots treated with
Agri-Mek, Oberon plus Induce, or any program of BAS92100I, excluding BAS92100I plus Cohere, and BAS92100I applied twice at
6.85 fl. oz., which possessed least densities only on 28 Feb. MBI-203, applied at 3 gal., plus Induce provided an intermediate level of
control during the period from 7 to 28 Feb (Table 2). On 31 Jan least TSM egg densities occurred in plots treated with Agri-Mek,
Acramite plus Induce, BAS92100I (excluding BAS92100I applied at the lowest rate or when combined with Cohere), Oberon plus
Induce, or Portal (Table 3). Least egg densities consistently occurred in all samples taken from 31 Jan through 28 Feb among plots
treated with Agri-Mek, BAS92100I twice at 13.7 fl. oz. or four times at 6.85 fl. oz., or Oberon plus Induce. No phytotoxicity was
observed. This research was supported by industry gift(s) of pesticides and/or research funding.
1
Arthropod Management Tests 2012, Vol. 37
doi: 10.4182/amt.2012.C22
TABLE 1.
Date of treatment application
Treatment/
a
Formulation
Rate
amt/acre
Non-treated
Agri-Mek 0.15EC
b
Acramite 50WS + Induce
BAS92100I SC (twice)
BAS92100I SC (twice)
BAS92100I SC (four times)
BAS92100I SC (four times)
BAS92100I SC (once)
c
BAS92100I SC + Cohere
Cohere
NAI-2399 5% EW
b
Oberon 2SC + Induce
Portal 5% EC
Savey 50DF
b
MBI-203 + Induce
b
MBI-203 + Induce
b
MBI-206 + Induce
b
MBI-206 + Induce
-16 fl. oz.
1 lb.
6.85 fl. oz.
13.7 fl. oz.
3.43 fl. oz.
6.85 fl. oz.
13.7 fl. oz.
6.85 fl. oz.
16.0 fl. oz.
32 fl. oz.
12 fl. oz.
32 fl. oz.
6 oz.
1 gal.
3 gal.
1 gal.
3 gal.
6 Jan
20 Jan
27 Jan
X
X
2 Feb 10 Feb
X
17 Feb
23 Feb
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
a
A ‘+’ sign indicates the products were combined.
®
Induce , non-ionic surfactant, applied at 32 fl. oz./acre.
c
®
Cohere , non-ionic spreader-sticker adjuvant, applied at 16 fl. oz./acre.
b
2
X
X
X
X
Arthropod Management Tests 2012, Vol. 37
doi: 10.4182/amt.2012.C22
TABLE 2.
No. motile TSM/leaflet
Treatment/
a
Formulation
Non-treated
Agri-Mek 0.15EC
b
Acramite 50WS + Induce
BAS92100I SC (twice)
BAS92100I SC (twice)
BAS92100I SC (four times)
BAS92100I SC (four times)
BAS92100I SC (once)
c
BAS92100I SC + Cohere
Cohere’
NAI-2399 5% EW
b
Oberon 2SC + Induce
Portal 5% EC
Savey 50DF
b
MBI-203 + Induce
b
MBI-203 + Induce
b
MBI-206 + Induce
b
MBI-206 + Induce
F17,51
P-value
Rate
amt/acre
-16 fl. oz.
1 lb.
6.85 fl. oz.
13.7 fl. oz.
3.43 fl. oz.
6.85 fl. oz.
13.7 fl. oz.
6.85 fl. oz.
16.0 fl. oz.
32 fl. oz.
12 fl. oz.
32 fl. oz.
6 oz.
1 gal.
3 gal.
1 gal.
3 gal.
3 Jan
11 Jan
18 Jan
24 Jan
31 Jan
7 Feb
14 Feb
22 Feb
28 Feb
8 Mar
8.8a
8.5a
1.5a
1.8a
9.5a
7.5a
5.8a
2.8a
2.3a
2.8a
4.0a
2.8a
4.5a
2.0a
4.3a
2.8a
5.0a
1.5a
2.0a
4.5a
1.8a
3.3a
5.5a
6.8a
4.5a
3.3a
3.8a
5.5a
3.8a
2.3a
3.8a
1.8a
-
7.3a
6.3a
3.3a
3.3a
32.3a
28.8a
2.3a
5.8a
11.0a
7.0a
15.3a
2.0a
6.5a
2.8a
9.5a
4.5a
6.8a
5.0a
4.8a
5.3a
1.8a
1.3a
1.3a
3.0a
2.3a
3.8a
8.3a
5.5a
3.5a
2.3a
2.8a
6.0a
7.8a
5.3a
3.5a
2.5a
14.3a
0.5e
3.0c-e
1.3de
1.8c-e
5.5b-e
0.8e
1.3e
16.3a-c
14.3ab
10.5ab
0.5e
2.0c-e
13.8ab
10.3a-d
16.0ab
9.0ab
12.8a
47.5a
0.5h
23.0c-f
1.8f-h
1.0gh
2.3e-h
0.3h
1.0gh
11.0d-g
34.3ab
8.3e-h
0.8gh
7.3c-f
23.0ab
18.0a-d
8.8b-e
37.3a
24.3a-c
89.8a
3.0d-f
18.3de
3.0de
1.0ef
3.5ef
0.0f
1.8ef
22.3cd
72.5ab
6.8cd
0.5ef
5.3de
57.5ab
54.5ab
22.5bc
42.5ab
35.5ab
150.5a
6.3fg
17.0fg
4.0fg
0.5h
2.8gh
2.8gh
6.0gh
57.3c-e
121.3ab
21.5d-f
2.5gh
10.0e-g
103.3ab
97.8a-c
38.8b-d
91.0ab
69.3bc
277.5a
6.8g-i
36.8e-h
5.8hi
7.5f-i
5.5hi
3.8i
9.3hi
78.0e-g
237.8a
54.5c-e
2.8i
34.3d-f
196.0ab
196.3ab
87.5b-d
207.3ab
125.8a-c
319.0a
15.3e-g
118.5cd
51.0de
27.8e
15.5e-g
10.5fg
35.8ef
104.3b-d
270.0a
123.3b-d
6.0g
145.3a-c
285.5a
218.0ab
156.0a-c
277.0a
135.5a-c
1.35
0.2039
0.75 (F13,39)
0.7002
0.94
0.5322
4.44
<0.0001
7.82
<0.0001
11.12
<0.0001
13.26
<0.0001
15.86
<0.0001
13.84
<0.0001
1.34
0.2078
Data were transformed log10(x+1) prior to ANOVA; non-transformed means are reported. Means within a column followed by the same letter are not significantly
different by Fisher’s Protected LSD (P≤0.05).
a
A ‘+’ sign indicates the products were combined.
b
®
Induce , non-ionic surfactant, applied at 32 fl. oz./acre.
c
®
Cohere , non-ionic spreader-sticker adjuvant, applied at 16 fl. oz./acre.
3
Arthropod Management Tests 2012, Vol. 37
doi: 10.4182/amt.2012.C22
TABLE 3.
No. egg TSM/leaflet
Treatment/
a
Formulation
Non-treated
Agri-Mek 0.15EC
b
Acramite 50WS + Induce
BAS92100I SC (twice)
BAS92100I SC (twice)
BAS92100I SC (four times)
BAS92100I SC (four times)
BAS92100I SC (once)
c
BAS92100I SC + Cohere
Cohere
NAI-2399 5% EW
b
Oberon 2SC + Induce
Portal 5% EC
Savey 50DF
b
MBI-203 + Induce
b
MBI-203 + Induce
b
MBI-206 + Induce
b
MBI-206 + Induce
F17,51
P-value
Rate
amt/acre
-16 fl. oz.
1 lb.
6.85 fl. oz.
13.7 fl. oz.
3.43 fl. oz.
6.85 fl. oz.
13.7 fl. oz.
6.85 fl. oz.
16.0 fl. oz.
32 fl. oz.
12 fl. oz.
32 fl. oz.
6 oz.
1 gal.
3 gal.
1 gal.
3 gal.
3 Jan
15.5a
6.8a
3.8a
5.8a
6.0a
19.0a
7.0a
8.8a
9.3a
6.8a
11.3a
7.3a
9.3a
2.0a
8.0a
5.0a
12.3a
3.3a
0.95
0.5194
11 Jan
10.0a
17.0a
6.0a
6.5a
12.0a
32.5a
12.8a
8.5a
11.3a
15.5a
12.8a
5.3a
11.8a
8.5a
0.96 (F13,39)
0.5042
18 Jan
24 Jan
31 Jan
7 Feb
14 Feb
22 Feb
28 Feb
8 Mar
27.5ab
26.5ab
6.0d
5.5d
29.8ab
40.0a-c
4.3d
18.8a-d
31.0ab
11.8a-d
35.0a
7.3d
12.3cd
15.0a-d
27.3ab
11.0b-d
20.0ab
8.8b-d
12.3a
12.0ab
0.8c
7.0ab
7.5ab
13.3ab
14.5a
8.3ab
18.3a
16.8a
19.3a
5.0bc
12.5ab
17.0a
20.5a
14.5a
12.0ab
13.5a
25.3a
1.3ef
8.3b-f
1.3ef
4.0c-f
17.3a-c
0.8f
1.0f
15.0b-e
31.5ab
11.0b-d
1.5d-f
1.0f
22.0ab
19.5ab
11.0a-c
12.5ab
21.0ab
122.0a
2.3gh
20.5c-e
4.5d-g
2.5f-h
3.8e-g
0.3h
2.0f-h
31.0d-f
148.3a
24.5cd
2.3f-h
34.5bc
71.5ab
56.3ab
30.0bc
65.5ab
54.3ab
181.5a
6.5hi
3.0i
7.3f-h
5.5g-i
7.3hi
2.0i
2.5i
27.5e-g
114.0ab
17.8ef
2.8hi
20.8de
128.5ab
91.8a-c
35.5c-e
83.3a-c
72.0b-d
587.0a
3.5f-h
28.0ef
5.0f-h
0.8gh
11.0ef
4.8f-h
8.5fg
149.3cd
321.0ab
49.8de
0.8h
28.5d
281.5ab
187.3bc
57.8cd
292.0a-c
158.0cd
559.0a
3.5gh
66.5de
13.3e-g
22.3e-h
9.5f-h
3.5h
17.5ef
132.3cd
525.3a
213.0bc
4.5f-h
97.3cd
393.5ab
304.5ab
238.3a-c
478.0ab
301.3ab
423.0a
41.3e-g
128.3b-f
99.8c-f
85.8d-f
65.5fg
36.0g
99.3e-g
164.5a-e
377.0a
234.3a-d
25.5fg
240.8a-d
533.0a
432.3a
341.5ab
320.5ab
278.0a-c
4.48
<0.0001
13.52
<0.0001
18.40
<0.0001
19.96
<0.0001
19.16
<0.0001
5.13
<0.0001
2.12
0.0201
1.93
0.0363
Data were transformed log10(x+1) prior to ANOVA; non-transformed means are reported. Means within a column followed by the same letter are not significantly
different by Fisher’s Protected LSD (P≤0.05).
a
A ‘+’ sign indicates the products were combined.
b
®
Induce , non-ionic surfactant, applied at 32 fl. oz./acre.
c
®
Cohere , non-ionic spreader-sticker adjuvant, applied at 16 fl. oz./acre.
4