Arthropod Management Tests 2014, Vol. 39
doi: 10.4182/amt.2014.E75
(E75) TOMATO: Solanum lycopersicum L., ‘Phoenix’ INSECTICIDAL CONTROL OF SOUTHERN ARMYWORM ON STAKED TOMATO IN SW FLORIDA, 2012 Philip A. Stansly University of Florida/ IFAS Southwest Florida Res. and Ed. Center 2686 State Road 29 North Immokalee, FL 34142-9515 Phone: (239) 658-3427 Fax: (239) 658-3469 Email:
[email protected] Barry C. Kostyk Email:
[email protected] Southern armyworm (SAW): Spodoptera eridania (Stoll) Armyworm: Spodoptera albula (Walker) Southern armyworm is the major lepidopteran pest of tomato in the southern tier of Florida whereas S. albula is usually a minor player early in the crop cycle. Uncontrolled populations of SAW cause severe defoliation and fruit damage and result in serious yield losses. This trial was conducted at the University of Florida-IFAS Southwest Florida Research and Education Center in Immokalee. Greenhouse-raised seedlings were planted 5 Sep at 18 inch spacing on two sets of three raised beds on 6 ft centers, each covered with white-faced polyethylene film. An RCB design was used with 4 replications and 12 treatments. The center row in each three bed section was left untreated and acted as a refuge for pests. Each plot contained 18 plants with 3 plants left between plots as an untreated buffer. A 10-2-10 granular fertilizer at a rate of 75 lb N/ac was applied preplant and soil incorporated, accounting for 33% of the expected seasonal application of N. The rest was fertigated daily as a 7- 2- 7 NPK liquid through drip tape with 8 inch emitter spacing. Kocide (2lbs/acre), Manzate 75 DF (1.5 lbs/acre), and Actigard (0.5 oz acre) were applied as needed for disease control, principally bacterial spot. All plants were drenched on 10 Sep with a soil application of Admire Pro at 8.5 oz per acre a 120 ml per plant using an EZDose® applicator at 45 PSI and later sprayed with JMS Stylet Oil (0.50%), Fulfill (2.75 oz) and Courier (13.6 oz) on 8 and 25 Oct, all to reduce whitefly populations and decrease the spread of TYLCV. Foliar insecticide treatments directed at SAW were applied using a high clearance sprayer with two vertical booms operating at 180 psi. Each drop boom was fitted with horizontally directed ATR 80 ® hollow cone nozzles delivering 10 gpa. As plants developed, additional nozzles were added to ensure coverage of the entire plant canopy (Table 1). Eight plants per plot were inspected weekly from 2 Oct thru 20 Nov, and the number of larvae present was counted. Defoliation was rated as: 0 = no damage; 1=67% damaged. Seven plants from each plot were harvested on 29 Nov. Fruit size was graded as XL, large, and medium following USDA criteria. Fruit were also culled into two categories, SAW damage and other causes such as shoulder cracking, zippering etc. Data were analyzed using ANOVA and means separated by LSD test contingent on a significant treatment F value (P>0.05). From 7 Oct through 23 Oct, both Spodoptera species were observed at an approximately1:1 ratio. After 29 Oct only a few specimens of Spodoptera albula were found, and the population was over 95% SAW. Significant differences from the untreated were not observed prior to 23 Oct or on 13 Nov. Only treatments of Xentari, Belt, and rotations of Coragen/Avaunt or MBI206 @ 2 gal/ac/Radiant resulted in significantly fewer larvae and damage compared to the untreated control on all reported dates (Table 2). The remaining treatments showed significant levels of control on some dates but were not consistent in reducing the number of larvae observed or the damage when compared to the untreated check. Only the Coragen/Avaunt and Belt treatments provided significantly higher numbers and weight of marketable fruit when compared to the untreated check, although not significantly different from Xentari or the MBI206/Radiant and Grandevo/Radiant rotations. Significantly fewer culls due to worm damage were seen compared to the untreated check with treatments Coragen/Avaunt, Belt, Xentari and MBI206 @ 2 gal/ac + Radiant rotation although not significantly different from MBI206 at either rate with only Induce. No phytotoxicity was observed. This research was supported by industry gifts of pesticide and research funding. 1
Arthropod Management Tests 2014, Vol. 39
doi: 10.4182/amt.2014.E75
Table 1 Date Applied Rateamt 4-Oct 11-Oct 18-Oct 25-Oct 1-Nov 8-Nov 15-Nov 21-Nov Treatment product/acre 40 gpa 60 gpa 60 gpa 60 gpa 60 gpa 60 gpa 60 gpa 60 gpa Untreated Coragen Avaunt Xentari Belt Grandevo Induce Grandevo Induce MBI 206 Induce MBI 206 Induce Grandevo MBI 206 Induce Grandevo MBI2 06 Induce Grandevo Radiant Induce MBI 206 Radiant Induce
5.0 oz 3.5 oz 1.0 lb 1.5 oz 1 lb 0.25% 2 lb 0.25% 1 gal 0.25% 2 gal 0.25% 1 lb 1 gal 0.25% 2 lb 2 gal 0.25% 2 lbs 6.0 oz 0.25% 2 gal 6.0 oz 0.25%
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 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 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
x x
x
x x x
x x x
x
x
x x
x x
2
Arthropod Management Tests 2014, Vol. 39
doi: 10.4182/amt.2014.E75
Table 2 Total of 7 plants Number of Larvae per plant Treatment
Rate amt product/acre
Untreated Coragen Avaunt Xentari Belt Grandevo Induce Grandevo Induce MBI 206 Induce MBI 206 Induce Grandevo MBI 206 Induce Grandevo MBI 206 Induce Grandevo Radiant Induce MBI 206 Radiant Induce
5.0 oz 3.5 oz 1.0 lb 1.5 oz 1 lb 0.25% 2lb 0.25% 1 gal 0.25% 2 gal 0.25% 1 lb 1 gal 0.25% 2 lb 2 gal 0.25% 2 lbs 6.0 oz 0.25% 2 gal 6.0 oz 0.25%
23-Oct
29-Oct
7-Nov 20-Nov
1.91ab 0.00c
3.93a 0.00c
2.31a 0.00b
0.00c 0.00c 1.38abc
0.00c 0.00c 2.25ab
0.53bc
Damage Rating 29-Oct
7-Nov
1.69a 0.00e
1.06a 0.00d
0.82a 0.00d
0.00b 0.00b 0.00b 0.00b 1.00ab 0.22ab
0.06e 0.09e 1.63a
0.09d 0.15d 0.13d 0.06d 0.91ab 0.63ab
0.03c
2.25a
0.34ab
0.50cde 0.13d
0.09c
0.00c
0.53b
0.00b
0.63bcd 0.32cd 0.34bcd 0.16de
0.13ef
38.50bc 16.85bc
8.25bc
3.10bc
0.06c
0.06c
0.09b
0.00b
0.09e
0.22d
0.09d
0.06e
0.13ef
36.75bc 16.20bc
7.50bc
3.08bc
1.03abc
0.94bc
0.94ab 0.03b
1.78a
1.09a
0.69ab
0.91a
1.00a
25.50c
12.00ab
5.18ab
2.25a
0.28bc
0.97ab 0.03b
1.03b
0.59bc 0.53abc 0.63abc 0.88ab
32.00bc 10.63c
11.00ab
4.65b
0.82abc
1.18bc
0.09b
0.00b
0.97bc
0.84ab 0.31cd
0.22de
0.38cde
48.00ab 21.53ab
7.25bc
3.30bc
0.00c
0.00c
0.03c
0.00c
0.34de
0.09d
0.13de
0.19def
49.25ab 21.53ab
2.50c
1.10c
0.63ab
0.13d
0.72ab 0.00e
20-Nov 1.13a 0.00f
No. 33.5bc 57.25a
Wt(lbs)
Lepidopteron Damage
23-Oct
0.59a 0.00b
13-Nov
Marketable
16.7bc 26.05a
0.06e 0.00f 0.06e 0.00f 0.50bcd 0.63bc
45.75ab 21.38ab 60.25a 26.30a 27.25c 12.53c
0.35cde 0.53bcd
27.50c
Means followed by same letter are not statistically different (LSD>0.05).
3
12.80c
15.10bc
No.
Wt(lbs)
12.50ab 1.00c
5.25ab 0.50c
0.25c 0.75c 6.75bc
0.20c 0.28c 3.03bc
18.25a
8.15a
