(E89) TOMATO: Lycopersicon esculentum Miller, ‘Solar Set’ CONTROL OF BEET ARMYWORM IN TOMATO, 2004 Dakshina R. Seal Tropical Research and Education Center Homestead, FL 33031 Phone: (305) 246-7001 Fax: (305) 246-7003 E-mail:
[email protected] Beet armyworm: Spodoptera exigua (Hübner) ‘Solar Set’ tomato seedlings were transplanted in a Rockdale soil on 2 Apr 2004. A RCB design was employed to provide four replicates each for nine treatments comprising a plot size of 2 rows wide and 30 ft long. All treatments were applied on four dates–10, 17, 24 and 31 May 2004 using a backpack sprayer with two nozzles per row delivering 70 - 100 gpa at 30 psi. Treatments were evaluated 24 h after each application by thoroughly checking randomly selected five plants per treatment plot for beet armyworm larvae. Data were subjected to ANOVA and means were separated using DMRT (P ≤ 0.05). Beet armyworm population abundance was low to medium during this study. All insecticide treatments significantly reduced beet armyworm small larvae on tomato. Mean numbers of beet armyworm medium size larvae were significantly fewer in Baythoid 2 and Baythroid XL treated plants followed by Mustang and Sevin when compared with the nontreated control. However, Sevin did not differ from nontreated control. All insecticide treatments also significantly reduced beet armyworm large size larvae. When all development stages were considered together, insecticide treatments significantly reduced beet armyworm population in tomato when compared with the nontreated control. Mean numbers of larvae, (small + medium + large) when combined together, per plant treated with Sevin did not differ from nontreated control. Table 1. Treatment/ formulation Baythroid 2EC Baythroid XL 1EC Sevin 4SC Mustang 1.5EW Untreated check
Mean numbers of small larvae Rate amt product/acre 11 May 18 May 25 May 1 Jun Mean 2.4 fl oz 2.8 fl oz 2.0 pt 4.0 fl oz --
0.60b 0.70b 0.65b 0.70b 2.30a
0.25b 0.45b 0.70b 0.15b 2.05a
0.20b 0.20b 0.50b 0.20b 1.60a
0.05b 0.30b 0.20b 0.15b 0.85a
Means within a column followed by the same letter do not differ statistically (P > 0.05, DMRT).
0.27b 0.41b 0.51b 0.30b 1.70a
Table 2. Treatment/ formulation Baythroid 2EC Baythroid XL 1EC Sevin 4SC Mustang 1.5EW Untreated check
Mean numbers of medium larvae Rate amt product/acre 11 May 18 May 25 May 1 Jun Mean 2.4 fl oz 2.8 fl oz 2.0 pt 4.0 fl oz --
0.50a 0.40a 0.50a 0.30a 0.55a
0.35b 0.35b 0.50b 0.60b 1.10a
0.15a 0.10b 0.27b 0.15a 0.05b 0.24b 0.35a 0.25ab 0.40ab 0.10a 0.10b 0.27b 0.40a 0.45a 0.62a
Means within a column followed by the same letter do not differ statistically (P > 0.05, DMRT).
Table 3. Treatment/ formulation Baythroid 2EC Baythroid XL 1EC Sevin 4SC Mustang 1.5EW Untreated check
Mean numbers of large larvae Rate amt product/acre 11 May 18 May 25 May 1 Jun Mean 2.4 fl oz 2.8 fl oz 2.0 pt 4.0 fl oz --
0.20ab 0.35ab 0.10b 0.05a 0.17b 0.00b 0.45ab 0.10b 0.15a 0.17b 0.50a 0.55ab 0.20b 0.05a 0.32ab 0.40ab 0.25b 0.05b 0.10a 0.20b 0.10b 0.80a 0.55a 0.30a 0.44a
Means within a column followed by the same letter do not differ statistically (P > 0.05, DMRT).
Table 4. Treatment/ formulation Baythroid 2EC Baythroid XL 1EC Sevin 4SC Mustang 1.5EW Untreated check
Mean numbers of BAW (all larvae together) Rate amt product/acre 11 May 18 May 25 May 1 Jun Mean 2.4 fl oz 2.8 fl oz 2.0 pt 4.0 fl oz --
1.30b 1.10b 1.65ab 1.40b 2.95a
0.95c 1.25bc 1.75b 1.00bc 3.95a
0.45bc 0.45bc 1.05b 0.35c 2.55a
0.20b 0.50b 0.50b 0.35b 1.60a
0.72c 0.82c 1.24ab 0.77c 2.76a
Means within a column followed by the same letter do not differ statistically (P > 0.05, DMRT).
