GENETICALLY MODIFIED CORN ON Spodoptera frugiperda
AND Helicoverpa zea CONTROL IN SINALOA, MEXICO
Luis. A. Aguirre-Uribe*, Agustín Hernández-Juárez, Gustavo A. Frías-Treviño, Mariano Flores-Dávila, Ernesto Cerna-Chávez, Jerónimo Landeros-Flores.
Departamento de Parasitología. Universidad Autónoma Agraria Antonio Narro. Calzada Antonio Narro # 1923, Buenavista, Saltillo; Coahuila, México.
*luisaguirreu@yahoo.com.mx
INTRODUCTION
Foliar damage by Spodoptera frugiperda
3.53
2.89
3
2
1
1
1
0
Agrisure
Viptera 3111 a
MATERIALS AND METHODS
Agrisure
Viptera 3111 +
CP a
isoline + CP b
isoline b
Plants with leaf damage by Spodoptera frugiperda
Plants with damage (%)
4
Davis scale
Different corn hybrids have been genetically modified (GM) with the insertion of
genes that express the ∂-endotoxin of Bacillus thuringiensis (Bt) (Bruck et al.
2006), in which the plant expresses the protein with insecticidal activity
primarily against Lepidoptera and some Coleoptera insects (Silva, 2005). In
Mexico, GM corn planting is not authorized for commercial purposes; however,
Bt maize planting was permitted under biosafety conditions to test their pest
control effectiveness. The objective of this research was to evaluate Agrisure
Viptera 3111 and Agrisure 3000 GT corn hybrids expressing B. thuringiensis
toxins on S. frugiperda and H. zea control in Sinaloa, Mexico.
RESULTS
80
70
60
50
40
30
20
10
0
64.4
0
Gallery (cm)
2.5
2.1
2
1.5
1
0.5
0.33
0.45
0
Agrisure
isoline + CP b
isoline b
Viptera 3111 +
CP a
*Treatments with the same are not significantly different (P<0.05)
Ears with damage by Helicoverpa zea
100
93.3
60
40
40
46.7
20
0
Agrisure
Agrisure
Viptera 3111 a Viptera 3111 +
CP a
Agrisure
isoline + CP b
isoline b
Viptera 3111 +
CP a
*Treatments with the same letter are not significantly different (P<0.05)
93.3
80
Agrisure
Viptera 3111 a
DISCUSSION
isoline + CP b
isoline b
*Treatments with the same letter are not significantly different (P<0.05)
Foliar damage by Spodoptera frugiperda
4.97
Davis Scale
5
3.87
4
3
2
1.34
1.13
1
0
Agrisure 3000
GT a
Agrisure 3000
GT + CP a
Isoline + CP
b
Plants with damage (%)
Fig. 1. Foliar damage and plants with damage by fall armyworm and corncob damage and
ears with damage by corn earworm in Agrisure Viptera 3111 and isoline corn at El Dorado,
Culiacán; Sinaloa. CP= Crop Protection.
 Agrisure 3000 GT and Agrisure Viptera 3111 hybrids significantly reduced
foliar damage (Davis scale) and % plants damaged by fall armyworm S.
frugiperda. and corncob lesion size and % cobs damaged by corn earworm,
H zea, while the isolines were highly susceptible, with a greater number of
plants with injuries and higher foliar and corncob damage at Culiacan and
Navolato (Figs. 1 and 2).
 This evaluation shows that the GM corn with B. thuringiensis toxin provides
permanent protection and not seriously affected by fall armyworm and corn
earworm, while insecticidal control to prevent ear damage in field corn is
difficult and generally not cost effective and does not significantly reduce
fall armyworm damage.
2.2
Ears with damage (%)
Corncob damage by Helicoverpa zea
0
Agrisure
Viptera 3111 a
*Treatments with the same letter are not significantly different (P<0.05)
Two GM corn hybrids were used for this research; Agrisure Viptera 3111 and
Agrisure 3000 GT, both effective to control Spodoptera frugiperda and
Helicoverpa zea and their respective isolines provided by Syngenta Agro S.A.
Research was carried out at El Dorado and Navolato, Sinaloa; Mex., using an
experimental design with 8 treatments that included insecticide control(CP) and 4
replicates. Davis scale (Davis et al. 1992); (1=no damage to 9= severe damage)
was used to evaluate fall armyworm and length (cm) of damaged corncobs for
corn earworm evaluation. A proc ANOVA and a Tukey (P< 0.05) multiple range
tests was conducted using the SAS statistic software (SAS, 2002) for variables
analyzed.
56.7
Plants with leaf damage by Spodoptera frugiperda
77.8
80
66.7
60
40
20
13.3
7.8
0
Agrisure 3000
GT a
Isoline b
Agrisure 3000
GT + CP a
Isoline + CP
b
Isoline b
*Treatments with the same are not significantly different (P<0.05)
*Treatments with the same letter are not significantly different (P<0.05)
 Bt Agrisure Viptera 3111 and Agrisure 3000 GT, probe to be resistant to
both pests, increasing the chances to obtain a better grain quality and higher
yield.
Ears with damage by Helicoverpa zea
5.5
5
4.37
4
3
2
1
0.45
0.27
0
Agrisure 3000
GT a
Agrisure 3000
GT + CP a
isoline + CP b
isoline b
*Treatments with the same letter are not significantly different (P<0.05)
Ears with damage (%)
•Bruck, J. D., Lopez, M. D., Lewis L. C., Prasifka J. R. and R. D. Gunnarson.
2006. Effects of Transgenic Bacillus thuringiensis Corn and Permethrin on
Nontarget Arthropods. J. Agric. Urban Entomol. 23(3): 111-124.
•Davis, F. M.; S. S. NG. and W. P. Williams. 1992. Visual rating scales for
screening whorl-stage corn for resistance to fall armyworm. Miss. Agric. Agric.
For. Exp. Sta. Technical Bull. 186. 1-9 Pag.
•S.A.S. Institute. 2002. The SAS System for Windows, Release 9.0. SAS,
Institute, Cary N. C. U.S.A.
•Silva, C. C. A. 2005. Maíz Genéticamente Modificado. AGRO-BIO. Bogotá,
Colombia. Pág. 60.
6
Gallery (cm)
LITERATURE CITED
Corncob damage by Helicoverpa zea
96.7
100
100
80
60
56.7
36.7
40
20
0
Agrisure 3000
GT a
Agrisure 3000
GT + CP a
isoline + CP b
isoline b
*Treatments with the same letter are not significantly different (P<0.05)
Fig. 2. Foliar damage and plants with damage by fall armyworm and corncob damage and
ears with damage by corn earworm in Agrisure 3000 GT and isoline corn at Navolato,
Sinaloa. CP= Crop Protection.