scholarly journals Diversity of carabid beetles (Coleoptera: Carabidae) under three different control strategies against European corn borer in maize

2013 ◽  
Vol 49 (No. 3) ◽  
pp. 146-153 ◽  
Author(s):  
F. Kocourek ◽  
P. Saska ◽  
M. Řezáč
Keyword(s):  
European Corn Borer ◽  
Control Strategies ◽  
Carabid Beetles ◽  
Bt Maize ◽  
Corn Borer ◽  
Focal Treatment ◽  
Cropping Seasons ◽  
The Impact ◽  
Insect Resistant ◽  
Mon 810

We compared three control strategies against European corn borer (Ostrinia nubilalis Hubner) in maize with respect to carabid beetles, beneficial epigeal arthropods. The impact of the focal treatment (insect resistant Bt maize MON 810) was compared with conventionally farmed and Trichogramma-treated plots at two sites (Prague-Ruzyně and Ivanovice na Hané) in the Czech Republic, replicated in three cropping seasons (2002–2004). The sampled assemblages were species-poor. The species were unevenly distributed in terms of their catch size – the communities were dominated by 7 (Ruzyně) or 3 (Ivanovice) species. No differences were found in species richness or species composition between treatments, seasons or sites, suggesting no effect of planting transgenic insect resistant Bt maize MON 810 on the assemblages of carabid beetles in the study fields.  

scholarly journals The impact of Bacillus thuringiensis technology on the occurrence of fumonisins and other mycotoxins in maize

2016 ◽  
Vol 9 (3) ◽  
pp. 475-486 ◽  
Author(s):  
J. Díaz-Gómez ◽  
S. Marín ◽  
T. Capell ◽  
V. Sanchis ◽  
A.J. Ramos
Keyword(s):  
Bacillus Thuringiensis ◽  
Fungal Infection ◽  
European Corn Borer ◽  
Insect Pests ◽  
Animal Feed ◽  
Bt Maize ◽  
Cry1ab Protein ◽  
Corn Borer ◽  
Maize Hybrids ◽  
The Impact

In many developing countries, maize is both a staple food crop and a widely-used animal feed. However, adventitious colonisation or damage caused by insect pests allows fungi to penetrate the vegetative parts of the plant and the kernels, the latter resulting in mycotoxin contamination. Maize seeds contaminated with fumonisins and other mycotoxins pose a serious threat to both humans and livestock. However, numerous studies have reported a significant reduction in pest damage, disease symptoms and fumonisin levels in maize hybrids expressing the Bacillus thuringiensis (Bt) gene cry1Ab, particularly in areas where the European corn borer is prevalent. When other pests are also present, the cry1Ab gene alone offers insufficient protection, and combinations of insecticidal genes are required to reduce damage to plants caused by insects. The combination of Cry1Ab protein with other Cry proteins (such as Cry1F) or Vip proteins has reduced the incidence of pests and, indirectly, mycotoxin levels. Maize hybrids expressing multiple Bt genes, such as SmartStax®, are less susceptible to damage by insects, but mycotoxin levels are not routinely and consistently compared in these crops. Bt maize has a greater economic impact on Fusarium toxins than aflatoxins. The main factors that determine the effectiveness of Bt hybrids are the type of pest and the environmental conditions, but the different fungal infection pathways must also be considered. An alternative strategy to reduce mycotoxin levels in crops is the development of transgenic plants expressing genes that protect against fungal infection or reduce mycotoxin levels by in situ detoxification. In this review article, we summarise what is known about the relationship between the cultivation of Bt maize hybrids and contamination levels with different types of mycotoxins.

scholarly journals Maize Plants Infestation by Fusarium spp. and Deoxynivalenol in Genetically Modified Corn Hybrid and Traditional Maize Cultivars

2011 ◽  
Vol 60 (4) ◽  
pp. 317-321 ◽  
Author(s):  
MAREK SELWET
Keyword(s):  
European Corn Borer ◽  
Genetically Modified ◽  
Pathogenic Fungi ◽  
Genetically Modified Maize ◽  
Corn Borer ◽  
Maize Cultivars ◽  
Maize Plants ◽  
Maize Cob ◽  
Grain Contamination ◽  
Mon 810

The objective of the performed investigations was to isolate pathogenic fungi from contaminated maize cobs, to assess the appearance of maize cob fusariosis and to determine grain contamination with deoxynivalenol in the cultivation of genetically modified maize containing a gene resistance against European corn borer (Ostrinia nubilalis Hbn) as well as selected non-modified cultivars. The plant material comprised the following genetically modified maize cultivar: DKC 3421 YG (MON 810) and non-modified cultivars obtained from Smolice Plant Breeding Ltd., IHAR Group: Junak (FAO 210-220), Prosna (FAO 220), SMH (FAO 230), Baca (FAO 220). Prior to harvesting, the occurrence of maize cob fusariosis was determined in the 89 (BBCH) developmental ripening stage. Microbiological assessment was carried out on grains selected from cobs characterized by various pathological symptoms. In 2008, a total of 133 isolates was obtained from the examined samples of infected maize plants, of which 51 isolates were species-identified, while in 2009, the total of 123 isolates were determined, of which 63 were species-identified. In both experimental years, the majority of isolates contained fungi from the Fusarium genus. The performed analysis of mean levels of cob contamination by fusarioses revealed that DKC 3421 YG (MON 810) and SMH (FAO 230) cultivars showed the smallest levels of contamination as well as the lowest percent of cob contamination per plant, while Junak (FAO 210-220) and Baca (FAO 220) cultivars were characterized by the highest degree of contamination. The lowest deoxynivalenol concentrations were determined in years 2008 and 2009 in the case of the DKC 3421 YG (MON 810) cultivar, whereas Prosna (FAO 220) cultivar was characterized by the highest deoxynivalenol concentration.

Frequency of alleles conferring resistance to Bt maize in French and US corn belt populations of the European corn borer, Ostrinia nubilalis

2002 ◽  
Vol 106 (7) ◽  
pp. 1225-1233 ◽  
Author(s):  
D. Bourguet ◽  
J. Chaufaux ◽  
M. Séguin ◽  
C. Buisson ◽  
J. L. Hinton ◽  
...  
Keyword(s):  
Ostrinia Nubilalis ◽  
European Corn Borer ◽  
Corn Belt ◽  
Bt Maize ◽  
Corn Borer

Effects of Nitrogen Fertility on Bt Endotoxin Levels in Maize

2007 ◽  
Vol 42 (1) ◽  
pp. 35-43 ◽  
Author(s):  
H. Arnold Bruns ◽  
Craig A. Abel
Keyword(s):  
Growth Stage ◽  
Heliothis Zea ◽  
Larval Survival ◽  
Corn Earworm ◽  
Fertility Rates ◽  
Bt Maize ◽  
Tissue Samples ◽  
Corn Borer ◽  
N Fertility ◽  
Mon 810

Three Bt maize hybrids (two with Bt event MON-810, one with Bt event DBT-418) and one nonBt maize hybrid were grown at Stoneville, MS, USA in 2002 and 2003 with N-fertility rates of 0, 112, 224, and 336 kg N/ha, respectively. Tissue samples of the 7th leaf at growth stage V5 (5 fully extended leaves) and primary ear leaf sheaths and outer ear husks at growth stage R3 (milk) were collected and analyzed for endotoxin concentrations. At V5 CrylAb Bt concentrations of the MON-810 hybrids increased whereas there were no N-fertility effects on Cry1Ac in the DBT-418 hybrid. Bioassays from tissue samples at growth stage V5 of all N-fertility treatments for both Bt events were nearly 100% fatal to southwestern corn borer larvae (Diatraea grandiosella_Dyar). Endotoxin concentrations at growth stage R3 increased in both the primary ear leaf sheaths {[Bt] = 0.0006(kg N/ha) + 0.167 r2 = 0.8817 for both MON-810 and DBT-418} and outer ear husks {[Bt] = 0.0006(kg N/ha) + 0.148) r2 = 0.9985 and [Bt] = 0.0007 (kg N/ha) + 0.16) r2 = 0.8702 for MON-810 and DBT-418, respectively} as N fertilization increased in 2003. Bioassays determined that southwestern corn borers were susceptible to even the lowest [Bt] in tissues of MON-810 at R3 but not DBT-418. Diets made from the nonBt hybrid at all stages and N-fertility rates had a nearly 80.0% larval survival rate. Because other Noctuidae pests [i.e., corn earworm (Heliothis zea (Boddie)) and fall armyworm (Spodoptera frugiperda (J. E. Smith))] of corn are more tolerant to Bt toxins, growing Bt maize under adequate levels of N-fertility may be even more important to insure maximum protection from these pests.

Estimating the impact of climate change on the occurrence of selected pests at a high spatial resolution: a novel approach

2011 ◽  
Vol 149 (2) ◽  
pp. 185-195 ◽  
Author(s):  
E. KOCMÁNKOVÁ ◽  
M. TRNKA ◽  
J. EITZINGER ◽  
M. DUBROVSKÝ ◽  
P. ŠTĚPÁNEK ◽  
...  
Keyword(s):  
Climate Change ◽  
Colorado Potato Beetle ◽  
European Corn Borer ◽  
Arable Land ◽  
Global Climate Models ◽  
Climate Change Scenarios ◽  
Pest Species ◽  
Corn Borer ◽  
Potato Beetle ◽  
The Impact

SUMMARYThe present study is focused on the potential occurrence of the Colorado potato beetle (Leptinotarsa decemlineata, Say 1824), an important potato pest, and the European corn borer (Ostrinia nubilalis, Hübner 1796), the most important maize pest, during climate change. Estimates of the current potential distribution of both pest species as well as their distribution in the expected climate conditions are based on the CLIMEX model. The study covers central Europe, including Austria, the Czech Republic, Hungary, and parts of Germany, Poland, Romania, Slovakia, Switzerland, Ukraine, Slovenia, the northern parts of Serbia, parts of Croatia and northern Italy. The validated model of the pests’ geographical distribution was applied within the domain of the regional climate model (RCM) ALADIN, at a resolution of 10 km. The weather series that was the input for the CLIMEX model was prepared by a weather generator (WG) which was calibrated with the RCM-simulated weather series (for the period of 1961–90). To generate a weather series for two future time periods (2021–50 and 2071–2100), the WG parameters were modified according to 12 climate change scenarios produced by the pattern scaling method. The standardized scenarios derived from three global climate models (HadCM, NCAR-PCM and ECHAM) were scaled by low, middle and high values of global temperature change estimated by the Model for the Assessment of Greenhouse-gas Induced Climate Change (MAGICC) model (assuming three combinations of climatic sensitivity and emission scenarios). The results of present study suggest the likely widening of the pests’ habitats and an increase in the number of generations per year. According to the HadCM-high scenario, the area of arable land affected by a third generation per season of Colorado potato beetle in 2050 is c. 45% higher, and by a second generation of the European corn borer is nearly 61% higher, compared to present levels.

scholarly journals Modeling the Impact of Cross-pollination and Low Toxin Expression in Corn Kernels on Adaptation of European Corn Borer (Lepidoptera: Crambidae) to Transgenic Insecticidal Corn

2012 ◽  
Vol 41 (1) ◽  
pp. 200-211 ◽  
Author(s):  
J. Kang ◽  
D. W. Onstad ◽  
R. L. Hellmich ◽  
S. E. Moser ◽  
W. D. Hutchison ◽  
...  
Keyword(s):  
European Corn Borer ◽  
Corn Borer ◽  
Cross Pollination ◽  
Corn Kernels ◽  
The Impact

THIRD TROPHIC LEVEL EFFECTS OF AZADIRACHTIN

1993 ◽  
Vol 125 (1) ◽  
pp. 163-165 ◽  
Author(s):  
C. McCloskey ◽  
J.T. Arnason ◽  
N. Donskov ◽  
R. Chenier ◽  
J. Kaminski ◽  
...  
Keyword(s):  
Natural Enemies ◽  
Ostrinia Nubilalis ◽  
European Corn Borer ◽  
Corn Borer ◽  
Cotesia Congregata ◽  
Third Trophic Level ◽  
Sublethal Doses ◽  
Parasitoid Development ◽  
Diadegma Terebrans ◽  
The Impact

Azadirachtin (AZA) is the principal insecticidal compound occurring in the oil of neem [Azadirachta indica (Juss.)] seed. Although many studies have been published (Schmutterer 1990) regarding the effects of AZA on herbivorous insects, little is known of the impact of this compound on the natural enemies of herbivores. Beckage et al. (1988) investigated the effects of injected AZA on Cotesia congregata (FAY) (Braconidae), a parasitoid of Manduca sexta (L.). Parasitoid development was retarded when injections of 2.5–10 μg AZA were administered to the host larva prior to the wasp's first larval ecdysis. The development of new neem-based insecticides in North America (Isman et al. 1991) has prompted the investigation of the effects of AZA on the natural enemies of pest insects that have ingested sublethal doses of the active compound. Our laboratory study was carried out with the ichneumonid parasitoid, Diadegma terebrans (Gravenhorst), and its host, the European corn borer, Ostrinia nubilalis (Hubner). AZA (>95% purity) for this study was extracted as described previously (Xie et al. 1991) from seeds collected in India.

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