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1.
Artigo | IMSEAR | ID: sea-189687

RESUMO

In preparation for a legal implementation of EU-regulation 1829/2003, the Norwegian Scientific Committee for Food Safety (VKM) has been requested by the Norwegian Directorate for Nature Management to conduct final environmental risk assessments for all genetically modified organisms (GMOs) and products containing or consisting of GMOs that are authorized in the European Union under Directive 2001/18/EC or Regulation 1829/2003/EC. The request covers scope(s) relevant to the Gene Technology Act. The request does not cover GMOs that VKM already has conducted its final risk assessments on. However, the Directorate requests VKM to consider whether updates or other changes to earlier submitted assessments are necessary. MON810 notification C/F/95/12-02 is approved under Directive 90/220/EEC for cultivation, seed production, import and processing into feeding stuffs and industrial purposes since 22 April 1998 (Commission Decision 98/294/EC). In December 1997, food and food ingredients derived from the progeny of maize line MON810 were notified under Article 5 of Regulation (EC) No 258/97 on novel foods and novel food ingredients. In addition, existing food and feed products containing, consisting of or produced from MON810 were notified according to Articles 8 and 20 of Regulation (EC) No 1829/2003 and were placed in the Community Register in 2005. Three applications for renewal of the authorisation for continued marketing of (1) existing food and food ingredients produced from MON810; (2) feed consisting of and/or containing maize MON810, and MON810 for feed use (including cultivation); and (3) food and feed additives, and feed materials produced from maize MON810 within the framework of Regulation (EC) No 1829/2003 were submitted in 2007. Maize MON810 has previously been assessed by the VKM GMO Panel commissioned by the Norwegian Directorate for Nature Management in connection with the national finalisation of the procedure of the notification C/F/95/12/02 (VKM 2007a,b). In addition, MON810 has been evaluated by the VKM GMO Panel as a component of several stacked GM maize events (VKM 2005a,b,c, VKM 2007c, VKM 2008, VKM 2009, VKM 2012). Due to the publication of updated guidelines for environmental risk assessments of genetically modified plants and new scientific literature, the VKM GMO Panel has decided to deliver an updated environmental risk assessment of MON810. The environmental risk assessment of the maize MON810 is based on information provided by the applicant in the notification C/F/95/12/02 and application EFSA/GMO/RX/MON810, and scientific comments from EFSA and other member states made available on the EFSA website GMO Extranet. The risk assessment also considered other peer-reviewed scientific literature as relevant. The VKM GMO Panel has evaluated MON810 with reference to its intended uses in the European Economic Area (EEA), and according to the principles described in the Norwegian Food Act, the Norwegian Gene Technology Act and regulations relating to impact assessment pursuant to the Gene Technology Act, Directive 2001/18/EC on the deliberate release into the environment of genetically modified organisms, and Regulation (EC) No 1829/2003 on genetically modified food and feed. The Norwegian Scientific Committee for Food Safety has also decided to take account of the appropriate principles described in the EFSA guidelines for the risk assessment of GM plants and derived food and feed (EFSA 2006, 2011a), the environmental risk assessment of GM plants (EFSA 2010), the selection of comparators for the risk assessment of GM plants (EFSA 2011b), and for the post-market environmental monitoring of GM plants (EFSA 2006, 2011c). The scientific risk assessment of maize MON810 include molecular characterisation of the inserted DNA and expression of the target protein, comparative assessment of agronomic and phenotypic characteristics, unintended effects on plant fitness, potential for gene transfer, interactions between the GM plant and target and non-target organisms, effects on biogeochemical processes and evaluations of the post-market environmental plan. In line with its mandate, VKM emphasised that assessments of sustainable development, societal utility and ethical considerations, according to the Norwegian Gene Technology Act and Regulations relating to impact assessment pursuant to the Gene Technology Act, shall not be carried out by the Panel on Genetically Modified Organisms. The genetically modified maize MON810 was developed to provide protection against certain lepidopteran target pests, including European corn borer (Ostrinia nubilalis) and species belonging to the genus Sesamia. Protection is achieved through expression in the plant of the insecticidal Cry protein, Cry1Ab, derived from Bacillus thuringiensis ssp. kurstaki, a common soil bacterium. Molecular characterisation Appropriate analysis of the integration site including flanking sequences and bioinformatics analyses have been performed to analyse the construct integrated in the GM plant. Updated bioinformatics analyses revealed that one ORF shared sequence similarity to a putative HECT-ubiquitin ligase protein. The VKM GMO Panel found no safety implications from the interruption of this gene sequence. Analyses of leaf, grains, whole plant tissue and pollen from the maize MON 810 demonstrated that the Cry1Ab protein is expressed at very low levels in all tissues tested and constitutes less than 0.001% of the fresh weight in each tissue. The cry1Ab gene is the only transgene expressed in line MON 810 and was expressed highest in the leaves. The stability of the genetic modification has been demonstrated over several generations. Event MON810 and the physical, chemical and functional characteristics of the proteins have previously been evaluated by The VKM Panel on Genetically Modified Organisms, and considered satisfactory (VKM 2007a,b). Comparative assessment: Comparative analyses of data from field trials located at representative sites and environments in the USA and Europe indicate that maize MON810 is agronomically and phenotypically equivalent to the conventional counterpart and commercially available reference varieties, with the exception of the lepidopteran-protection trait, conferred by the expression of the Cry1Ab protein. The field evaluations support a conclusion of no phenotypic changes indicative of increased plant weed/pest potential of MON810 compared to conventional maize. Evaluations of ecological interactions between maize MON810 and the biotic and abiotic environment indicate no unintended effects of the introduced trait on agronomic and phenotypic characteristics. Environmental risk: There are no reports of the target lepidopteran species attaining pest status on maize in Norway. Since there are no Bt-based insecticides approved for use in Norway, and lepidopteran pests have not been registered in maize, issues related to resistance evolution in target pests are not relevant at present for Norwegian agriculture. Published scientific studies show no or negligible adverse effects of Cry1Ab protein on non-target arthropods that live on or in the vicinity of maize plants. Cultivation of maize MON810 is not considered to represent a threat to the prevalence of red-listed species in Norway. Few studies have been published examining potential effects of Cry1Ab toxin on ecosystems in soil, mineralization, nutrient turnover and soil communities. Some field studies have indicated that root exudates and decaying plant material containing Cry proteins may affect population size and activity of rhizosphere organisms (soil protozoa and microorganisms). Most studies conclude that effects on soil microorganisms and microbial communities are transient and minor compared to effects caused by agronomic and environmental factors. However, data are only available from short term experiments and predictions of potential long term effects are difficult to deduce. Few studies have assessed the impact of Cry proteins on non-target aquatic arthropods and the fate of these proteins in senescent and decaying maize detritus in aquatic environments. However, exposure of non-target organisms to Cry proteins in aquatic ecosystems is likely to be very low, and potential exposure of Bt toxins to non-target organisms in aquatic ecosystems in Norway is considered to be negligible. Maize is the only representative of the genus Zea in Europe, and there are no cross-compatible wild or weedy relatives outside cultivation with which maize can hybridise and form backcross progeny. Vertical gene transfer in maize therefore depends on cross-pollination with other conventional or organic maize varieties. In addition, unintended admixture of genetically modified material in seeds represents a possible way for gene flow between different crop cultivations. The risk of pollen flow from maize volunteers is negligible under Norwegian growing conditions. In addition to the data presented by the applicant, the VKM GMO Panel is not aware of any scientific report of increased establishment and spread of maize MON810 and any change in survival (including over-wintering), persistence and invasiveness capacity. Because the general characteristics of maize MON810 are unchanged, insect resistance are not likely to provide a selective advantage outside cultivation in Norway. Since MON810 has no altered agronomic and phenotypic characteristics, except for the specific target pest resistance, the VKM GMO Panel is of the opinion that the likelihood of unintended environmental effects due to the establishment and survival of maize MON810 will be no different to that of conventional maize varieties in Norway. Overall conclusion: The VKM GMO Panel concludes that cultivation of maize MON810 is unlikely to have any adverse effect on the environment in Norway.

2.
Artigo | IMSEAR | ID: sea-189583

RESUMO

The Norwegian Environment Agency (NEA) and the Norwegian Food Safety Authority (NFSA) requested the Norwegian Scientific Committee for Food Safety (Vitenskapskomiteen for mattrygghet, VKM) for an opinion of potential risks to biodiversity and agriculture in Norway associated with import of seeds for sowing and cultivation of insect-resistant and herbicide tolerant genetically modified maize Bt11 under Directive 2001/18/EC (Notification C/F/96.05.10). The notification is still pending for authorisation in the European Union. VKM is also requested to assess the applicant´s post-market environmental monitoring plan, and the management measures suggested in the draft implementing decision of the European Commission. As the scope of the notification does not cover food and feed uses of maize Bt11, VKM was not asked for a health risk assessment of maize Bt11. However, VKM has decided to update a previous safety evaluation of the food and feed uses of maize Bt11 and derived products (VKM, 2014). VKM appointed a working group consisting of members from the Panel on Genetically Modified Organisms, the Panel on Alien Organisms and trade in Endangered Species (CITES) and the VKM staff to answer the requests. The Panel on Genetically Modified Organisms assessed and approved the final report. The genetically modified maize Bt11 was developed to provide protection against certain lepidopteran target pests, such as the European corn borer (ECB, Ostrinia nubilalis), and some species belonging to the genus Sesamia . The insect resistence is achieved by the expression of a truncated form of a Cry1Ab protein encoded by a modified cry1Ab gene derived from the soil microorganism Bacillus thuringiensis subsp kurstaki HD-1. Maize Bt11 also expresses the phosphinothricin - N - ace tyltransferase (pat) gene, derived from the soil microorganism Streptomyces viridochromogenes strain Tu494, which encodes the enzyme: phosphinothricin acetyl transferase (PAT). PAT protein confers tolerance to the herbicidal active substance glufosinate-ammonium. The PAT protein expressed in Bt11 was used as a selectable marker to facilitate the selection process of transformed plant cells and is not intended for weed management purposes. Since the scope of the notification C/F/96.05.10 does not cover the use of glufosinate-ammonium-containing herbicides on maize Bt11, potential effects due to the use of such herbicides on maize Bt11 are not considered by VKM. In delivering its scientific opinion, VKM considered relevant peer-reviewed scientific publications and information provided by the applicant in the notification C/F/96.05.10, the renewal application EFSA/GMO/RX/Bt11, and scientific opinions and comments from EFSA and other EU-member states. VKM has evaluated maize Bt11 with reference to its intended uses in the European Economic Area (EEA), and according to the principles described in the Norwegian Food Act, the Norwegian Gene Technology Act and regulations relating to impact assessment pursuant to the Gene Technology Act, Directive 2001/18/EC on the deliberate release into the environment of genetically modified organisms, and Regulation (EC) No 1829/2003 on genetically modified food and feed. The Norwegian Scientific Committee for Food Safety has also decided to take account of the appropriate principles described in the EFSA guidelines for the risk assessment of GM plants and derived food and feed (EFSA 2011a), the environmental risk assessment of GM plants (EFSA 2010a), selection of comparators for the risk assessment of GM plants (EFSA, 2011b) and for the post-market environmental monitoring of GM plants (EFSA, 2011c). The scientific risk assessment of maize Bt11 includes molecular characterisation of the inserted DNA and expression of novel proteins, comparative assessment of agronomic and phenotypic characteristics, nutritional assessments, toxicology and allergenicity. An evaluation of unintended effects on plant fitness, potential for gene transfer, interactions between the GM plant and target and non-target organisms, effects on biogeochemical processes, the post-market environmental monitoring plan and coexistence measures at the farm level has also been undertaken. It is emphasised that the VKM mandate does not include assessments of contribution to sustainable development, societal utility and ethical considerations, according to the Norwegian Gene Technology Act and Regulations relating to impact assessment pursuant to the Gene Technology Act. These considerations are therefore not part of the risk assessment provided by the VKM. Molecular Characterization: Appropriate analyses of the integration site, inserted DNA sequence, flanking regions, and bioinformatics have been performed. The molecular characterisation reported by the applicant shows that the DNA-fragment containing the cry1Ab and pat genes, is integrated as a single copy at a single locus in the nuclear genome of maize Bt11 and that it is stably inherited as a dominant trait. VKM considers the molecular characterisation of maize Bt11 satisfactory. Comparative Assessment: Comparative analyses of data from field trials located at representative sites and environments in North America and Europe indicates that maize Bt11 is compositionally equivalent to its conventional counterpart, with the exception of the herbicide tolerance and insect resistance traits, conferred by the expression of the PAT and Cry1Ab proteins. However, data on the amino acid tryptophan, is only given in one out of six studies. Based on current knowledge, VKM concludes that maize Bt11 is compositionally equivalent to conventional maize. The data provided by the applicant are not sufficient to show that Bt11 maize is phenotypically and agronomically equivalent to conventional near-isogenic maize lines. The agronomic assessment data are provided from one growing season in the North America and one growing season in France. This is not considered to be sufficient for representative testing of agricultural environments. Food and Feed Risk Assessment: Whole food feeding studies have not indicated any adverse health effects of maize Bt11. These studies further support that maize Bt11 is nutritionally equivalent to conventional maize. The Cry1Ab and PAT proteins do not show sequence resemblance to other known toxins or IgE allergens, nor have they been reported to cause IgE mediated allergic reactions. Some studies have however indicated a potential role of Cry-proteins as adjuvants in allergic reactions. Based on current knowledge, the VKM concludes that maize Bt11 is nutritionally equivalent to conventional maize varieties. It is unlikely that the Cry1Ab and PAT proteins will introduce a toxic or allergenic potential in food or feed based on maize Bt11 compared to conventional maize. Environmental Risk Assessment: Maize is the only representative of the genus Zea in Europe, and there are no cross-compatible wild or weedy relatives outside cultivated maize with which maize can hybridise and form backcross progeny. Vertical gene transfer in maize therefore depends on cross-pollination with other conventional or organic maize varieties. In addition, unintended admixture of genetically modified material in seeds represents a possible way for gene flow between different crop cultivations. The risk of pollen flow from maize volunteers is negligible under Norwegian growing conditions. Since maize Bt11 has no altered agronomic and phenotypic characteristics, except for the specific target insect resistance and herbicide tolerance, the likelihood of unintended environmental effects as a consequence of spread of genes from maize Bt11 is considered to be extremely low. There are no reports of the target lepidopteran species attaining pest status on maize in Norway. Since there are no Bt-based insecticides approved for use in Norway, and lepidopteran pests have not been registered in maize, issues related to resistance evolution in target pests are not relevant at present for Norwegian agriculture. Published scientific studies showed that the likelihood of negative effects of Cry1Ab protein on non-target arthropods that live on or in the vicinity of maize plants is low. In Norway, the maize cultivation is marginal. The total crop area of forage maize is estimated to 2000-2800 decares, equivalent to less than 0.1% of the areas with cereal crops. The area of individual fields is limited by the topography such that the quantity of maize pollen produced under flowering is also limited. The potential exposure of Cry1Ab-containing maize pollen on non-target lepidopteran species in Norway is therefore negligible. Cultivation of maize Bt11 is not considered to represent a threat to the prevalence of red-listed species in Norway. Exposure of nontarget organisms to Cry proteins in aquatic ecosystems is likely to be very low, and potential exposure of Cry proteins to non-target organisms in aquatic ecosystems in Norway is considered to be negligible. VKM concludes that, although the data on the fate of the Cry1Ab protein and its potential interactions in soil are limited, the relevant scientific publications analysing the Cry1Ab protein, together with the relatively broad knowledge about the environmental fate of other Cry1 proteins, do not indicate significant direct effects on the soil environment. Despite limited number of studies, most studies conclude that effects on soil microorganisms and microbial communities are transient and minor compared to effects caused by agronomic and environmental factors. However, data are only available from short-term experiments and predictions of potential long-term effects are difficult to deduce. Coexistence: VKM concludes that separation distances of 200 meters most likely will ensure coexistence between genetically modified maize and conventional and organic maize varieties in Norway. Overall Conclusion: Based on current knowledge, VKM concludes that maize Bt11 is nutritionally equivalent t

3.
Artigo | IMSEAR | ID: sea-189537

RESUMO

In preparation for a legal implementation of EU-regulation 1829/2003, the Norwegian Scientific Committee for Food Safety (VKM) has been requested by the Norwegian Environment Agency and the Norwegian Food Safety Authority (NFSA) to conduct final food/feed and environmental risk assessments for all genetically modified organisms (GMOs) and products containing or consisting of GMOs that are authorized in the European Union under Directive 2001/18/EC or Regulation 1829/2003/EC. The request covers scope(s) relevant to the Gene Technology Act. The request does not cover GMOs that VKM already has conducted its final risk assessments on. However, the Agency and NFSA requests VKM to consider whether updates or other changes to earlier submitted assessments are necessary. The insect-resistant and glyphosate-tolerant genetically modified maize MON 88017 x MON 810 from Monsanto (Unique Identifier DAS-MON 88017-3 x MON-ØØ81Ø-6) was approved under Regulation (EC) No 1829/2003 in the EU for food and feed uses, import and processing on 28th of July 2010 (Commission Decision 2010/429/EC). Genetically modified maize MON 88017 x MON 810 has previously been risk assessed by the VKM Panel on Genetically Modified Organisms (GMO), commissioned by the Norwegian Food Safety Authority related to the EFSA public hearing of the application in 2007 (VKM 2007a). In addition, MON 88017 and MON 810 has been evaluated by the VKM GMO Panel as single events and as a component of several stacked GM maize events and Regulation (EC) 1829/2003 and Directive 2001/18/EC (VKM 2005a,b,c, VKM 2007b,c,d, VKM 2008, VKM 2009, VKM 2010 a,b,c, VKM 2012, VKM 2013, VKM 2016). The food/feed and environmental risk assessment of the maize MON 88017 x MON 810 is based on information provided by the applicant in the application EFSA/GMO/CZ/2006/33 and scientific comments from EFSA and other member states made available on the EFSA website GMO Extranet. The risk assessment also considered other peer-reviewed scientific literature as relevant. The VKM GMO Panel has evaluated MON 88017 x MON 810 with reference to its intended uses in the European Economic Area (EEA), and according to the principles described in the Norwegian Food Act, the Norwegian Gene Technology Act and regulations relating to impact assessment pursuant to the Gene Technology Act, Directive 2001/18/EC on the deliberate release into the environment of genetically modified organisms, and Regulation (EC) No 1829/2003 on genetically modified food and feed. The Norwegian Scientific Committee for Food Safety has also decided to take account of the appropriate principles described in the EFSA guidelines for the risk assessment of GM plants and derived food and feed (EFSA 2011a), the environmental risk assessment of GM plants (EFSA 2010), selection of comparators for the risk assessment of GM plants (EFSA 2011b) and for the post-market environmental monitoring of GM plants (EFSA 2011c). The scientific risk assessment of maize MON 88017 x MON 810 include molecular characterisation of the inserted DNA and expression of novel proteins, comparative assessment of agronomic and phenotypic characteristics, nutritional assessments, toxicology and allergenicity, unintended effects on plant fitness, potential for gene transfer, effects on biogeochemical processes and interactions between the GM plant and target and non-target organisms. It is emphasized that the VKM mandate does not include assessments of contribution to sustainable development, societal utility and ethical considerations, according to the Norwegian Gene Technology Act and Regulations relating to impact assessment pursuant to the Gene Technology Act. These considerations are therefore not part of the risk assessment provided by the VKM Panel on Genetically Modified Organisms. Likewise, the VKM mandate does not include evaluations of herbicide residues in food and feed from genetically modified plants. The hybrid maize MON 88017 x MON 810 was produced by conventional crosses between inbred lines containing MON 88017 and MON 810 events to combine resistance to certain coleopteran and lepidopteran pests, and to confer tolerance towards glyphosate-containing herbicides. Maize MON 88017 was developed to express a modified Cry3Bb1 insecticidal protein, derived from Bacillus thuringiensis subsp. kumamotoensis , which confers protection against coleopteran target pests belonging to the genus Diabrotica such as Western corn rootworm ( Diabrotica virgifera virgifera ). MON 88017 is also developed to provide tolerance to the herbicidal active substance glyphosate by the introduction of a gene coding for the enzyme 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS), from Agrobacteri um tumefaciens strain CP4 (CP4 EPSPS). Maize MON 810 expresses the Cry1Ab insecticidal protein, derived from Bacillus thuringiensis subsp. k u rstaki, which confers protection against lepidopteran pests such as Ostrinia nubilaris and species belonging to the genus Sesamia. Molecular characterisation Southern and PCR analyses indicate that the recombinant inserts in the single maize events MON 88017 and MON 810 are retained in the stacked event MON 88017 x MON 810. Genetic stability of the inserts has previously been demonstrated in the single events. The levels of CP4 EPSPS, Cry3Bb1 and Cry1Ab proteins in grain and forage from the stacked event are comparable to the levels in the corresponding single events. Phenotypic analyses also indicate stability of the insect resistance and herbicide tolerance traits of the stacked event. Based on current knowledge and the previous assessments of the parental maize events, the VKM GMO Panel considers the molecular characterisation of maize MON 88017 x MON 810 satisfactory. Comparative assessment The applicant has performed comparative analyses of data from field trials located at representative sites and environments in USA during the 2002 growing season. With the exception of small intermittent variations and the insect resistance and herbicide tolerance conferred by the CP4 EPSPS, Cry3Bb1 and Cry1Ab proteins, the results showed no biologically relevant differences between maize stack MON 88017 x MON 810 and its conventional counterpart. Based on the assessment of available data, the VKM GMO Panel concludes that maize MON 88017 x MON 810 is compositionally, agronomically and phenotypically equivalent to its conventional counterpart, except for the new proteins. Food and feed safety assessment A whole food feeding study on broilers indicates no adverse health effects of maize MON 88017 x MON 810, and shows that it is nutritionally equivalent to conventional maize varieties. The Cry3Bb1, Cry1Ab and CP4 EPSPS proteins do not show relevant sequence resemblance to other known toxins or IgE-allergens, nor have they been reported to cause IgE-mediated allergic reactions. However, some studies have indicated a potential role of Cry-proteins as adjuvants in allergic reactions. Based on current knowledge, the VKM GMO Panel concludes that maize MON 88017 x MON 810 is nutritionally equivalent to conventional maize varieties. It is unlikely that the Cry3Bb1, Cry1Ab and CP4 EPSPS proteins will cause toxic or IgE-mediated allergic reactions to food or feed based on maize MON 88017 x MON 810 compared to conventional maize. Environmental risk assessment Considering the intended uses of maize MON 88017 x MON 810, excluding cultivation, the environmental risk assessment is concerned with accidental release into the environment of viable grains during transportation and processing, and indirect exposure, mainly through manure and faeces from animals fed grains from maize MON 88017 x MON 810. Maize MON 88017 x MON 810 has no altered survival, multiplication or dissemination characteristics, and there are no indications of an increased likelihood of spread and establishment of feral maize plants in the case of accidental release into the environment of seeds from maize MON 88017 x MON 810. Maize is the only representative of the genus Zea in Europe, and there are no cross-compatible wild or weedy relatives outside cultivation. The VKM GMO Panel considers the risk of gene flow from occasional feral GM maize plants to conventional maize varieties to be negligible in Norway. Considering the intended use as food and feed, interactions with the biotic and abiotic environment are not considered by the GMO Panel to be an issue. Overall conclusion Based on current knowledge, the VKM GMO Panel concludes that maize MON 88017 x MON 810 is compositionally, nutritionally, agronomically and phenotypically equivalent to its conventional counterpart except for the new proteins. It is unlikely that the Cry3Bb1, Cry1Ab and CP4 EPSPS proteins will cause an increased risk of toxic or IgE-mediated allergic reactions to food or feed based on maize MON 88017 x MON 810 compared to conventional maize varieties. The VKM GMO Panel concludes that maize MON 88017 x MON 810, based on current knowledge, is comparable to conventional maize varieties concerning environmental risk in Norway with the intended usage.

4.
Arq. Inst. Biol ; 84: e0062015, 2017. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-887832

RESUMO

The genetically modified maize to control some caterpillars has been widely used in Brazil. The effect of Bt maize and insecticides was evaluated on the diversity of insects (species richness and abundance), based on the insect community, functional groups and species. This study was conducted in genetically modified maize MON810, which expresses the Cry1Ab protein from Bacillus thuringiensis Berliner, and conventional maize with and without insecticide sprays (lufenuron and lambda-cyhalothrin) under field conditions in Ponta Grossa (Paraná state, Brazil). Insect samplings were performed by using pitfall trap, water tray trap and yellow sticky card. A total of 253,454 insects were collected, distributed among nine orders, 82 families and 241 species. No differences were observed in the insect community based on the richness, diversity and evenness indices. Predators and pollinators were more abundant in genetically modified maize. Parasitoids, detritivores, sap-sucking herbivores and chewing herbivores were more abundant in conventional maize with insecticide sprays. Significant differences were found for the species Colopterus sp., Colaspis occidentalis (L.) and Nusalala tessellata (Gerstaecker) which were most abundant in Bt maize, and Dalbulus maidis and Condylostylus sp.2 in conventional maize.(AU)


O milho geneticamente modificado visando ao controle de lagartas tem sido amplamente utilizado no Brasil. Em estudo de campo realizado em Ponta Grossa (Paraná, Brasil), compararam-se, com base na diversidade (riqueza de espécies e abundância), os efeitos do milho Bt e do controle químico sobre a comunidade de insetos, grupos funcionais e espécies. A comunidade de insetos foi amostrada no milho geneticamente modificado MON810, que expressa a proteína Cry1Ab de Bacillus thuringiensis Berliner, e no milho convencional com e sem a aplicação de inseticidas (lufenuron e lambda-cialotrina). As amostragens foram realizadas por meio da coleta de insetos utilizando-se armadilha de queda, bandeja-d'água e cartão adesivo. Foram coletados 253.454 insetos, distribuídos em nove ordens, 82 famílias e 241 espécies. Não foram observadas diferenças na comunidade de insetos para os índices de riqueza, diversidade e equitabilidade nos tratamentos avaliados. Predadores e polinizadores foram mais abundantes no milho geneticamente modificado, e parasitoides, decompositores, sugadores e mastigadores, no milho convencional com inseticida. Diferenças significativas foram detectadas para as espécies Colopterus sp., Colaspis occidentalis (L.) e Nusalala tessellata (Gerstaecker), mais abundantes no milho Bt, e Dalbulus maidis e Condylostylus sp.2, mais abundantes no milho convencional.(AU)


Assuntos
Controle de Pragas , Zea mays , Alimentos Geneticamente Modificados , Biodiversidade
5.
Braz. j. microbiol ; 47(3): 597-602, July-Sept. 2016. graf
Artigo em Inglês | LILACS | ID: lil-788966

RESUMO

ABSTRACT In this study, the cry1Ab gene of previously characterized and Lepidoptera-, Diptera-, and Coleoptera-active Bacillus thuringiensis SY49-1 strain was cloned, expressed and individually tested on Ephestia kuehniella (Lepidoptera: Pyralidae) and Plodia interpunctella (Lepidoptera: Pyralidae) larvae. pET-cry1Ab plasmids were constructed by ligating the cry1Ab into pET28a (+) expression vector. Constructed plasmids were transferred to an Escherichia coli BL21 (DE3) strain rendered competent with CaCl2. Isopropyl β-D-1-thiogalactopyranoside was used to induce the expression of cry1Ab in E. coli BL21(DE3), and consequently, ∼130 kDa of Cry1Ab was obtained. Bioassay results indicated that recombinant Cry1Ab at a dose of 1000 µg g-1 caused 40% and 64% mortality on P. interpunctella and E. kuehniella larvae, respectively. However, the mortality rates of Bt SY49-1 strains' spore-crystal mixture at the same dose were observed to be 70% on P. interpunctella and 90% on E. kuehniella larvae. The results indicated that cry1Ab may be considered as a good candidate in transgenic crop production and as an alternative biocontrol agent in controlling stored product moths.


Assuntos
Animais , Bacillus thuringiensis/fisiologia , Proteínas de Bactérias/genética , Expressão Gênica , Controle de Insetos , Endotoxinas/genética , Proteínas Hemolisinas/genética , Bacillus thuringiensis/ultraestrutura , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/toxicidade , Controle de Insetos/métodos , Clonagem Molecular , Endotoxinas/metabolismo , Endotoxinas/toxicidade , Proteínas Hemolisinas/metabolismo , Proteínas Hemolisinas/toxicidade , Inseticidas , Larva , Mariposas/efeitos dos fármacos
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