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Abstract The active ingredient glyphosate is the most commercialized herbicide on the world market due to its capability in eliminating weeds. However, it can harm the development of non-target organisms and threaten environmental quality. This study analyzed the effects of potentially toxic concentrations of glyphosate on germination, growth, cell cycle and genomic stability of Lactuca sativa L., and identified the most sensitive variables for assessing the toxicity of this herbicide to this biomonitor. Seeds of L. sativa were germinated in Petri dishes containing a sheet of filter paper moistened with 5 mL of a concentration of glyphosate (1.34, 3.35, 6.70, 10.05, 13.40 mg L-1). Controls consisted of distilled water (negative) and 3 mg L-1 CuSO4 (positive). Macroscopic and microscopic variables were analyzed. The germination of L. sativa was not affected by the concentrations of glyphosate. Root length and shoot height of the plants and the mitotic index decreased from the lowest concentration tested on. The chromosomal anomaly index and frequency of micronuclei increased by 3.2 and 22 times, respectively, with the presence of the lowest concentration of glyphosate compared to the negative control. The observed phytotoxic and cytogenotoxic effects demonstrate the negative influence that glyphosate has on the development of L. sativa. Root length and microscopic variables showed the highest sensitivity. This study warns of the possible harmful effects that glyphosate can have on non-target organisms and suggests greater control over the use of this herbicide to mitigate its environmental impact.

Resumo O ingrediente ativo glifosato é o herbicida mais comercializado do mercado mundial, pela sua capacidade de eliminar as plantas daninhas. No entanto, ele pode prejudicar o desenvolvimento dos organismos não-alvo e ameaçar a qualidade do ambiente. O estudo teve como objetivo analisar os efeitos de concentrações potencialmente tóxicas de glifosato sobre a germinação, o crescimento, o ciclo celular e a estabilidade genômica de Lactuca sativa L., e identificar as variáveis mais sensíveis para avaliar a toxicidade deste herbicida ao biomonitor. Sementes de L. sativa foram germinadas em placas de Petri contendo uma folha de papel-filtro umedecida com 5 mL das concentrações de glifosato (1,34, 3,35, 6,70, 10,05, 13,40 mg L-1). Os controles consistiram em água destilada (negativo) e 3 mg L-1 de CuSO4 (positivo). Variáveis macroscópicas e microscópicas foram analisadas. A germinação de L. sativa não foi afetada pelas concentrações de glifosato. O comprimento da raiz e a altura da parte aérea das plantas e o índice mitótico reduziram desde a menor concentração testada. O índice de anomalias cromossômicas e a frequência de micronúcleos aumentaram, respectivamente, 3,2 e 22 vezes na presença da menor concentração de glifosato em comparação ao controle negativo. Os efeitos fitotóxicos e citogenotóxicos observados demonstram a interferência negativa do herbicida no desenvolvimento de L. sativa. O comprimento da raiz e as variáveis microscópicas foram as que apresentaram maior sensibilidade. Este estudo alerta sobre os possíveis efeitos prejudiciais que o glifosato pode provocar nos organismos não-alvo, sugerindo um maior controle quanto à utilização deste herbicida, a fim de mitigar o seu impacto ambiental.

RESUMO

The active ingredient glyphosate is the most commercialized herbicide on the world market due to its capability in eliminating weeds. However, it can harm the development of non-target organisms and threaten environmental quality. This study analyzed the effects of potentially toxic concentrations of glyphosate on germination, growth, cell cycle and genomic stability of Lactuca sativa L., and identified the most sensitive variables for assessing the toxicity of this herbicide to this biomonitor. Seeds of L. sativa were germinated in Petri dishes containing a sheet of filter paper moistened with 5 mL of a concentration of glyphosate (1.34, 3.35, 6.70, 10.05, 13.40 mg L-1). Controls consisted of distilled water (negative) and 3 mg L-1 CuSO4 (positive). Macroscopic and microscopic variables were analyzed. The germination of L. sativa was not affected by the concentrations of glyphosate. Root length and shoot height of the plants and the mitotic index decreased from the lowest concentration tested on. The chromosomal anomaly index and frequency of micronuclei increased by 3.2 and 22 times, respectively, with the presence of the lowest concentration of glyphosate compared to the negative control. The observed phytotoxic and cytogenotoxic effects demonstrate the negative influence that glyphosate has on the development of L. sativa. Root length and microscopic variables showed the highest sensitivity. This study warns of the possible harmful effects that glyphosate can have on non-target organisms and suggests greater control over the use of this herbicide to mitigate its environmental impact.

O ingrediente ativo glifosato é o herbicida mais comercializado do mercado mundial, pela sua capacidade de eliminar as plantas daninhas. No entanto, ele pode prejudicar o desenvolvimento dos organismos não-alvo e ameaçar a qualidade do ambiente. O estudo teve como objetivo analisar os efeitos de concentrações potencialmente tóxicas de glifosato sobre a germinação, o crescimento, o ciclo celular e a estabilidade genômica de Lactuca sativa L., e identificar as variáveis mais sensíveis para avaliar a toxicidade deste herbicida ao biomonitor. Sementes de L. sativa foram germinadas em placas de Petri contendo uma folha de papel-filtro umedecida com 5 mL das concentrações de glifosato (1,34, 3,35, 6,70, 10,05, 13,40 mg L-1). Os controles consistiram em água destilada (negativo) e 3 mg L-1 de CuSO4 (positivo). Variáveis macroscópicas e microscópicas foram analisadas. A germinação de L. sativa não foi afetada pelas concentrações de glifosato. O comprimento da raiz e a altura da parte aérea das plantas e o índice mitótico reduziram desde a menor concentração testada. O índice de anomalias cromossômicas e a frequência de micronúcleos aumentaram, respectivamente, 3,2 e 22 vezes na presença da menor concentração de glifosato em comparação ao controle negativo. Os efeitos fitotóxicos e citogenotóxicos observados demonstram a interferência negativa do herbicida no desenvolvimento de L. sativa. O comprimento da raiz e as variáveis microscópicas foram as que apresentaram maior sensibilidade. Este estudo alerta sobre os possíveis efeitos prejudiciais que o glifosato pode provocar nos organismos não-alvo, sugerindo um maior controle quanto à utilização deste herbicida, a fim de mitigar o seu impacto ambiental.

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Pyriproxyfen is a juvenile hormone analogue that is commonly used to control the immature stages of mosquitoes in both artificial and natural water reservoirs. Recently, concerns have been raised regarding the community effectiveness of pyriproxyfen in preventing vector-transmitted diseases. Such concerns have been based on the unintended effects on non-target organisms and the selection of resistant mosquito populations. This investigation was, therefore, conducted to evaluate the toxicity of pyriproxyfen to Aedes aegypti (Diptera: Culicidae) larvae and the backswimmer Buenoa amnigenus (Hemiptera: Notonectidae), a naturally occurring mosquito larvae predator. We also assessed the abilities of backswimmers exposed to sublethal levels of pyriproxyfen to prey upon mosquito larvae (L2) under three larval densities (3, 6, or 9 larvae/100 mL of water) using artificial containers. Our results revealed that pyriproxyfen killed backswimmers only at concentrations higher than 100 µg active ingredient [a.i.]/L, which is 10 times higher than that recommended for larvicidal field application (i.e, 10 µg a.i./L). The abilities of backswimmers exposed to sublethal levels of pyriproxyfen (100 µg a.i./L) to prey upon mosquito larvae were not affected. Harmful effects on the backswimmer predatory abilities were detected only at concentrations of 150 µg a.i./L and when there was a higher prey availability (i.e., 9 larvae/100 mL of water). Together, our findings indicate that the reduced community effectiveness of this insecticide derives from factors other than its detrimental effects on non-target organisms such as backswimmers.

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Worldwide pesticide usage was estimated in up to 3.5 million tons in 2020. The number of approved products varies among different countries, however, in Brazil, there are nearly 5000 of such products available. Among them, insecticides correspond to a group of mounting importance for controlling crop pests and disease-associated vectors in public health. Unfortunately, resistance to commercially approved insecticides is commonly observed, limiting the use of these products. Thus, the search for more effective and environmentally friendly products is both a challenge and a necessity since several insecticides are no longer allowed in many countries. In this review, we discuss the historical strategies used in the development of modern insecticides, including chemical structure alterations, mechanism of action and their impact on insecticidal activity. The environmental impact of each pesticide class is also discussed, with persistence data and activity on non-target organisms, along with the human toxicological effect. By tracing the historical route of discovery and development of blockbuster pesticides like DDT, pyrethroids and organophosphates, we also aim to categorize and relate the successful chemical alterations and novel pesticide development strategies that resulted in safer alternatives. A brief discussion on the Brazilian registration procedure and a perspective of insecticides currently approved in the country was also included.

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Forestry pest management includes biological and chemical methods of pest control. Using insecticides and natural enemies can be compatible in forest pest management programs. The compatibility of the predatory stink bug Podisus distinctus with the insecticide indoxacarb, used in forestry, needs to be evaluated in Brazil. This study investigated the mortality, survival, respiration, preference, prey consumption, and locomotor activity of P. distinctus adults exposed to indoxacarb. In concentration-mortality bioassays, the lethality of indoxacarb (LC50 = 2.62 g L-1 and LC90 = 6.11 g L-1) was confirmed in P. distinctus adults. The survival rate was 100% in predator insects not exposed to indoxacarb, declining to 40.7% in predator insects exposed to 2.62 g L-1 and 0.1% in predators treated with 6.11 g L-1. Indoxacarb reduced the respiration of P. distinctus from 18.45 to 14.41 µL CO2 h-1 at 2.62 g L-1 for up to 3 h after insecticide exposure, inhibiting food consumption and displaying hyperexcitation. The harmful effects of indoxacarb to the natural enemy suggest that it should be better assessed for use with P. distinctus for pest management in forestry.

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The control of defoliating caterpillars in forestry includes the use of insecticides and releases of the predatory bug Podisus nigrispinus, but some compounds may affect non-target natural enemies, which need evaluation of risk assessment. This research investigates the survival, preference, and prey consumption of P. nigrispinus adults fed with prey treated with the lethal concentration (LC50) of Bacillus thuringiensis (Bt), permethrin, tebufenozide, and thiamethoxam. Moreover, midgut histopathology of P. nigrispinus fed with preys treated with LC50 of each insecticide was investigated. The insecticides Bt, permethrin, and thiamethoxam reduce the survival and the prey consumption in P. nigrispinus fed with preys contaminate with these chemicals. However, the four tested insecticides, including tebufenozide, cause histological changes such as irregular epithelial architecture, cytoplasm vacuolization, and release of cell fragments in the midgut lumen of P. nigrispinus. The sublethal effects of Bt, permethrin, tebufenozide, and thiamethoxam to the natural enemy suggest that they should be better evaluated to be used together with P. nigrispinus for integrated pest management in forestry.

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Phytoremediation is a technique that reduces the impact and environmental toxicity of toxic agents. Plectranthus neochilus, a species of aromatic plant, has already promoted phytoremediation of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D). In addition, it was unclear whether the degradation of 2,4-D alone allows for a non-toxic environment (decontamination efficiency). Therefore, the aim of the present study was to verify the changes of the volatile compounds and concentrated essential oil of P. neochilus after phytoremediation of 2,4-D and the subsequent antibacterial activity of this essential oil concentrate. In addition, the toxicity of the plant's tea and the aqueous medium (waste) after the decontamination of 2,4-D was analyzed. The exposure to 2,4-D did not cause many changes in the volatile compounds, nor in the essential oil concentrate from the plant. Therefore, this essential oil concentrate can be used as an antimicrobial after phytoremediation. Regarding the use of this plant in tea form, it was found to be unsafe, even after phytoremediation, as this tea was toxic to the Drosophila melanogaster model (death of up to 100% of flies). The aqueous medium after 2,4-D phytoremediation became less toxic than the initial one (bioassays with Artemia salina and Allium cepa in the waste groups). However, the efficiency of phytoremediation with this plant must be improved. Therefore, we are performing new studies with P. necohilus and 2,4-D in aqueous medium.

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Podisus nigrispinus Dallas (Heteroptera: Pentatomidae) preys on insect pests in eucalyptus plantations where it can be exposed to insecticides used in pest control. The effect of insecticides on non-target natural enemies requires further study. The objective of the present study was to evaluate the side-effects of Bacillus thuringiensis (Bt), permethrin, tebufenozide and thiamethoxam on third instar nymphs of the predator P. nigrispinus in the laboratory. The toxicity of insecticides for this insect was determined by estimating their lethal concentrations. Podisus nigrispinus behavior after exposure to insecticides was analyzed using a video tracking system and the respiratory rate with a respirometer. Prey/nymph consumption was assessed after 24 h of starvation. The preference of P. nigrispinus nymphs, for prey treated or not with the insecticides, was evaluated in free choice tests. The insecticides Bt [LC50 = 1.10(0.83-1.46) mg mL-1], permethrin [LC50 = 0.25(0.17-0.34) mg mL-1], tebufenozide [LC50 = 5.71(4.17-7.57) mg mL-1] and thiamethoxam [LC50 = 0.04(0.02-0.06) mg mL-1] are toxic to P. nigrispinus nymphs. Bt and the insecticides tebufenozide, permethrin and thiamethoxam reduced the respiratory rate of P. nigrispinus. The insecticides permethrin, tebufenozide and thiamethoxam affect the locomotion of this insect's nymphs. Prey treated with Bt, permethrin and thiamethoxam are less preferred by P. nigrispinus. The survival of the nymphs of this predator was 93.3%, 66.7%, 56.6%, 0% and 0% in the control, tebufenozide, Bt, permethrin and thiamethoxam treatments, respectively. In addition, the reduction of prey consumption, treated with neurotoxic insecticides, reduces the predatory potential of this natural enemy. Bt and tefubenozide present low toxicity for P. nigrispinus, but the neurotoxic products have low compatibility with this natural enemy and, therefore, are not recommended, with this predator in the management of forest insect pests.

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The objective of this study was to evaluate the effect of the entomopathogenic fungus Beauveria bassiana, used in large field crops, and of the pomegranate Punica granatum aqueous extract, with insecticidal potential for insect control, on the quality of Africanized Apis mellifera queens. The control sample was composed of sterile distilled water with Tween®. The treatments were incorporated into a voile fabric, covered with an acrylic plate and packed with queen rearing nucleus hive, so the worker bees could be in contact with control agents (B. bassiana and P. granatum). In the next day, frames with 30 cell cups for queen rearing with larvae were introduced to produce queens, which were monitored at moment of emergency. Measurements included live weight, wing size, abdomen size, thorax size, the time of emergence, and analysis of the breeding area size. Histological analyses of the hypopharyngeal glands of attendant worker bees and of the midgut of virgin queens were performed. There was no reduction in the weight of queens, no changes in the length, width, and height of their thoraxes, no changes in the width and length of the wing, and no changes in total length. However, B. bassiana increased the weight of the queens and reduced emergency time. The control agents did not interfere in villi height and breeding area. No differences were found in tissues when the treatments were compared with their control. P. granatum extract and the fungus B. bassiana did not interfere in the quality of Africanized A. mellifera queens.(AU)

O objetivo foi avaliar o efeito do fungo entomopatogênico Beauveria bassiana, usado em grandes culturas, e o extrato aquoso de romã Punica granatum, com potencial efeito inseticida para o controle de insetos, sobre a qualidade de rainhas de Apis mellifera africanizadas. A testemunha foi composta por água destilada esterilizada com Tween®. Os tratamentos foram incorporados em um tecido tipo gaze, envolto em uma placa de acrílico e acondicionados no interior de colônias tipo minirrecrias, para que as operárias entrassem em contato com o agente testado (B. bassiana and P. granatum). No dia seguinte foram introduzidos sarrafos com 30 cúpulas com larvas para produção de rainhas, as quais foram monitoradas à emergência, mensurando peso vivo, comprimento e largura da asa e do abdome, comprimento, largura e altura do tórax, tempo de emergência e área de cria. Análises histológicas das glândulas hipofaringeanas das operárias amas e do mesêntero das rainhas virgens também foram realizadas. Não houve redução no peso das rainhas e no comprimento do tórax e tampouco alteração na largura e altura do tórax, comprimento e largura do abdome, comprimento e largura da asa e comprimento total. No entanto B. bassiana induziu aumento no peso das rainhas e redução no tempo de emergência. Os agentes não interferiram na altura das vilosidades do mesêntero e na área de cria. Na análise histológica não foram observadas diferenças nos tecidos quando os tratamentos foram comparados com as respectivas testemunhas. O extrato de P. granatum e o fungo B. bassiana não interferiram na qualidade de rainhas de A. mellifera africanizada.(AU)

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BACKGROUND: Thiamethoxam, when applied as a seed treatment, can contaminate plant products, such as extrafloral nectar, and have non-target effects on beneficial arthropods. This study assessed the non-target effects of thiamethoxam applied to cotton seed on the life history parameters of the predators Chrysoperla externa (Neuroptera: Chrysopidae) and Harmonia axyridis (Coleoptera: Coccinellidae). RESULTS: Exposure of C. externa larvae to plants grown from thiamethoxam-treated seeds caused sublethal and transgenerational effects. Thiamethoxam treatment doubled the proportion of pharate adults and reduced egg fertility in C. externa F0 and F1 generations. In addition, the insecticide prolonged pupal developmental time in the C. externa F1 generation. Thiamethoxam treatment also had a transgenerational effect on exposed H. axyridis larvae, reducing pupal survival in the F1 generation. In the adult bioassay, thiamethoxam treatment reduced egg fertility of C. externa, prolonged the larval period, and reduced both fecundity and egg fertility of the F1 generation. Thiamethoxam also caused transgenerational effect on H. axyridis adults, reducing larval survival of the F1 generation. CONCLUSION: Thiamethoxam seed treatment was harmful for both predators, but C. externa was more affected by the insecticide than H. axyridis. © 2018 Society of Chemical Industry.

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Pharmaceutical discharges into the aquatic ecosystem are of environmental concern and sewage treatment plants (STPs) have been pointed out as the major source of these compounds to coastal zones, where oceanic disposal of sewage occurs through submarine outfalls. Diclofenac (DCF) is one of the most frequently detected pharmaceuticals in water, but little is known about the effects on marine organisms. In this study, we employed a tiered approach involving the determination of environmental concentrations of DCF in marine water and the adverse biological effects for fertilization, embryo-larval development and biomarker responses of the mussel Perna perna. Results indicate that effects in fertilization rate and embryo-larval development were found in the order of mg·L-1. However, low concentrations of DCF (ng·L-1) significantly decreased the lysosomal membrane stability and COX activity, as well as triggered DNA damage, oxidative stress and changes in antioxidant defenses. Our results point to an environmental hazard at coastal ecosystems and suggest the need for improvements in the treatment of domestic wastewater aiming to reduce DCF concentrations, as well as regulation on current environmental legislation and monitoring of aquatic ecosystems.

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Em lavoura de arroz irrigado, é utilizada uma grande quantidade de agroquímicos que, dependendo da sua persistência a campo e toxicidade, podem contaminar corpos d’água e afetar organismos vivos. Com o objetivo de determinar o efeito de concentrações de campo dos herbicidas Clomazone, Quinclorac, Metsulfuron-methyl e Propanil na comunidade zooplanctônica (Cladocera, Copepoda e Rotifera), conduziu-se um experimento em viveiros de aqüicultura, de março a maio de 2005, na estação do outono. Nos dias 1°, 2°, 3°, 7°, 10°, 18°, 31° e 51° após a aplicação dos herbicidas, foram coletadas amostras de água para se determinarem parâmetros físico-químicos da água, concentração dos herbicidas e comunidade zooplanctônica. Os parâmetros médios da qualidade da água foram: oxigênio dissolvido (3,5mg L-1), temperatura (20,1°C), pH (6,0), dureza total (18mg L-1 de CaCO3) e alcalinidade total (9mg L-1 de CaCO3). A ordem decrescente de persistência dos herbicidas na água foi Clomazone = Quinclorac > Propanil > Metsulfuron-methyl, com média de 31, 31, 10 e 7 dias, respectivamente. Os resultados indicaram que os herbicidas provocaram poucas alterações na densidade de organismos dos grupos Rotifera e Copepoda (Adulto e Nauplio). A densidade do grupo Cladocera permaneceu baixa para todo o período experimental.

In the rice paddy field it is used a large amount of agrochemical that, depending on their field persistence and toxicity, can contaminate water bodies and may affect living organism. With the objective of determining the effect of field concentrations of Clomazone, Quinclorac, Metsulfuron-methyl and Propanil herbicides on zooplankton community (Cladocers, Copepods and Rotifers), it was carried an experiment in aquaculture ponds, during March to May 2005, in autumn season. In the 1st, 2nd, 3rd, 7th, 10th, 18th, 31th and 51th days after the herbicides application, water samples were collected to evaluate the physical chemical water parameters, herbicides concentration and zooplankton community. The water physical chemical parameters means were: dissolved oxygen (3.5mg L-1), temperature (20.1°C), pH (6.0), total hardness (18mg L-1 CaCO3) and total alkalinity (9mg L-1 CaCO3). The decreasing of herbicides persistence in water was: Clomazone = Quinclorac > Propanil > Metsulfuron-methyl with average of 31, 31, 10 and 7 days, respectively. The results indicated that the herbicides provoke little alteration in density of Rotifers and, Copepods (Adults and Nauplii). The Cladocers group density remained low for the whole experiment period.

RESUMO

Em lavoura de arroz irrigado, é utilizada uma grande quantidade de agroquímicos que, dependendo da sua persistência a campo e toxicidade, podem contaminar corpos d'água e afetar organismos vivos. Com o objetivo de determinar o efeito de concentrações de campo dos herbicidas Clomazone, Quinclorac, Metsulfuron-methyl e Propanil na comunidade zooplanctônica (Cladocera, Copepoda e Rotifera), conduziu-se um experimento em viveiros de aqüicultura, de março a maio de 2005, na estação do outono. Nos dias 1º, 2º, 3º, 7º, 10º, 18º, 31º e 51º após a aplicação dos herbicidas, foram coletadas amostras de água para se determinarem parâmetros físico-químicos da água, concentração dos herbicidas e comunidade zooplanctônica. Os parâmetros médios da qualidade da água foram: oxigênio dissolvido (3,5mg L-1), temperatura (20,1ºC), pH (6,0), dureza total (18mg L-1 de CaCO3) e alcalinidade total (9mg L-1 de CaCO3). A ordem decrescente de persistência dos herbicidas na água foi Clomazone = Quinclorac > Propanil > Metsulfuron-methyl, com média de 31, 31, 10 e 7 dias, respectivamente. Os resultados indicaram que os herbicidas provocaram poucas alterações na densidade de organismos dos grupos Rotifera e Copepoda (Adulto e Nauplio). A densidade do grupo Cladocera permaneceu baixa para todo o período experimental.(AU)

In the rice paddy field it is used a large amount of agrochemical that, depending on their field persistence and toxicity, can contaminate water bodies and may affect living organism. With the objective of determining the effect of field concentrations of Clomazone, Quinclorac, Metsulfuron-methyl and Propanil herbicides on zooplankton community (Cladocers, Copepods and Rotifers), it was carried an experiment in aquaculture ponds, during March to May 2005, in autumn season. In the 1st, 2nd, 3rd, 7th, 10th, 18th, 31th and 51th days after the herbicides application, water samples were collected to evaluate the physical chemical water parameters, herbicides concentration and zooplankton community. The water physical chemical parameters means were: dissolved oxygen (3.5mg L-1), temperature (20.1ºC), pH (6.0), total hardness (18mg L-1 CaCO3) and total alkalinity (9mg L-1 CaCO3). The decreasing of herbicides persistence in water was: Clomazone = Quinclorac > Propanil > Metsulfuron-methyl with average of 31, 31, 10 and 7 days, respectively. The results indicated that the herbicides provoke little alteration in density of Rotifers and, Copepods (Adults and Nauplii). The Cladocers group density remained low for the whole experiment period.(AU)

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Cultivares transgênicas de várias culturas estão sendo utilizadas em escala comercial em muitos países. A área dedicada ao cultivo com plantas transgênicas resistentes às pragas em todo o mundo alcançou 13 milhões de hectares em 2001. As cultivares transgênicas proporcionam benefícios, mas também apresentam riscos potenciais. As avaliações do seu impacto no ambiente são conduzidas antes da sua aprovação para uso comercial, como requerido pelas normas de biossegurança. Nesta revisão, serão discutidas as conseqüências ecológicas potenciais do uso comercial na agricultura de cultivares geneticamente modificadas que apresentam resistência aos insetos-pragas. Também serão discutidos os impactos ambientais causados pelas mudanças nas práticas agrícolas, identificando-se falhas e oportunidades de pesquisa, considerando-se essa nova ferramenta tecnológica. Os comentários e análises serão baseados no conhecimento atual que se tem dos riscos e beneficios do uso de cultivares resistentes a insetos, geneticamente modificadas, dentro do contexto dos programas de manejo integrado de pragas tradicionais.

Transgenic crops are currently being cultivated on a commercial scale in many countries. The area devoted to transgenic pest resistant varieties worldwide reached 13 million hectares in 2001. These varieties offer valuable benefits but also pose potential risks. Assessments of their impact on the environment are conducted before they are approved for commercial use, as required by the regulatory biosafety frameworks. In this review, we discuss the potential ecological consequences of the commercial use in agriculture of genetically modified insect resistant crops. We also discuss the impacts caused by the change in agricultural practices, and attempt to identify gaps and possible opportunities for research, considering this new technological tool. We based our analysis and comments on the current knowledge of the risks and benefits of these genetically modified insect resistant crops, within the context of traditional insect management strategies.