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The Enemy Release Hypothesis (ERH) has been a factor influencing the establishment of some exotic species worldwide. We tested if the ERH could be influencing populations of the exotic predator Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae) in Brazil. During two years, three local predatory coccinellid species and Harmonia axyridis were sampled in Brassica oleracea in six organic farms in the midwest of the country. Parasitoids were detected by rearing (emerged) and qPCR Melting Curve Analysis (unemerged). Host density-dependence and spillovers were used to evaluate coccinellid population effects of parasitism. Six parasitoid species were found, including two new records for Brazil. Although Harmonia axyridis harbored fewer parasitoid species, parasitism was not lower and parasitoid density-dependence was not weaker on it compared to the local species. Spillovers among hosts occurred both onto Harmonia axyridis and from it. The ERH was rejected for these parasitoids and, therefore, it did not contribute to the invasiveness of Harmonia axyridis in Brazil.

Background Animal pollination is an important ecosystem function and service, ensuring both the integrity of natural systems and human well-being. Although many knowledge shortfalls remain, some high-quality data sets on biological interactions are now available. The development and adoption of standards for biodiversity data and metadata has promoted great advances in biological data sharing and aggregation, supporting large-scale studies and science-based public policies. However, these standards are currently not suitable to fully support interaction data sharing. Results Here we present a vocabulary of terms and a data model for sharing plant–pollinator interactions data based on the Darwin Core standard. The vocabulary introduces 48 new terms targeting several aspects of plant–pollinator interactions and can be used to capture information from different approaches and scales. Additionally, we provide solutions for data serialization using RDF, XML, and DwC-Archives and recommendations of existing controlled vocabularies for some of the terms. Our contribution supports open access to standardized data on plant–pollinator interactions. Conclusions The adoption of the vocabulary would facilitate data sharing to support studies ranging from the spatial and temporal distribution of interactions to the taxonomic, phenological, functional, and phylogenetic aspects of plant–pollinator interactions. We expect to fill data and knowledge gaps, thus further enabling scientific research on the ecology and evolution of plant–pollinator communities, biodiversity conservation, ecosystem services, and the development of public policies. The proposed data model is flexible and can be adapted for sharing other types of interactions data by developing discipline-specific vocabularies of terms.

Invasive species can reach high abundances and dominate native environments. One of the most impressive examples of ecological invasions is the spread of the African subspecies of the honey bee throughout the Americas, starting from its introduction in a single locality in Brazil. The invasive honey bee is expected to more negatively impact bee community abundance and diversity than native dominant species, but this has not been tested previously. We developed a comprehensive and systematic bee sampling scheme, using a protocol deploying 11,520 pan traps across regions and crops for three years in Brazil. We found that invasive honey bees are now the single most dominant bee species. Such dominance has not only negative consequences for abundance and species richness of native bees but also for overall bee abundance (i.e., strong “numerical” effects of honey bees). Contrary to expectations, honey bees did not have stronger negative impacts than other native bees achieving similar levels of dominance (i.e., lack of negative “identity” effects of honey bees). These effects were markedly consistent across crop species, seasons and years, and were independent from land-use effects. Dominance could be a proxy of bee community degradation and more generally of the severity of ecological invasions.

Environmental risk assessments (ERAs) are required before utilizing exotic arthropods for biological control (BC). Present ERAs focus on exposure analysis (host/prey range) and have resulted in approval of many specialist exotic biological control agents (BCA). In comparison to specialists, generalist arthropod BCAs (GABCAs) have been considered inherently risky and less used in classical biological control. To safely consider exotic GABCAs, an ERA must include methods for the analysis of potential effects. A panel of 47 experts from 14 countries discussed, in six online forums over 12 months, scientific criteria for an ERA for exotic GABCAs. Using four case studies, a three-tiered ERA comprising Scoping, Screening and Definitive Assessments was developed. The ERA is primarily based on expert consultation, with decision processes in each tier that lead to the approval of the petition or the subsequent tier. In the Scoping Assessment, likelihood of establishment (for augmentative BC), and potential effect(s) are qualitatively assessed. If risks are identified, the Screening Assessment is conducted, in which 19 categories of effects (adverse and beneficial) are quantified. If a risk exceeds the proposed risk threshold in any of these categories, the analysis moves to the Definitive Assessment to identify potential non-target species in the respective category(ies). When at least one potential non-target species is at significant risk, long-term and indirect ecosystem risks must be quantified with actual data or the petition for release can be dismissed or withdrawn. The proposed ERA should contribute to the development of safe pathways for the use of low risk GABCAs.

Due to typesetting errors, Table 5 was not displayed correctly in the initial online publication. The original online article has been corrected.

The objective of this work was to determine the survival pattern of the cotton boll weevil during fallow in Midwestern Brazil. The percentage of adults that remained in the cotton reproductive structures, the percentage of adults searching for shelters, and the longevity of adults fed on pollen and nectar as alternative food sources were determined. For this, four populations were sampled in cotton squares and bolls, totaling 11,293 structures, from 2008 to 2012. The emergency of cotton weevil adults was monitored from the collection of the structures until the next cotton season. In the laboratory, newly-emerged adults were fed on hibiscus or Spanish needle, and their life span was monitored individually. Most adults (85.73%) left the reproductive structures, regardless of the cotton plant phenology, up to 49 days after the structures were collected. One individual (0.0002%) from 5,544 adults was found alive after the fallow period. The diet with hibiscus and Spanish needle provided adult longevity of 76±38 days, which was enough time for adults to survive during the fallow period. Most of the boll weevils leave the cotton structures at the end of harvest, survive using alternative food sources, and do not use cotton plant structures as shelter during the legal cotton fallow period in Midwestern Brazil. Resumo: O objetivo deste trabalho foi determinar o padrão de sobrevivência do bicudo-do-algodoeiro durante o pousio no Centro-Oeste do Brasil. Foram determinadas as percentagens de adultos das populações que permaneceram nas estruturas reprodutivas do algodoeiro, as percentagens de adultos que saíram para os refúgios, e a longevidade dos adultos alimentados com pólen e néctar como fontes de alimentos alternativos. Para tanto, foram amostradas quatro populações em botões florais e maçãs do algodoeiro, que totalizam 11.293 estruturas, de 2008 a 2012. A emergência de adultos do bicudo-do-algodoeiro foi monitorada desde a coleta das estruturas até a próxima safra de algodão. Em laboratório, adultos recém-emergidos foram alimentados com hibisco ou picão, e sua longevidade foi monitorada individualmente. A maioria dos adultos (85,73%) saiu das estruturas reprodutivas, independentemente da fenologia do algodoeiro, até 49 dias após as estruturas terem sido coletadas. Um indivíduo (0.0002%) entre 5.544 adultos foi encontrado vivo após o período da entressafra. A dieta de hibisco e picão permitiu uma longevidade de 76±38 dias, tempo suficiente para manter os adultos vivos durante a entressafra. A maioria dos bicudos-de-algodoeiro deixa as estruturas reprodutivas do algodoeiro no final da colheita, sobrevive com alimento alternativo e não usa as estruturas da planta como abrigo durante o período legal de pousio na Região Centro-Oeste do Brasil.

Dose-response assays and surrogate species are standard methods for risk analysis for environmental chemicals. These assume that individuals within a species have unimodal responses and that a surrogate species can predict responses of other related taxa. We exposed immature individuals of closely related aphidophagous coccinellid predators, Cycloneda sanguinea and Harmonia axyridis, to Cry1Ac and Cry1F toxins through uniform and constant artificial tritrophic exposure through Myzus persicae aphids. Both toxins were detected in coccinellid pupae, with individual and interspecific variation. Uptake was significantly higher in H. axyridis than in C. sanguinea, both in the proportion of individuals and the concentrations per individual. We also observed bimodal uptake of the Cry toxins by H. axyridis, which indicated that some individuals had low bioaccumulation and some had high bioaccumulation. This suggests that standard dose-response assays need to be interpreted with caution and future assays should examine the modality of the responses. In addition, the similarity in the biological effects of the Cry toxins in the two predators was due to different biological exposure mechanisms. The majority of H. axyridis were exposed both internally and in the gut, while C. sanguinea was exposed primarily in the gut. Thus, despite their close phylogenetic relatedness, these species would not be good surrogates for each other and the surrogate species methodology should be tested more rigorously.

Although the importance of bees as the pollinators responsible for maintaining gene flow for many native and cultivated plants in ecosystems around the world is recognized, much of their biodiversity and behavior remains to be discovered. Stingless bees are considered key pollinators for several plant species in tropical and subtropical ecosystems and they also provide pollination services for economically important agricultural crops. Many countries are using the honey bee (Apis mellifera Linnaeus, 1758, Hymenoptera: Apidae) as a surrogate to evaluate the risk of pesticides to all species of bees. However, there is uncertainty regarding the extent to which honey bees can serve as surrogates for non-Apis bee species in the risk assessment for pesticides. This paper provides a short overview of the life history traits relevant in risk assessment of stingless bees. It summarizes what is known about stingless bee exposure to pesticides compared to that of honey bees and presents criteria for potential candidate species from Brazil for use in pesticide risk assessment in tropical environments. This paper also identifies gaps in knowledge of bee biology and pesticide exposure routes not covered by the current honey bee exposure assessment paradigm. Based on these gaps, research is needed on life history traits, estimates of nectar and pollen consumption, mud, resin, and water collection and available protocols to adequately assess toxic effects of pesticides to stingless bees. This review is part of a series of papers on the risk of exposure of non-Apis bees to pesticides.

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International audience; DNA methods are useful to identify ingested prey items from the gut of predators, but reliable detection is hampered by low amounts of degraded DNA. PCR-based methods can retrieve minute amounts of starting material but suffer from amplification biases and cross-reactions with the predator and related species genomes. Here, we use PCR-free direct shotgun sequencing of total DNA isolated from the gut of the harlequin ladybird Harmonia axyridis at five time points after feeding on a single pea aphid Acyrthosiphon pisum. Sequence reads were matched to three reference databases: Insecta mitogenomes of 587 species, including H. axyridis sequenced here; A. pisum nuclear genome scaffolds; and scaffolds and complete genomes of 13 potential bacterial symbionts. Immediately after feeding , multicopy mtDNA of A. pisum was detected in tens of reads, while hundreds of matches to nuclear scaffolds were detected. Aphid nuclear DNA and mtDNA decayed at similar rates (0.281 and 0.11 h À1 respectively), and the detectability periods were 32.7 and 23.1 h. Metagenomic sequencing also revealed thousands of reads of the obligate Buchnera aphidicola and facultative Regiella insecticola aphid symbionts, which showed exponential decay rates significantly faster than aphid DNA (0.694 and 0.80 h À1 , respectively). However, the facultative aphid symbionts Hamil-tonella defensa, Arsenophonus spp. and Serratia symbiotica showed an unexpected temporary increase in population size by 1–2 orders of magnitude in the predator guts before declining. Metagenomics is a powerful tool that can reveal complex relationships and the dynamics of interactions among predators, prey and their symbionts.

We studied the influence of synthetic (E)-2-hexenal on the abundance of Telenominae aiming to attract parasitoids and enhance stink bug egg parasitism in treated areas. We conducted experiments in 2006, 2007 and 2008 soybean seasons with two short-term (one week) and one long-term (seven weeks) experiment, respectively. We evaluated the abundance of parasitoids with yellow sticky traps and estimated the incidence and intensity of parasitism with sentinel eggs of Euschistus heros Fabricius (Hemiptera: Pentatomidae) or with tulle bags, enclosing laboratory pregnant E. heros as an egg source. In short-term experiments, there was increased abundance of Trissolcus spp. (Hymenoptera: Platygastridae: Telenominae) in treated areas, associated with greater intensity of parasitism. In long-term experiments, treatment with (E)-2-hexenal did not influence the abundance of Telenominae or parasitism levels, but increased egg predation. Applications of (E)-2-hexenal can be used to increase recruitment of Trissolcus spp. in the early flowering stages of soybean and also to attract other natural enemies, but do not increase egg parasitism.

This study aimed to evaluate the importance of wild bee and feral honeybee visits for cotton production on conventional and organic farms. Experiments were conducted in Brazil, on a conventional cotton farm in Mato Grosso state in the Amazon biome and on an organic farm in Paraíba state in the Caatinga biome. On the conventional farm, bee assemblage and cotton production were measured near to and far from natural vegetation. Bee richness, fibre fraction, seed number and yield (Kg/ha) were higher by 57.14, 1.95, 17.77 and 18.44% respectively in plots near natural vegetation, but bee abundance did not vary with distance to natural vegetation. On the organic farm, because the cropping area is surrounded by natural vegetation, pollination deficit was evaluated using an exclusion experiment where cotton production of flowers bagged to prevent bee visitation (spontaneous self-pollination) was compared to production of flowers open to bee visitation (open pollination). Open pollinated flowers had higher average boll weight, fibre weight and seed number. Although cotton is not directly dependent on bee pollination, bees increased cotton production on the organic farm by more than 12% for fibre weight and over 17% for seed number. Our data confirm the importance of maintaining communities of pollinators on cotton farms, especially for organic production.

The integration of agroforestry plots with ephemeral crops such as vegetables on the farm scale can probably serve as a refuge and source of beneficial insects. Therefore, agroforestry systems possibly represent an alternative that favors ecosystem services and help growers in the transition process from conventional to agro-ecological agriculture. This study aimed to understand the role of introducing agroforestry systems in structuring insect communities, with consequences for the abundance of herbivore and natural enemies, contributing to farm management and favoring biological control as an ecosystem service. Field surveys showed that agroforestry systems can harbor more species than horticultural crops, independent of the functional group. They also contain a greater diversity of herbivores and an even greater diversity profile of natural enemy communities. Agroforestry systems served as a source of natural enemies that can colonize horticultural crops when herbivores are present. As a consequence, natural enemies can establish a numerical response to herbivore abundance, but their communities are also affected by stochastic factors related to climatic conditions. Thus, agroforestry systems and agro-ecological practices might favor an agriculture based on the maintenance and conservation of ecosystem services.

Insect predators are exposed to the Cry1Ac toxin in Bt cotton fields through several pathways. In this study, we investigated the effects of activated Cry1Ac added to a diet on Cycloneda sanguinea (L.) (Coleoptera: Coccinellidae), which is one of the main predators of non-target pests in Brazilian cotton. Direct bitrophic exposure of C. sanguinea to Cry1Ac was done by feeding beetles with Aphis gossypii (Glover) (Hemiptera: Aphidae) sprayed with 500 μg per ml Cry1Ac solution. Larval and pupal survival, development time, aphid consumption, and adult longevity were recorded daily. Couples within the same experimental treatment were paired and numbers of eggs laid and hatched per female were recorded daily. Net replacement rate was calculated for each female. During development, a C. sanguinea larva consumed on average 1.8 μg of activated Cry1Ac. No significant differences due to Cry1Ac were observed for any of the response variables, except aphid consumption. Larvae receiving Cry1Ac consumed more aphids than larvae receiving distilled water alone. Additional statistical analyses were conducted to evaluate independence of responses, and for the independent responses, a simple meta-analysis was conducted to test the null hypothesis that all responses were zero. Nearly all of the response variables were statistically independent. Two pairs of responses were not independent, but the associated multivariate tests were not significant. The meta-analysis suggested that all effects were not different from random variation around zero and no cumulative effects could be detected. Our results indicated that bitrophic exposure to activated Cry1Ac is likely to have little or no adverse ecological effect on C. sanguinea.

Ten pollinator policies1. Raise pesticide regulatory standards.2. Promote integrated pest management (IPM).3. Include indirect and sublethal ef ects inGM crop risk assessments.4. Regulate movement of managed pollinators.5. Develop incentives, such as insurance schemes,to help farmers benef t from ecosystemservices instead of agrochemicals.6. Recognize pollination as an agricultural inputin extension services.7. Support diversif ed farming systems.8. Conserve and restore ?green infrastructure?(a network of habitats that pollinators can movebetween) in agricultural and urban landscapes.9. Develop long-term monitoring of pollinatorsand pollination.10. Fund participatory research on improvingyields in organic, diversif ed, and ecologicallyintensif ed farming. Fil: Dicks, Lynn V.. University of East Anglia; Reino Unido Fil: Viana, Blandina. Universidade Federal da Bahia; Brasil Fil: Bommarco, Riccardo. Swedish University of Agricultural Sciences; Suecia Fil: Brosi, Berry. Emory University; Estados Unidos Fil: del Coro Arizmendi, María. Universidad Nacional Autónoma de México; México Fil: Cunningham, Saul A.. The Australian National University; Australia Fil: Galetto, Leonardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentina. Universidad Nacional de Córdoba; Argentina Fil: Hill, Rosemary. James Cook University. Commonwealth Scientific and Industrial Research Organisation Land and Water; Australia Fil: Lopez, Ariadna V.. Universidade Federal de Pernambuco; Brasil Fil: Pires, Carmen. Embrapa Recursos Genéticos e Biotecnologia; Brasil Fil: Taki, Hisatomo. Forestry and Forest Products Research Institute; Japón Fil: Potts, Simon G.. University of Reading; Reino Unido

International audience; AbstractIn Brazil, where the use of neonicotinoids is allowed in bee-attracting flowering crops, we investigated whether thiamethoxam intake during the larval stage of the native bee species Scaptotrigona aff. depilis affects the survival and development by exposing larvae to contaminated food. Our results indicated that the larvae exposed to the dose at a field-realistic level and to the doses ranging around it had their survival rates significantly impaired. At the highest doses, we observed larvae and pupae with shorter and longer development times, respectively, and the formation of smaller and asymmetric specimens. Evidently, we need to consider that thiamethoxam reaches the pollen and nectar at residual levels, and that they are processed by nurse bees before destined for offspring. Nevertheless, our findings suggest a warning, since the individuals had their biological parameters affected by thiamethoxam, when exposed to doses at field-realistic levels.

International audience; Characterizing trophic networks is fundamental to many questions in ecology, but this typically requires painstaking efforts, especially to identify the diet of small generalist predators. Several attempts have been devoted to develop suitable molecular tools to determine predatory trophic interactions through gut content analysis, and the challenge has been to achieve simultaneously high taxonomic breadth and resolution. General and practical methods are still needed, preferably independent of PCR amplification of barcodes, to recover a broader range of interactions. Here we applied shotgun-sequencing of the DNA from arthro-pod predator gut contents, extracted from four common coccinellid and dermapteran predators co-occurring in an agroecosystem in Brazil. By matching unassembled reads against six DNA reference databases obtained from public databases and newly assembled mito-genomes, and filtering for high overlap length and identity, we identified prey and other foreign DNA in the predator guts. Good taxonomic breadth and resolution was achieved (93% of prey identified to species or genus), but with low recovery of matching reads. Two to nine trophic interactions were found for these predators, some of which were only inferred by the presence of parasitoids and components of the microbiome known to be associated with aphid prey. Intraguild predation was also found, including among closely related ladybird species. Uncertainty arises from the lack of comprehensive reference databases and reliance on low numbers of matching reads accentuating the risk of false positives. We discuss caveats and some future prospects that could improve the use of direct DNA shotgun-sequencing to characterize arthropod trophic networks.

Resumo: Nas últimas décadas, o declínio de populações de abelhas silvestres e o colapso de colônias de Apis mellifera têm preocupado pesquisadores e apicultores. O objetivo deste artigo de revisão foi compilar alguns dos estudos mais relevantes relacionados às possíveis causas desses problemas - como nutrição, manejo, patógenos, parasitas e efeitos de agrotóxicos -, além de apresentar um breve histórico da síndrome "colony collapse disorder" (CCD) nos Estados Unidos e na Europa. Abordaram-se com mais detalhes os estudos desenvolvidos no Brasil, principalmente sobre agrotóxicos utilizados na agricultura e patógenos e parasitas que acometem as colônias de A. mellifera africanizada. Casos de enfraquecimento, declínio e colapso têm sido registrados, principalmente nos estados de São Paulo e Santa Catarina, que somam grandes perdas. Resultados das ocorrências analisadas indicaram que as mortalidades em massa registradas no Brasil não estavam associadas a patógenos ou a parasitas. Somente dois casos com características semelhantes às descritas para CCD foram registrados, porém sem causas definidas. Para que se conheçam as causas de enfraquecimentos e perdas de colônias de abelhas, é urgente a implementação de programas oficiais de levantamento sistemático da sanidade apícola, associados a pesquisas com foco nas avaliações dos possíveis impactos da fragmentação de habitats e das práticas agrícolas sobre as comunidades de abelhas. Abstract: In the last decades, the decline of wild bee populations and the collapse of Apis mellifera colonies have concerned researchers and beekeepers. The objective of this review was to compile some of the most relevant studies related to the possible causes of these problems - such as nutrition, management, pathogens, parasites, and the effects of pesticides -, besides presenting a brief history of the colony collapse disorder syndrome (CCD) in the United States and Europe. The studies developed in Brazil were presented in more detail, mainly those on pesticides used in agriculture and on pathogens and parasites that attack the colonies of Africanized A. mellifera. Cases of weakening, decline, and collapse have been recorded in Brazil, mainly in the states of São Paulo and Santa Catarina, which add up to great losses. Results of the analyzed occurrences indicated that the recorded mass mortalities were not associated with pathogens or parasites. Only two cases with characteristics similar to those described for CCD were recorded, but without defined causes. In order to know the causes of the weakening and collapses of colonies, the implementation of official programs is urgent for the systematic survey of bee health, associated with research focusing on assessments of possible impacts of habitat fragmentation and agricultural practices on bee communities.

Fil: Garibaldi, Lucas Alejandro. Universidad Nacional de Río Negro. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Garibaldi, Lucas Alejandro. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Investigaciones en Recursos Naturales, Agroecología y Desarrollo Rural; Argentina. Fil: Carvalheiro, Luísa G. Universidade de Brasília. Campus Universitário Darcy Ribeiro. Departamento de Ecologia; Brasil. Fil: Carvalheiro, Luísa G. Universidade de Lisboa. Faculdade de Ciências. Centre for Ecology, Evolution and Environmental Changes (CE3C); Portugal. Fil: Carvalheiro, Luísa G. Naturalis Biodiversity Center; Países Bajos. Fil: Vaissière, Bernard E. Institut national de la recherche agronomique; Francia. Fil: Gemmill Herren, Barbara. Food and Agriculture Organization of the United Nations; Italia. Fil: Hipólito, Juliana. Universidade Federal da Bahia. Campus de Ondina. Departamento de Zoologia. Instituto de Biologia; Brasil. Fil: Freitas, Breno M. Universidade Federal do Ceará. Campus Universitário do Pici. Departamento de Zootecnia. Centro de Ciências Agrárias; Brasil. Fil: Ngo, Hien T. Intergovernmental Platform on Biodiversity and Ecosystem Services (IPBES). UN Campus. IPBES Secretaria; Alemania. Fil: Azzu, Nadine. Food and Agriculture Organization of the United Nations; Italia. Fil: Sáez, Agustín. Universidad Nacional del Comahue. Instituto de Investigaciones en Biodiversidad y Medioambiente. Laboratorio Ecotono; Argentina. Fil: Sáez, Agustín. Consejo Nacional de Investigaciones Científicas y Técnica. Instituto de Investigaciones en Biodiversidad y Medioambiente. Laboratorio Ecotono; Argentina. Fil: Åström, Jens. Norwegian Institute for Nature Research; Noruega. Fil: An, Jiandong. Chinese Academy of Agricultural Sciences. Institute of Apicultural Research. Key Laboratory for Insect-Pollinator Biology of the Ministry of Agriculture; China. Fil: Blochtein, Betina. Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS); Brasil. Fil: Buchori, Damayanti. Bogor Agricultural University. Faculty of Agriculture. Department of Plant Protection; Indonesia. Fil: Chamorro García, Fermín J. Universidad Nacional de Colombia. Departamento de Biología. Laboratorio investigaciones en Abejas (LABUN); Colombia. Fil: Oliveira da Silva, Fabiana. Universidade Federal de Sergipe. Campus do Sertão. Departamento de Educação em Ciências Agrárias e da Terra; Brasil. Fil: Devkota, Kedar. Institute of Agriculture and Animal Science; Nepal. Fil: de Fátima Ribeiro, Márcia. Embrapa Semiárido; Brasil. Fil: Freitas, Leandro. Jardim Botânico do Rio de Janeiro (JBRJ); Brasil. Fil: Gaglianone, Maria C. Universidade Estadual do Norte Fluminense Darcy Ribeiro. Laboratório de Ciências Ambientais; Brasil. Fil: Goss, Maria. University of Zimbabwe. Faculty of Agriculture. Crop Science Department; Zimbabue. Fil: Irshad, Mohammad. National Agricultural Research Centre. Honey Bee Research Institute. Conservation and Management of Pollinators for Sustainable Agriculture through Ecosystem Approach project; Pakistán. Fil: Kasina, Muo. Kenya Agricultural and Livestock Research Organisation-Sericulture; Kenia. Fil: Pacheco Filho, Alípio J. Universidade Federal do Ceará. Campus Universitário do Pici. Departamento de Zootecnia. Centro de Ciências Agrárias; Brasil. Fil: Piedade Kiill, Lucia H. Embrapa Semiárido; Brasil. Fil: Kwapong, Peter. University of Cape Coast. School of Biological Sciences. College of Agriculture and Natural Sciences; Ghana. Fil: Nates Parra, Guiomar. Universidad Nacional de Colombia. Departamento de Biología. Laboratorio investigaciones en Abejas (LABUN); Colombia. Fil: Pires, Carmen. Parque Estação Biológica. Embrapa Recursos Genéticos e Biotecnologia; Brasil. Fil: Pires, Viviane. Instituto do Meio Ambiente e Recursos Hídricos (INEMA)–UR Extremo Sul; Brasil. Fil: Rawal, Ranbeer S. Pant Institute of Himalayan Environment and Development; India. Fil: Rizali, Akhmad. University of Brawijaya. Faculty of Agriculture. Department of Plant Pest Diseases; Indonesia. Fil: Saraiva, Antonio M. Universidade de São Paulo. Escola Politécnica; Brasil. Fil: Veldtman, Ruan. Kirstenbosch Research Centre. South African National Biodiversity Institute; Sudáfrica. Fil: Veldtman, Ruan. Stellenbosch University. Conservation Ecology and Entomology; Sudáfrica. Fil: Viana, Blandina F. Universidade Federal da Bahia. Campus de Ondina. Departamento de Zoologia. Instituto de Biologia; Brasil. Fil: Witter, Sidia. Fundação Estadual de Pesquisa Agropecuária (Fepagro Vale do Taquari). Centro de Pesquisa Emílio Schenk; Brasil. Fil: Zhang, Hong. Chinese Academy of Agricultural Sciences. Institute of Apicultural Research. Key Laboratory for Insect-Pollinator Biology of the Ministry of Agriculture; China. Ecological intensification, or the improvement of crop yield through enhancement of biodiversity, may be a sustainable pathway toward greater food supplies. Such sustainable increases may be especially important for the 2 billion people reliant on small farms, many of which are undernourished, yet we know little about the efficacy of this approach. Using a coordinated protocol across regions and crops, we quantify to what degree enhancing pollinator density and richness can improve yields on 344 fields from 33 pollinator-dependent crop systems in small and large farms from Africa, Asia, and Latin America. For fields less than 2 hectares, we found that yield gaps could be closed by a median of 24% through higher flower-visitor density. For larger fields, such benefits only occurred at high flower-visitor richness. Worldwide, our study demonstrates that ecological intensification can create synchronous biodiversity and yield outcomes.

International audience; Stingless bees, particularly Trigona spinipes, are important pollinators in tropical ecosystems and are potentially affected by environmental contaminants. In this study, we tested the possible negative effects on T. spinipes larvae of the ingestion of a diet contaminated with Cry1Ac Bt-toxin. This toxin is expressed in genetically modified cotton plants. A method of rearing stingless bee larvae is described in this paper. The larvae were provided with either pure larval diet, diluted larval diet, or larval diet diluted in a Cry1Ac solution compatible with the lethal pest-exposure level (50 μg/mL). Cry1Ac ingestion did not impair the development of worker larvae, but the diluted diet slightly increased larval mortality. These results indicate that harmful effects on stingless bee larvae due to the ingestion of pollen-expressed Cry1Ac toxin are unlikely under field conditions.

We evaluated an artificial tritrophic exposure system for use in ecotoxicological evaluations of environmental stressors on aphidophagous predators. It consists of an acrylic tube with a Parafilm M sachet containing liquid aphid diet, into which can be added environmental stressors. Immature Cycloneda sanguinea, Harmonia axyridis and Chrysoperla externa, and adult H. axyridis were reared on Myzus persicae. Larval and pupal development and survival of all species and reproductive parameters of H. axyridis were similar to published results. The system provides a suitable tritrophic exposure route, enables ex-ante evaluation of stressors, and improves the accuracy of the assessment.

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Herbivory is known to increase the emission of volatiles, which attract natural enemies to herbivore-damaged plants in laboratory and agricultural systems. We report on signalling through volatiles induced by Euschistus heros (F.) (Heteroptera: Pentatomidae) in two legumes that influence the attraction and retention of the egg parasitoid Telenomus podisi (Ashmead) (Hymenoptera: Scelionidae). Air-borne extracts obtained from two host plants of E. heros, soybean, Glycine max, and pigeon pea, Cajanus cajan (Leguminosae), produce a different blend of emitted volatiles when attacked by adult males or females and nymphs of the pest species, compared with the undamaged plants. The same results were obtained when the plants were treated with extracted saliva of E. heros which had been mechanically introduced into the plants. This indicates that some substance in the saliva contributed to the release of the volatiles. Bioassays in a Y-tube olfactometer with female T. podisi and treated plants confirmed the significant preference of the egg parasitoid for plants attacked by either males, females, or fourth instar nymphs of the pest species. On the other hand, volatile extracts obtained from soybean subjected to the velvetbean caterpillar, Anticarsia gemmatalis, a non-host species for T. podisi, showed a different blend of volatiles compared to those obtained from plants subjected to E. heros. Additionally, the volatiles obtained from this plant–host complex were not attractive to T. podisi. These results indicate that E. heros causes an increase in the emission of specific plant volatiles, and that the induction is possibly caused by an elicitor present in the pest saliva. The possibility that these plant volatiles play an important role in the attraction and retention of the egg parasitoid T. podisi is discussed.

We found that variation in temperature and humidity significantly affected mortality rates and population dynamics of the spittlebug Deois flavopicta Still by monitoring cohorts of diapausing eggs and nymphs for three generations. Cohorts of quiescent eggs, when exposed to increasing periods of high moisture (free water), produced higher proportions of eggs resuming embryonic development in laboratory experiments. The accumulated number of eggs resuming development as a function of days of exposure to moist conditions was modeled using a β distribution. Periods of drought and high temperatures after the beginning of postdiapause development increased embryonic and nymphal mortality. Mortality was modeled with a linear function, and in combination with the development model allowed the simulation of varying mortality rates in the newly emerged nymphal population. Comparisons with field data demonstrated a close fit to the observed and expected proportion of nymphs hatching daily. By accurately simulating natural mortality, hatching distribution and population dynamics, the model promises to be useful for managing the spittlebug in the field.

Eleven species of native or naturalized grasses were found hosting spittlebug nymphs in the natural grassland areas around Brasília in the Fe-deral District of Brazil. A large number of nymphs were found on the species Axonopus marginatus (Trin.) Chase. Out of a total of 224 observed nymphs, 85.7% were found feeding on A. marginatus. Apparently the presence of the spittlebug nymphs in the cerrado vegetation, the Brazilian savanna, was associated with any form of disturbance, such as cattle grazing and partial deforestation. Nymphs were found only in disturbed areas of the "cerrado campo sujo" and in the cerrado sensu strictu. The densities of spittlebug nymphs in the cerrado were lower than the density found in the cultivated pasture. The nymphal density in the cerrado sensu strictu was approximately 105 times lower than the densities in Brachiaria ruziziensis Germain & Evrard area. In two sites of "campo sujo" form of cerrado the densities were, approximately, 2,273 and 1,212 times lower than the densities in B. ruziziensis areas. The distribution and density of the spittlebug in the natural vegetation were influenced by the presence of adjacent infested areas of cultivated pasture. This fact indicates that areas of Brachiaria are the source of infestation for other host plants. Onze espécies de gramíneas nativas ou naturalizadas foram encontradas hospedando ninfas da cigarrinha-das-pastagens em áreas de cerrado na região de Brasília, Distrito Federal. Grande número de ninfas foi encontrado na espécie Axonopus marginatus (Trin.) Chase. Do total de 224 ninfas observadas, 85,7% foram encontradas alimentando-se nessa espécie de gramínea. Aparentemente a presença da cigarrinha-das-pastagens nas gramíneas do cerrado estava associada com qualquer forma de perturbação, tais como pastejo pelo gado ou desmatamento parcial. Ninfas foram encontradas somente em áreas perturbadas de cerrado do tipo campo sujo e sensu strictu. As densidades de ninfas no cerrado foram muito mais baixas do que as densidades encontradas em pastagens cultivadas. O número de ninfas/m² no cerrado sensu strictu foi aproximadamente 105 vezes mais baixo do que as densidades encontradas nas áreas de Brachiaria ruziziensis Germain & Evrard . Em dois sítios de cerrado do tipo campo sujo as densidades foram, aproximadamente, 2.273 e 1.212 vezes mais baixas do que as densidades nas áreas de B. ruziziensis. A distribuição e as densidades populacionais da cigarrinha-das-pastagens em áreas de vegetação natural foram influenciadas pela presença de pastagens cultivadas infestadas por este inseto nas adjacências, sugerindo que áreas de Brachiaria são focos de infestação para outras hospedeiras.

A field-based experimental study examined the roles of temperature and moisture in the dry-season embryonic dormancy and postdormancy hatching of the spittlebug Deois flavopicta Stal from Brazil’s dry interior region. The results show that dormancy consists of two discrete parts: an initial period of diapause that persists from April to the beginning of July, followed by a period of postdiapause quiescence that prevails until the rainy season begins (usually October). Low temperatures during the early part of the diapause period accelerates diapause development, whereas contact with liquid water determines the timing of postdiapause hatching. Soil temperatures during June and July and the relative humidity of the soil during August and September strongly affect overwintering survival and thus are important in determining the size of the nymphal population after dormancy. The findings indicate that, like hibernation and aestivation in temperate-zone insects, dry-season dormancy in tropical insects is a dynamic state that is influenced by seasonal changes in key environmental factors.

We studied the movement and feeding behavior of nymphs of the grass feeding spittlebug Deois flavopicta Stal to evaluate the role of host plant species on the spatial distribution of the nymphs. The inter- and intraplant foraging patterns of the nymphs contributed to their patchy distributions. The young nymphs, despite their weak motility, moved from the hatching spot and chose feeding sites. They tend to move less when host plants were present. Plant quality near hatching sites influenced the movement pattern of newly hatched nymphs. Egg densities at the oviposition sites did not influence the movement of newly hatched nymphs. The distribution of nymphs in relation to differences in host species and shoot age of host plant was studied in the field and in multiple choice experiments. Both young and old nymphs preferred plants of the introduced host in the genus Brachiaria over the native grass Axonopus marginatus (Trinius) Chase. The nymphs fed gregariously on buds and young shoots as first and second instars and in small groups of third, fourth, and fifth instars on old shoots of different sizes. These patterns of attack may be related to differences in tissue hardness or amino acid content between young and old shoots, and between host species. Nymphal survivorship was higher on B. ruziziensis, the preferred host plant. In addition, survivorship of newly hatched nymphs was higher on young buds and shoots compared with old shoots. The possible consequences of nymphal feeding behavior on population dynamics are discussed.

Summary 1. Predictions from the Phylogenetic Constraints Hypothesis were tested for the first time in a tropical system using the pasture pest Deois flavopicta Stal, which oviposits into the ground and not into plant tissues. The prediction that there is no oviposition preference–larval performance linkage was supported. The absence of such a link provides an evolutionary basis for eruptive population dynamics. 2. The effects of host species and host plant quality on the preference of ovipositing females of D. flavopicta and performance of their offspring on the selected host plants were tested at the population level. 3. Female oviposition behaviour was affected by the presence of the host plant. Females of D. flavopicta showed a strong preference to oviposit close to host plants. The number of eggs was higher in pots containing Brachiaria ruziziensis (121.88 ± 13.70) than in pots containing only the wet oviposition substrate (5.2 ± 1.98) or dry oviposition substrate (0.067 ± 0.067). Ovipositing females did not, however, discriminate between plants of Brachiaria decumbens and Axonopus marginatus and did not show a strong oviposition preference in relation to differences in plant quality (protein and fibre content). They did show oviposition preference for plants under the high watering regime. The mean number of eggs collected from pots with non water-stressed plants was 60% higher than the mean number of eggs collected on pots with water-stressed plants. 4. Although females did not show ovipositional preference, spittlebug larval performance, measured as percentage survival and duration of nymphal period, was better on plants of high protein and low fibre content. These results indicate that there is not a linkage between female oviposition preference and subsequent nymphal performance in relation to differences in protein and fibre content in the host plants. There was, however, a limited linkage between oviposition preference and nymphal performance in relation to plant water content. Females showed preference for moist sites that have high survival of newly hatched nymphs. 5. Evidence indicates that for D. flavopicta, the influences of natality and female oviposition behaviour in response to plant quality are not the major factors driving population outbreaks, which is in accordance with the Phylogenetic Constraints Hypothesis.

We examined the effect of shoot size distribution within plants and different stage of host plant development on the pattern of attack of Andricus sp. on gambel oak, Quercus gambelli Nuttall. The gall-inducing wasp preferred large diameter shoots to small ones in 2 populations of host plant. Attack on larger shoots was significantly nonrandom and occurred even though these shoots were relatively scarce in the shoot population. Large shoots accounted for only 5.51 and 12.72% of the total shoots in an urban and forest site, respectively. The percentage of attack on shoots in the largest shoot diameter class was 10.53 and 48.74% in the urban and forest site, respectively. Gall density decreased with maturity of the host plant and was 3 times higher on juvenile plants compared with mature plants. The distribution of attack in relation to plant age was not related to changes in shoot size with the age of the plants. Gambel oak may become resistant to gall formation with increasing age. Survival was 33.72% higher on large shoots (83.72%) compared with small shoots (50.00%). Larval survival did not change with plant age among host plants. The pattern of attack in relation to shoot size suggests that Andricus sp. prefer to oviposit on large shoots in which larval performance was highest. Andricus sp. might show a flexible oviposition preference hierarchy for shoot lengths. Females attacked the longest shoots available rather than showing a fixed preference for specific shoot lengths.

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A survey of natural enemies ofSenna obtusifolia(Leguminosae: Cesalpinaceae) was made in 46 localities in Brazil. Twenty-one preselected insect species were used in a multivariate analysis in a search for potential biocontrol agents, based on frequency of occurrence of each species, degree of insect/host association, and damage level. Insect communities were organized in a binary matrix (presence/absence of the species); measures of distance and similarities were based on the Jaccard coefficient, and cluster analysis was then conducted. Construction of a dendogram showed similarities among geographically close localities where phenological stages of sicklepod plants were similar. Analysis of correspondence based on the correlation matrix showed that Eigen values of the three first axes explain only 40.1% of the observed variation. Correlation among the scores produced by species Eigenvectors in each locality on axis 1 and the latitude, altitude, and phenological stage showed that only phenological stage was correlated (r = 0.45,P = 0.02). The results indicate that weather will not be a limiting factor for the establishment of these insect species in an environmental gradient similar to that of the surveyed area (12 to 22° latitude and 6 to 1200 m altitude). Distribution in the ordinal space of axes 1 and 2 showed thatAgrilus oceanicum(Buprestidae),Fundella argentina(Pyralidae),Thyphedanus undulatus(Hesperidae), andPhoebis sennae(Pieridae) are grouped and separated from the others in axis 2, suggesting that these species co-occur with each other. Based on their feeding guilds, multiple introduction of these species can be considered. Multivariate analysis showed potential to be used as an additional tool to help in the selection of candidates for biocontrol agents.

A Digital Object Identifier (DOI) disponibilizada pela revista não corresponde A joaninha asiática, Harmonia axyridis (Pallas, 1773), foi primeiramente registrada no Brasil em 2002 no Estado do Paraná, sendo posteriormente registrada nos estados de São Paulo e Minas Gerais. Essa espécie pode colonizar novas áreas e tornar-se dominante na comunidade local, reduzindo a densidade e diversidade de espécies nativas, principalmente de coccinelídeos. O objetivo deste trabalho foi registrar a presença de H. axyridis no Distrito Federal, a flutuação populacional e a sua co-ocorrência com outros coccinelídeos. As coletas foram realizadas em uma propriedade rural particular em Taguatinga e no campo experimental da Embrapa Hortaliças no Gama, Distrito Federal, entre agosto/2008-janeiro/2010, utilizando coleta direta dos indivíduos sobre as plantas. Foram coletados 881 coccinelídeos, sendo que destes 110 pertencem à espécie H. axyridis exclusivamente do grupo succinea, nas seguintes plantas: tomate, coentro, milho verde, repolho, couve, couve-flor, brócolis, pepino. Também foi observada a sua co-ocorrência com outras espécies de joaninhas: Cycloneda sanguinea (Linnaeus, 1763), Hippodamia convergens (Guerin-Meneville 1842), Eriopis connexa (German, 1824), Scymnus sp., Nephaspis sp., Azya luteipes (Mulsant, 1850), Hyperaspis festiva (Mulsant, 1850), Olla v-nigrum (Mulsant, 1866), Psyllobora sp. e Coleomegilla maculata (De Geer, 1775). Até o momento, não foram registradas interações negativas de H. axyridis com essas espécies no Distrito Federal. Além disso, esta região foi apontado anteriormente como tendo uma baixa probabilidade de ocorrência para esta espécie, refletindo H. axyridis grande plasticidade adaptativa para novos habitats. The multicolored Asian lady beetle, Harmonia axyridis (Pallas, 1773), was first recorded in Brazil in 2002 in Paraná state and subsequently observed in Santa Catarina, Rio Grande do Sul and Minas Gerais. This species can spread to new areas and become dominant in the local community, reducing the density and diversity of native species, mainly Coccinellidae. The objective of this work was to record for the first time the occurrence of H. axyridis in the Federal District and its co-occurrence with other Coccinellidae species. The individuals were collected directly from plants at an organic farm in Taguatinga and in experimental fields of Embrapa Hortaliças, located in the Federal District, from August 2008 to January 2010. We collected 881 Coccinelids, and of these, 110 belong to the species H. axyridis. These were found exclusively on the following plants of the succinea group: maize, cabbage, cauliflower, broccoli, kale, cucumber, cotton, tomato and coriander. We also observed its co-occurrence with the following lady beetle species: Cycloneda sanguine (Linnaeus, 1763), Hippodamia convergens (Guerin-Meneville 1842), Eriopis connexa (German, 1824), Scymnus sp., Nephaspis sp., Azya luteipes (Mulsant, 1850), Hyperaspis festiva (Mulsant, 1850), Olla v-nigrum (Mulsant, 1866), Psyllobora sp. and Coleomegilla maculata (De Geer, 1775). So far, we have not found any negative interactions between H. axyridis and these species. This is the northernmost H. axyridis record in Brazil. Moreover, the region was previously considered to have a low probability of occurrence for this species. Therefore, this record confirms that H. axyridis presents great adaptive plasticity to new habitats.

The behaviour of Elasmopalpus lignosellus associated to sex pheromone release was studied at 25 ± 1°C and 72 ± 2% RH, under a 14L: 10D photoperiod. Seventy per cent of the females started sex pheromone release two nights following emergence. The calling behaviour was limited to the last half of scotophase, initiating around the fifth hour and continuing until the end of the night. The mean onset of calling time changed with female age. Older females called earlier than younger afier the onset of scotophase. This change in the onset of calling was accompanied by an increase in total time calling. Older females spent more time in calling behaviour. It was observed that calling behaviour is governed by a circadian rhythrn. KEY WORDS: Insecta, calling behaviour, circadian rhythrn, photoperiod.

The boll weevil causes serious damage to the cotton crop in South America. Several studies have been published on this pest, but its phenology and behavior under the tropical conditions prevailing in Brazil are not well-known. In this study the feeding behavior and main food sources of adult boll weevils throughout the year in Central Brazil was investigated. The digestive tract contents of insects captured in pheromone traps in two cotton fields and two areas of native vegetation (gallery forest and cerrado sensu stricto) were analyzed. The insect was captured all through the year only in the cerrado. It fed on pollen of 19 different plant families, on Pteridophyta and fungi spores and algae cysts. Simpson Index test showed that the cerrado provided greater diversity of pollen sources. In the beginning of the cotton cycle, the plant families used for pollen feeding were varied: in cotton area 1, the weevil fed on Poaceae(50%), Malvaceae and Smilacaceae (25% each); in cotton area 2 the pollen sources were Malvaceae (50%), Asteraceae (25%) and Fabaceae and Clusiaceae (25% each); in the cerrado they were Chenopodiaceae (67%) and Scheuchzeriaceae (33%). No weevils were collected in the gallery forest in this period. After cotton was harvested, the family Smilacaceae was predominant among the food plants exploited in all the study areas. These results help to explain the survivorship of adult boll weevil during cotton fallow season in Central Brazil and they are discussed in the context of behavioral adaptations to the prevailing tropical environmental conditions.

O objetivo deste trabalho foi desenvolver um protocolo experimental para avaliar o impacto do algodoeiro Bt na bionomia e na escolha de plantas para colonização pelo pulgão-do-algodoeiro (Aphis gossypii). A bionomia do pulgão foi avaliada em casa de vegetação com insetos criados em gaiolas individuais com plantas de algodão Bt, da variedade DP 404 BG (Bollgard), ou sua isolinha não transformada DP 4049. Gaiolas contendo vasos com plantas de algodoeiro Bt e não-Bt foram usadas como arena de escolha, para a avaliação de preferência de adultos alados. O período pré-reprodutivo e reprodutivo, a longevidade, a curva de sobrevivência, a produção de prole total e diária por fêmea e a curva acumulada de produção de prole da população não apresentaram diferenças significativas. Não foi observada diferença na escolha de plantas para colonização por indivíduos alados, o que indica taxas equivalentes de colonização nas populações iniciais. O algodoeiro Bt não afeta a dinâmica populacional de A. gossypii e não aumenta seu potencial de risco como praga. The objective of this work was to develop an experimental protocol to assess the impact of Bt cotton on bionomics and on plant choice for Aphis gossypii colonization. The bionomics of the cotton aphid was assessed in greenhouse with insects reared in individual cages containing Bt cotton plants of the variety DP 404 BG (Bollgard) or its nontransformed isoline DP 4049. Cages with Bt cotton and non-Bt cotton were used as choosing arena for evaluation of winged adults preference. There was no significant difference for pre-reproduction period (immature phase), reproduction period, longevity, survivorship curve total and daily production of offspring by female, and curve of accumulated production of offspring by the population. There was no preference of colonization for any plant by winged adults, which indicates equivalent rates of colonization of the initial populations. Bt cotton plants do not affect the population dynamics of A. gossypii, and do not increase its potential risk as pest.

Olfactometer bioassays showed that odors from mature Thyanta perditor males attracted females but not males. Furthermore, odors from females did not attract either sex, indicating that like other phytophagous pentatomid bugs, the males produce a sex pheromone. Attraction appeared to peak in late afternoon to evening. The headspace volatiles collected from male and female T. perditor were analyzed by GC-MS and HPLC. A male-specific compound, methyl (2E,4Z,6Z)-decatrienoate (2E,4Z,6Z-10:COOMe), was identified along with a number of other compounds found in extracts from both sexes. Bioassays carried out with 2E,4Z,6Z-10:COOMe showed it was as attractive to females as the crude extract of male volatiles, suggesting that the male-produced sex pheromone consists of 2E,4Z,6Z-10:COOMe as a single component. Consecutive volatiles collections from males showed that 2E,4Z,6Z-10:COOMe began appearing in extracts from males about 9 d after the final molt, as the males became sexually mature.

– The objective of this research was to evaluate the parasitism behavior of Telenomus podisiAshmead, Trissolcus basalis (Wollaston) e Trissolcus urichi Crawford (Hymenoptera: Scelionidae) oneggs of Nezara viridula L., Euschistus heros F., Piezodorus guildinii Westwood and Acrosternumaseadum Rolston (Heteroptera: Pentatomidae), in no choice and multiple choice experiments. For allparasitoid species, the results demonstrated the existence of a main host species that maximizes thereproductive success. The competitive interactions among the parasitoid species were investigated inexperiments of sequential and simultaneous release of different combinations of parasitoid pairs on thehosts N. viridula, E. heros and A. aseadum. Exploitative competition was observed for egg batches atthe genus level ( Telenomus vs. Trissolcus) and interference competition at the species level ( T. basalisvs. T. urichi). Trissolcus urichi was the most aggressive species, interfering with the parasitism ofT. basalis. Generally, T. basalis showed an opportunistic behavior trying to parasitise eggs after T. urichihad abandoned the egg batch. The selection of parasitoid species for use in augmentative biologicalcontrol programs should take into account the diversity of pentatomids present in soybean in additionto the interactions among the different species of parasitoids.Index terms: parasitism, host-parasite relations, biological competition, pest control methods.Interacoes inter-guilda e intra-guilda entre especies de parasitoides de ovosque atacam o complexo de percevejos da sojaResumo – O objetivo desta pesquisa foi avaliar o comportamento de parasitismo de Telenomus podisiAshmead, Trissolcus basalis (Wollaston) e Trissolcus urichi Crawford (Hymenoptera: Scelionidae)em ovos de Nezara viridula L., Euschistus heros F., Piezodorus guildinii Westwood e Acrosternumaseadum Rolston (Heteroptera: Pentatomidae), em experimentos de multipla escolha e sem escolha dehospedeiros. Todas as especies de parasitoides testadas demonstraram possuir um hospedeiro quemaximizou a sua capacidade reprodutiva. As interacoes competitivas entre especies de parasitoidesforam investigadas mediante experimentos de liberacao sequencial e simultânea de diferentescombinacoes de pares de especies de parasitoides em N. viridula, E. heros e A. aseadum. Competicaopor exploracao foi observada a nivel de genero ( Telenomus vs. Trissolcus) e competicao por interferenciaa nivel de especie (T. basalis vs. T. urichi). A especie mais agressiva foi T. urichi, interferindo noparasitismo de T. basalis. Geralmente, T. basalis apresentou um comportamento oportunista tentandoparasitar os ovos apos T. urichi ter abandonado os lotes de ovos. A selecao de especies de parasitoidespara uso em programas de controle biologico aumentativo deve considerar a diversidade depentatomideos presentes na soja, alem das interacoes entre as especies de parasitoides que serao liberadas.Termos para indexacao: parasitismo, relacao parasita-hospedeiro, competicao biologica, metodos decombate as pragas.

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. 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.