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Ticks (Ixodida) are ecologically important ectoparasites that may impact human health and economic activities. Parasitoid wasps are natural enemies of ticks and a potential option for its biological control. In the present study, we recorded parasitism of the nymphs of the tick Amblyomma nodosum by the parasitoid wasp Ixodiphagus hookeri. The ticks, in turn, were parasitizing white-bearded manakins, Manacus manacus (Passeriformes: Pipridae) in the União Biological Reserve, one of the last major remnants of lowland rainforest in Rio de Janeiro state, southeastern Brazil. During the collection of ectoparasites from two manakins in this reserve, 20-30 parasitoid wasps hatched spontaneously from two of the ticks collected. The species of the tick nymphs and adult wasps were identified using morphological traits and molecular analyses. This record is the first documented case of I. hookeri parasitizing A. nodosum and the first time that parasitoid wasps have been found in ticks parasitizing birds in Brazil. This is also the first record of Ixodiphagus from southeastern Brazil in more than a century, with the only other record dating back to 1914. The record presented here provides valuable new information on the biology of this tick and its parasitoids, and new insights into this interspecific interaction. Further research on these vertebrate-tick-wasp interactions will be necessary to better understand the respective roles of the organisms involved in these processes.

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Trichoderma is a saprophytic fungus that is used worldwide as a biocontrol and biofertilizer agent. Although considered nonpathogenic until recently, reports of human infections produced by members of the Trichoderma genus are increasing. Numerous sources of infection were proposed based upon patient data and phylogenetic analysis, including air, agriculture, and healthcare facilities, but the deficit of knowledge concerning Trichoderma infections makes patient treatment difficult. These issues are compounded by isolates that present profiles which exhibit high minimum inhibitory concentration values to available antifungal drugs. The aim of this review is to present the global distribution and sources of infections that affect both immunocompetent and immunocompromised hosts, clinical features, therapeutic strategies that are used to treat patients, as well as highlighting treatments with the best responses. In addition, the antifungal susceptibility profiles of Trichoderma isolates that have emerged in recent decades were examined and which antifungal drugs need to be further evaluated as potential candidates to treat Trichoderma infections are also indicated.

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The decision to import and release biological control agents is a national one that may involve various authorities. It will be overseen by the national plant protection organisation that implements the responsibilities described in the International Plant Protection Convention. This article provides an overview of the decision processes and roles of these authorities in Argentina. Argentina has a long history of coordination with the other Southern Cone nations on plant protection and other technical sanitary and phytosanitary matters associated with trade. This article reports on 25 years of evaluation, import and release of exotic biological control agents. Not a single import with a permit has faced rejection on the basis of phytosanitary requirements. This record highlights the region's commitment to integrated pest management approaches that rely on international shipments of live insects and other beneficial organisms.

La décision d'importer et d'autoriser des lâchers d'agents de lutte biologique est du ressort national, avec la participation de plusieurs autorités compétentes. Elle est supervisée par l'organisation nationale de protection des végétaux, qui est chargée d'exercer les responsabilités prévues au titre de la Convention internationale pour la protection des végétaux. Les auteurs donnent une vue d'ensemble des procédures décisionnelles et des fonctions respectives des autorités compétentes en Argentine. L'Argentine et les autres nations du Cône Sud ont une longue histoire commune de coordination de la protection des végétaux et d'autres questions sanitaires et phytosanitaires en lien avec les échanges internationaux. Les auteurs font le point sur 25 années d'évaluations, d'importations et de lâchers d'agents de lutte biologique exotiques dans le pays. Aucune importation ayant fait l'objet d'une autorisation préalable n'a été rejetée pour des motifs de conformité phytosanitaire. Ce constat souligne l'engagement fort de la région en faveur de méthodes intégrées de gestion des nuisibles reposant sur le transport international d'insectes vivants et d'autres organismes utiles.

La de importar y liberar al medio agentes de control biológico es una decisión de carácter nacional en la que pueden intervenir diversas autoridades y que supervisará la organización nacional de protección fitosanitaria encargada de trasladar a la práctica las responsabilidades enunciadas en la Convención Internacional de Protección Fitosanitaria. Los autores presentan a grandes líneas los procesos decisorios y las funciones de dichas autoridades en la Argentina, país que tiene una larga trayectoria de coordinación con otras naciones del Cono Sur en materia de protección de los vegetales y otras cuestiones técnicas de índole sanitaria y fitosanitaria ligadas al comercio. Los autores dan cuenta de 25 años de evaluación, importación y liberación al medio de agentes exóticos de control biológico. En ese tiempo, ni una sola importación provista de permiso ha sido denegada en aplicación de requisitos fitosanitarios. Semejante historial pone de relieve el compromiso de la región con fórmulas de gestión integrada de plagas que reposan en los envíos internacionales de insectos vivos y otros organismos beneficiosos.

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RESUMEN Las actinobacterias incluyen miembros productores de compuestos multipropósitos restringidamente sobreexplotados al género Streptomyces. No obstante, es necesario reorientar la exploración de bacterias no estreptomiceas para el uso de nuevos bioagentes ecológicos con miras a evitar redescubrimientos y contrarrestar la resistencia a insecticidas químicos en Aedes aegypti. En esta investigación, se caracterizó actinobacterias formadoras de biopelículas para evaluar su dinámica de crecimiento, actividad larvicida y efectos subletales. La identificación, crecimiento y bioactividades de los patógenos se realizaron por cultivos, análisis de imágenes por fotomicrografía y bioensayos. Las biopelículas pertenecen a Pseudonocardiaceae (PsA1TA) y Corynebacteriaceae (CoA2CA) característicamente dependientes a crecer sobre sustratos con revestimiento cuticular específico. PsA1TA coloniza estructuras membranosas de tórax y abdomen de larvas. Las microcolonias desarrollan infectivamente a biopelículas mono y biestratificadas hasta cubrir cuatro veces la amplitud toracoabdominal (envergadura infectiva entre 1010 μm a 1036 μm). En contraste, CoA2CA envuelve radialmente estructuras esclerotizadas cefálica y anal al triplicar la amplitud de los órganos infectados (envergadura infectiva: 1820 a 2030 μm y 1650 a 1860 μm, respectivamente). Las biopelículas ejercen mortalidad diferenciada a todas las etapas larvarias, no obstante, PsA1TA resultó más mortal y virulento frente al segundo estadio (58 %-96 horas, TL50: 3,4 días), mientras que CoA2CA lo fue sobre el cuarto estadio larval (85 %-96 horas, TL50: 2,5 días). CoA2CA indujo emergencia incompleta de farados y despliegue de tarsos curvos en adultos emergentes, además de revestir cadáveres larvarios con robustas biopelículas. Los morfotipos actinobacterianos revelan efecto larvicida y subletal en A. aegypti por formación de biopelículas.

ABSTRACT Actinobacteria include several ubiquitous members involved in the synthesis of multipurpose bioactive compounds strictly derived from the genus Streptomyces. Nevertheless, new bacterial consortia based on non-streptomycetes actinobacteria are needed to be explored in order to avoid rediscoveries and minimize the development of insecticide resistance in Aedes aegypti. In accordance with the use of eco-friendly bioagents, in this study biofilm-forming actinobacteria were characterized on the basis of assessment their growth dynamics, larvicidal mortality and sublethal effects. Actinobacteria identification, biofilm growth and larvicidal bioactivities were performed by employing bacterial cultures, photomicrograph-based image analysis and bioassays. Bacterial morphotypes belong to Pseudonocardiaceae (PsA1TA) and Corynebacteriaceae (CoA2CA), which showed a distinctly substrate-dependent growth. PsA1TA microcolonies were randomly distributed on abdominal and thoracic membranous epicuticle. Afterwards, the thickness of mono-and bi-layered biofilms were increased fourfold the larval thoracoabdominal width (infectious breadth, 1010 μm - 1036 μm). In contrast, cephalic and anal sclerotized structures were radially encased by CoA2CA biofilms and increased threefold the size of both structures (infectious breadth, 1820 - 2030 μm y 1650 - 1860 μm, respectively). Although biofilms caused dissimilar mortality rates on the four larval instars, PsA1TA exerted highest larvicidal activity and virulence on second instar larvae (58 %-96 hours, LT50: 3.4 days) y CoA2CA on fourth instar larvae (85 %-96 hours, LT5G: 2.5 days). CoA2CA also induced incomplete release of pharate individuals as well as buckled protruding tarsi in newly emergent adults, whilst larval cadavers were overwhelmingly encased within massive biofilm aggregates. Biofilm-forming actinobacteria performed biolarvicidal activity and sublethal responses in A. aegypti.

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Parasitoids of three mealybug pests (Hemiptera: Pseudococcidae), Planococcus ficus (Signoret), Pseudococcus sociabilis Hambleton, and Pseudococcus viburni (Signoret) have been identified for the first time in Brazil. Mealybugs were collected in fruit-growing areas along southern Brazil during 2013-2016. An integrative approach, combining morphological and molecular methods, was used to identify the Brazilian parasitoids to the species level. Fifteen species were recorded, including 14 primary parasitoids belonging to Encyrtidae and Platygastridae and a single secondary parasitoid species belonging to Signiphoridae. The encyrtid parasitoids Acerophagus flavidulus (Brèthes), Anagyrus calyxtoi Noyes and Zaplatycerus sp., and the signiphorid secondary parasitoid Chartocerus axillaris De Santis are reported for the first time in Brazil.

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Silverleaf is caused by the fungus Chondrostereum purpureum, which produces wood necrosis and foliar silvering in woody plants. Field observations and studies in apple have shown the reversion of foliar symptoms. Because plants were clones and received identical agronomical management, it was hypothesized that reversion is driven by endophytic microbiota. Thus, the objectives of this study were to compare healthy, diseased, and reverted plants with respect to their physiology, endophytic microbial communities, antagonistic ability of their endophytes against C. purpureum, and defense genes expression. Water potential, stomatal conductance, chlorophyll content, and fluorescence were measured. Endophytic bacterial and fungal DNA were analyzed by denaturing gradient gel electrophoresis, and community richness and similarity were calculated. Wood cores were collected and bacterial and fungal endophytes were isolated and confronted with C. purpureum-virulent strains in dual-culture assays. Defense genes expression was measured by quantitative PCR. Results indicated that there were no differences in physiological parameters between healthy and reverted plants, except for fluorescence, and both type of plants differed from diseased ones. Bacterial and fungal community richness was similar in healthy and reverted plants and higher than in diseased ones. Endophytes from reverted and healthy plants showed high antagonism to C. purpureum. Furthermore, nonexpressor of pathogenesis-related gene 1 expression was upregulated in reverted plants, whereas phenylalanine ammonia lyase and polygalacturonase-inhibiting protein genes showed higher values in diseased plants. Overall, physiological, molecular, and microbial characteristics were similar between healthy and reverted plants, and both differed from diseased ones. Therefore, reversion of symptoms is associated with changes in the endophytic microbiota, which seems to be a promising source of biological control agents against C. purpureum.

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Introduction: Entomopathogenic fungi have been used as biological control agents of insect pests and have demonstrated a promising ability to colonize as endophytes a wide range of plant species. Objective: The aims of this study were to evaluate, in pepper plants, the most effective Beauveria bassiana inoculation techniques. In order to evaluate the presence of natural endophytes and its interaction with B. bassiana. Also to assess the effect of B. bassiana on the aphid Myzus persicae pepper leaf feeding preference and growth. Methods: Three inoculation techniques were evaluated: leaf spraying, seed immersion and root dipping. The pepper plants were inoculated with a conidia suspension adjusted to 1×108 conidia/ml. The presence of B. bassiana in the seedlings was evaluated at 7, 15 and 28 days after inoculation. Results: We found significant statistical differences between inoculation techniques. Foliar spraying showed the highest B. bassiana colonizationfrequency. The natural endophytes presented higher presence in the treatments in which B. bassiana had a low presence. This might indicate the occurrence of antifungal activity that interferes with the establishment of the entomopathogen in pepper tissues. We did not find statistical differences between inoculated and control pepper leaves with regard to the mortality and reproduction of the aphid pest M. persicae. However, the inoculation with B. bassiana showed a tendency to increase the mortality of adults and to decrease the offspring (nymphs). We did not find significant differences in the feeding preference between inoculated and control leaves, although there was a higher number of individuals on control leaves compared to those inoculated. Conclusions: The strain B. bassiana LPSC 1067 was established effectively as an endophyte in the pepper tissues. The most effective inoculation technique was leaf spraying. We did not find differences of statistical significance with regard to the mortality and reproduction of the aphid pest M. persicae. However, the inoculation with B. bassiana showed a tendency to increase the mortality of adults and to decrease the offspring (nymphs). Future studies evaluating the indirect effects of endophytic entomopathogens on both plants and herbivorous insects are needed to further explore their potential use in the management of insect pests.

Introducción: Los hongos entomopatógenos se han utilizado como agentes de control biológico de plagas de insectos y han demostrado una capacidad prometedora para colonizar una amplia gama de especies de plantas como endófitos. Objetivo: Los objetivos de este estudio fueron: evaluar las técnicas de inoculación más efectivas para B. bassiana en plantas de pimiento; evaluar la presencia de endófitos naturales y su interacción con B. bassiana y evaluar el efecto de B. bassiana sobre la preferencia de alimentación de la hoja de pimiento y el crecimiento de la plaga de áfidos M. persicae. Métodos: Se evaluaron tres técnicas de inoculación: aspersión foliar, inmersión de semillas e inmersión de raíces. Las plantas de pimiento se inocularon con una suspensión de conidias ajustada a 1x108 conidias/ml. La presencia de B. bassiana en las plántulas se evaluó a los 7, 15 y 28 días después de la inoculación. Resultados: Se encontraron diferencias significativas entre las técnicas de inoculación. La aspersión foliar mostró la frecuencia más alta. Los endófitos naturales presentaron frecuencias más altas en los tratamientos en los que B. bassiana tuvo una frecuencia baja, esto podría indicar la presencia de actividad antifúngica que interfiere con el establecimiento del entomopatógeno en los tejidos de pimiento. No se encontraron diferencias significativas en la mortalidad, reproducción y preferencia alimentaria de M. persicae. Conclusiones: Se demostró que la cepa B. bassiana LPSC 1067 se estableció efectivamente como endófito en los tejidos de pimiento. La técnica de inoculación más efectiva fue la aspersión foliar. No se encontraron diferencias significativas con respecto a la mortalidad, reproducción y preferencia alimentaria de M. persicae. Sin embargo, la inoculación con B. bassiana mostró una tendencia a aumentar la mortalidad de los adultos y a disminuir la descendencia (ninfas). Se necesitan estudios futuros que evalúen los efectos indirectos de los entomopatógenos endofíticos tanto en plantas como en insectos herbívoros para explorar más a fondo su posible uso en el manejo de insectos plaga.

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Dados de vigilância epidemiológica apontam uma crescente associação entre o consumo de hortaliças e surtos de origem alimentar. São inúmeras as fontes de contaminação aos quais os vegetais estão sujeitos ao longo da cadeia produtiva. Estudos sugerem que práticas agrícolas, como o uso de adubo constituído por esterco animal e água de irrigação não tratada, podem aumentar o risco de contaminação por micro-organismos patogênicos. Com as restrições ao uso de pesticidas sintéticos no sistema orgânico de produção agrícola, agentes de controle biológico, como Bacillus thuringiensis (Bt) desempenham um importante papel para a garantia da produtividade. No entanto, recentemente, a segurança do uso de Bt passou a ser questionada em função da possibilidade de produzir enterotoxinas. Este estudo teve por objetivos levantar dados sobre práticas adotadas no cultivo de hortaliças orgânicas no Estado de São Paulo, Brasil e sobre as características microbiológicas de fertilizantes, água de irrigação, água de lavagem e alfaces nas etapas pré e pós-colheita, assim como avaliar a persistência e interações entre Bt e Salmonella em hortaliças, visando contribuir para avaliações de risco microbiológico mais adequadas. Na primeira parte do estudo, dez propriedades de cultivo orgânico certificadas foram visitadas para a obtenção de dados sobre práticas adotadas e para a coleta de amostras para análise microbiológica. As amostras foram submetidas à enumeração e identificação (gênero e espécie) de Enterobacteriaceae; pesquisa de Salmonella spp. por método convencional e qPCR; e enumeração de coliformes totais e Escherichia coli nas amostras de água. Na segunda fase da pesquisa, avaliou-se a persistência e as interações entre Bt e Salmonella Montevideo no pré e pós-colheita de espinafres. Por fim, bactérias epifíticas isoladas de hortaliças foram testadas quanto a capacidade de inibir bactérias do grupo Bacillus cereus e cepas de Salmonella enterica. As contagens de Enterobacteriaceae variaram de <1 a 7,2 ± 0,1 log UFC/g nos fertilizantes, de 4,1 ± 0,3 a 5,6 ± 0,3 log UFC/g nas alfaces coletadas nos canteiros, de 2,9 ± 0,6 a 5,3 ± 0,5 log UFC/g nas alfaces lavadas, de <1 a 3,5 ± 0,1 log UFC/mL nas amostras de água de irrigação e de <1 a 3,0 ± 0,3 log UFC/mL nas amostras de água de lavagem. Salmonella não foi isolada por cultivo em placa, mas foi detectada por qPCR em uma amostra de alface orgânica lavada. Utilizando MALDI-TOF MS, 45 espécies pertencentes a 24 gêneros bacterianos foram identificadas na cadeia produtiva de hortaliças orgânicas. Bt foi capaz de persistir nas folhas de espinafre nas etapas pré e pós-colheita e afetou a persistência de Salmonella durante o cultivo, mas não durante o armazenamento pós-colheita a 12 ºC. Não foi observada tendência de germinação dos esporos de Bt após a aplicação nos espinafres, reduzindo assim a possibilidade de multiplicação e produção de enterotoxinas. A bactéria epifítica Pseudomonas chlororaphis, isolada de hortaliça, foi capaz de inibir membros do grupo Bacillus cereus, incluindo cepas patogênicas e Bt em testes in vitro, sugerindo uma barreira biológica para o controle da multiplicação destes micro-organismos. Este estudo traz importantes informações sobre a segurança microbiológica de hortaliças orgânicas e de práticas agrícolas, evidenciando a importância de boas práticas para a promoção do alimento seguro. Os resultados constituem uma importante contribuição para o desenvolvimento de modelos de avaliação de risco microbiológico e prevenção de surtos de origem alimentar

Epidemiological surveillance data indicate a growing association between vegetable consumption and food-borne outbreaks. There are numerous sources of contamination to which plants are subjected throughout the production chain. Studies suggest that agricultural practices such as the use of manure fertilizer and untreated irrigation water may increase the risk of contamination by pathogenic microorganisms. With the restrictions on the use of synthetic pesticides in the organic farming system, biological control agents such as Bacillus thuringiensis (Bt), play an important role in ensuring productivity. However, the safety of Bt has recently been questioned due to the possibility of producing enterotoxins. This study aimed to gather information about the agricultural practices employed in the organic vegetables production fields and the microbiological characteristics of fertilizer, irrigation water, wash water, and lettuces in pre and post-harvest stages, and to evaluate the persistence and interactions between Bt and Salmonella on leafy greens, aiming to contribute for more adequate microbiological risk assessments. In the first part of the study, ten certified organic farms were visited to collect data on the farming practices and for collection of samples for microbiological evaluations. The samples were submitted to Enterobacteriaceae enumeration and identification (genus and species); Salmonella spp. by conventional method and qPCR; and enumeration of total coliforms and Escherichia coli in water samples. In the second part of the study, the persistence and interaction between Bacillus thuringiensis subsp Aizawai (Bt) and Salmonella Montevideo in the pre and post-harvest of spinach were evaluated. Finally, epiphytic bacteria isolated from vegetables were tested for their ability to inhibit growth of Bacillus cereus group members and Salmonella strains. Enterobacteriaceae counts ranged from <1 to 7.2 ± 0.1 log CFU/g in fertilizers, from 4.1 ± 0.3 to 5.6 ± 0.3 log CFU/g in lettuces collected from the fields, from 2.9 ± 0.6 to 5.3 ± 0.5 log CFU/g in washed lettuces, <1 to 3.5 ± 0.1 log CFU/mL in irrigation water and <1 to 3.0 ± 0.3 log CFU/mL in wash water. Salmonella was not isolated by plating but it was detected by qPCR in one sample of washed organic lettuce. Using MALDI-TOF MS, 45 species belonging to 24 bacterial genera were identified in the organic vegetable production chain. Bt was able to persist on pre and post-harvest of spinach and affected Salmonella persistence during cultivation, but not during the storage at 12 ºC. Bt spores showed no tendency to germinate during pre-harvest of spinach, thus reducing the probability of growth and production of enterotoxins. The epiphytic bacterium Pseudomonas chlororaphis isolated from one vegetable sample was able to inhibit members of the Bacillus cereus group, including pathogenic strains and Bt in in vitro tests, suggesting a biological barrier to control the multiplication of these microorganisms. These studies provide important information about the microbiological safety of organic vegetables and agricultural practices, highlighting the importance of good practices for the promotion of safe food. These data are fundamental for the development of microbiological risk assessment models and prevention of foodborne outbreaks

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ABSTRACT: Aleurocanthus woglumi is an exotic pest, widely disseminated in Brazil, with a high preference for citrus plants, but with a polyphagous feeding habit. The contribution of the state of Rio de Janeiro in the Brazilian production of citrus fruits is small; however, there are still public policies that encourage citrus production in the state. In 2010, the appearance of this pest in Rio de Janeiro was confirmed in the municipality of Cachoeiras de Macacu. The objectives of this research were to evaluate the dissemination of A. woglumi in this state, conduct a survey of new species of host plants, identify and evaluate the population of natural enemies present at two orchards that grow 'Tahiti' limes ( Citrus latifolia ) infested by the pest in Cachoeiras de Macacu, RJ, Brazil. In 19 municipalities, leaves of citrus and other species of plants presenting aleyrodid nymphs were collected, and yellow sticky traps were installed to capture adults for subsequent identification. At the 'Tahiti' lime orchards, the leaf collections were done to confirm the species of Aleyrodidae , and regarding A. woglumi , the natural enemies associated with this pest were collected directly from the infested plants. The results showed that A. woglumi is wide-spread in 12 municipalities. Three new host plants for A. woglumi were identified: Artocarpus heterophyllus ( Moraceae ) , Pouteria caimito ( Sapotaceae ) and Struthanthus flexicaulis ( Loranthaceae ). In Cachoeiras de Macacu, a new species of parasitoid of A. woglumi nymphs was named: Encarsia pergandiella (Hymenoptera: Aphelinidae ), while the insects in the Coccinellidae (Coleoptera) family have stood out as predators of this pest.

RESUMO: Aleurocanthus woglumi é uma praga exótica, amplamente disseminada no Brasil, com grande preferência pelos citros, mas com hábito alimentar polífago. A participação do estado do Rio de Janeiro na produção brasileira de citros é pequena; todavia, ainda ocorrem políticas públicas de incentivo à citricultura no Estado. Em 2010, a ocorrência dessa praga no estado do Rio de Janeiro foi confirmada no município de Cachoeiras de Macacu. Os objetivos deste trabalho foram avaliar a disseminação de A. woglumi nesse Estado, levantar novas espécies de plantas hospedeiras, identificar e avaliar a população de seus inimigos naturais presentes em dois pomares de lima-ácida ( Citrus latifolia ) 'Tahiti', infestados pela praga em Cachoeiras de Macacu, RJ, Brasil. Foram realizadas coletas de folhas de citros e de outras espécies de plantas com presença de ninfas de aleirodídeos em 19 municípios, e armadilhas adesivas amarelas foram instaladas para a captura de adultos, para posterior identificação. Nos pomares de lima-ácida, coletas de folhas foram feitas para confirmar a espécie de aleirodídeo e, em se tratando de A. woglumi , coletaram-se inimigos naturais associados a essa praga diretamente nas plantas infestadas. Os resultados mostraram que A. woglumi está disseminada em 12 municípios. Três novas espécies de plantas hospedeiras de A. woglumi foram identificadas: Artocarpus heterophyllus ( Moraceae ), Pouteria caimito ( Sapotaceae ) e Struthanthus flexicaulis ( Loranthaceae ). Em Cachoeiras de Macacu, uma nova espécie de parasitoide de ninfas de A. woglumi foi assinalada: Encarsia pergandiella (Hymenoptera: Aphelinidae ), enquanto que os insetos representantes da família Coccinellidae (Coleoptera) se destacaram como predadores dessa praga.

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Aleurocanthus woglumi is an exotic pest, widely disseminated in Brazil, with a high preference for citrus plants, but with a polyphagous feeding habit. The contribution of the state of Rio de Janeiro in the Brazilian production of citrus fruits is small; however, there are still public policies that encourage citrus production in the state. In 2010, the appearance of this pest in Rio de Janeiro was confirmed in the municipality of Cachoeiras de Macacu. The objectives of this research were to evaluate the dissemination of A. woglumi in this state, conduct a survey of new species of host plants, identify and evaluate the population of natural enemies present at two orchards that grow 'Tahiti' limes (Citrus latifolia) infested by the pest in Cachoeiras de Macacu, RJ, Brazil. In 19 municipalities, leaves of citrus and other species of plants presenting aleyrodid nymphs were collected, and yellow sticky traps were installed to capture adults for subsequent identification. At the 'Tahiti' lime orchards, the leaf collections were done to confirm the species of Aleyrodidae , and regarding A. woglumi , the natural enemies associated with this pest were collected directly from the infested plants. The results showed that A. woglumi is wide-spread in 12 municipalities. Three new host plants for A. woglumi were identified: Artocarpus heterophyllus (Moraceae) , Pouteria caimito (Sapotaceae) and Struthanthus flexicaulis (Loranthaceae). In Cachoeiras de Macacu, a new species of parasitoid of A. woglumi nymphs was named: Encarsia pergandiella (Hymenoptera: Aphelinidae), while the insects in the Coccinellidae (Coleoptera) family have stood out as predators of this pest.(AU)

Aleurocanthus woglumi é uma praga exótica, amplamente disseminada no Brasil, com grande preferência pelos citros, mas com hábito alimentar polífago. A participação do estado do Rio de Janeiro na produção brasileira de citros é pequena; todavia, ainda ocorrem políticas públicas de incentivo à citricultura no Estado. Em 2010, a ocorrência dessa praga no estado do Rio de Janeiro foi confirmada no município de Cachoeiras de Macacu. Os objetivos deste trabalho foram avaliar a disseminação de A. woglumi nesse Estado, levantar novas espécies de plantas hospedeiras, identificar e avaliar a população de seus inimigos naturais presentes em dois pomares de lima-ácida (Citrus latifolia) 'Tahiti', infestados pela praga em Cachoeiras de Macacu, RJ, Brasil. Foram realizadas coletas de folhas de citros e de outras espécies de plantas com presença de ninfas de aleirodídeos em 19 municípios, e armadilhas adesivas amarelas foram instaladas para a captura de adultos, para posterior identificação. Nos pomares de lima-ácida, coletas de folhas foram feitas para confirmar a espécie de aleirodídeo e, em se tratando de A. woglumi , coletaram-se inimigos naturais associados a essa praga diretamente nas plantas infestadas. Os resultados mostraram que A. woglumi está disseminada em 12 municípios. Três novas espécies de plantas hospedeiras de A. woglumi foram identificadas: Artocarpus heterophyllus (Moraceae), Pouteria caimito (Sapotaceae) e Struthanthus flexicaulis (Loranthaceae). Em Cachoeiras de Macacu, uma nova espécie de parasitoide de ninfas de A. woglumi foi assinalada: Encarsia pergandiella (Hymenoptera: Aphelinidae), enquanto que os insetos representantes da família Coccinellidae (Coleoptera) se destacaram como predadores dessa praga.(AU)

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RESUMO

BACKGROUND: Bacillus thuringiensis is the most successful biological control agent used in agriculture, forestry and mosquito control. However, the insecticidal activity of the B. thuringiensis formulation is not very stable and rapidly loses its biological activity under field conditions, due to the ultraviolet radiation in sunlight. Melanin is known to absorb radiation therefore photo protection of B. thuringiensis based on melanin has been extensively studied. OBJECTIVES: The aim of this study was to find a wild type strain of naturally melanin-producing B. thuringiensis to avoid any mutation or manipulation that can affect the Cry protein content. MATERIALS AND METHODS: Bacillus thuringiensis strains were isolated from soils of different States of Mexico and pigment extraction was followed by lowering the pH to 2 using 1N HCl. Pigment was characterized by some chemical tests based on its solubility, bleaching by H2O2 and flocculation with FeCl3, and using an Infrared (IR) spectrum. Ultraviolet (UV) irradiation experiment was performed to probe the melanin efficacy. RESULTS: ELI52 strain of B. thuringiensis was confirmed to naturally produce melanin. The Cry protein analysis suggested that ELI52 is probably a B. thuringiensis subsp. israelensis strain with toxic activity against the Diptera order of insects. Ultra Violet protection efficacy of melanin was probed counting total viable colonies after UV radiation and comparing the results with the non-producing melanin strain L-DOPA (L-3, 4-dihydroxyphenylalanine) was also detected in the culture. ELI52 strain showed an antagonistic effect over some common bacteria from the environment. CONCLUSIONS: ELI52 wild-type strain of B. thuringiensis is a good bio-insecticide that produces melanin with UV-resistance that is probably toxic against the Diptera order of insects and can inhibit the growth of other environmental bacteria.

RESUMO

Os pulgões (Hemiptera: Aphididae) são pragas de extrema importância em cereais de inverno no mundo todo. No Brasil, o programa Controle Biológico de Pulgões do Trigo liberou milhões de parasitoides (Hymenoptera: Braconidae e Aphelinidae) nas áreas tritícolas, reduzindo expressivamente a população da praga, e atualmente raramente o controle químico se faz necessário. Entretanto, desde a década de 80 poucos trabalhos de campo tem sido realizados para verificar as espécies efetivamente estabelecidas no País. Por esta razão, este estudo objetivou registrar as espécies de parasitoides de pulgões ocorrentes em lavouras de trigo na região Norte no Paraná. O trabalho foi realizado em quatro áreas comerciais de trigo, durante as safras 2008 e 2009. A captura dos parasitoides ocorreu com uso de armadilhas (Moericke e Malaise) e coleta de pulgões mumificados. No total foram encontradas seis espécies de parasitoides, Aphidius colemani, A. uzbekistanicus, A. ervi, Aphidius rhopalosiphi, Diaeretiella rapae e Lysiphlebus testaceipes. Esses resultados contribuem com a comprovação do estabelecimento de três espécies exóticas de parasitoides de pulgões no Paraná, e confirma o estabelecimento de A. rhopalosiphi no País. Ressalta-se a necessidade de estudos complementares em outras regiões do País, pois outras espécies introduzidas necessitam ter o estabelecimento comprovado.

Aphids (Hemiptera: Aphididae) are the main pest of wheat (Hemiptera: Aphididae) in several countries. In Brazil, the Biological Control of Wheat Aphids released millions of aphid parasitoids (Hymenoptera: Braconidae and Aphelinidae) on wheat fields and in the present moment the chemical control is rarely necessary. However, since the 80s few studies was carried out to evaluate the species established in Brazil. For this reason, the aim of this study was to record the species of aphid parasitoids that occur in wheat in the northern region of Parana state, Brazil. Four commercial wheat fields were investigated in the agricultural years of 2008 and 2009. The aphid parasitoids were captured with traps (Moericke and Malaise) and aphid mummified were collected. In total, six species of parasitoids were found, Aphidius colemani, A. uzbekistanicus, A. ervi, Aphidius rhopalosiphi, Diaeretiella rapae e Lysiphlebus testaceipes. These results contribute with the register of three exotic species in Parana, and confirm the establishment of A. rhopalosiphi in the country. We emphasize the need for further studies in other regions of the country, as other species introduced also need to have their establishment confirmed.

RESUMO

Os pulgões (Hemiptera: Aphididae) são pragas de extrema importância em cereais de inverno no mundo todo. No Brasil, o programa Controle Biológico de Pulgões do Trigo liberou milhões de parasitoides (Hymenoptera: Braconidae e Aphelinidae) nas áreas tritícolas, reduzindo expressivamente a população da praga, e atualmente raramente o controle químico se faz necessário. Entretanto, desde a década de 80 poucos trabalhos de campo tem sido realizados para verificar as espécies efetivamente estabelecidas no País. Por esta razão, este estudo objetivou registrar as espécies de parasitoides de pulgões ocorrentes em lavouras de trigo na região Norte no Paraná. O trabalho foi realizado em quatro áreas comerciais de trigo, durante as safras 2008 e 2009. A captura dos parasitoides ocorreu com uso de armadilhas (Moericke e Malaise) e coleta de pulgões mumificados. No total foram encontradas seis espécies de parasitoides, Aphidius colemani, A. uzbekistanicus, A. ervi, Aphidius rhopalosiphi, Diaeretiella rapae e Lysiphlebus testaceipes. Esses resultados contribuem com a comprovação do estabelecimento de três espécies exóticas de parasitoides de pulgões no Paraná, e confirma o estabelecimento de A. rhopalosiphi no País. Ressalta-se a necessidade de estudos complementares em outras regiões do País, pois outras espécies introduzidas necessitam ter o estabelecimento comprovado.

Aphids (Hemiptera: Aphididae) are the main pest of wheat (Hemiptera: Aphididae) in several countries. In Brazil, the Biological Control of Wheat Aphids released millions of aphid parasitoids (Hymenoptera: Braconidae and Aphelinidae) on wheat fields and in the present moment the chemical control is rarely necessary. However, since the 80s few studies was carried out to evaluate the species established in Brazil. For this reason, the aim of this study was to record the species of aphid parasitoids that occur in wheat in the northern region of Parana state, Brazil. Four commercial wheat fields were investigated in the agricultural years of 2008 and 2009. The aphid parasitoids were captured with traps (Moericke and Malaise) and aphid mummified were collected. In total, six species of parasitoids were found, Aphidius colemani, A. uzbekistanicus, A. ervi, Aphidius rhopalosiphi, Diaeretiella rapae e Lysiphlebus testaceipes. These results contribute with the register of three exotic species in Parana, and confirm the establishment of A. rhopalosiphi in the country. We emphasize the need for further studies in other regions of the country, as other species introduced also need to have their establishment confirmed.

RESUMO

Specimens of Cybocephalus sp. were collected preying on Aspidiotus destructor (Signoret) infesting coconut trees (Dwarf cultivar) and on Diaspis echinocacti (Bouché) present on Opuntia ficus-indica Mill. and Nopalea cochenillifera (L.) Lyons (Cactaceae). In the later case the nitidulid was associated with another predator: Coccidophilus citricola (Brèthes) (Coleoptera: Coccinellidae). The eggs were laid inside the scale of the diaspidid (one egg per scale); all life stages were detected. No sexual dimorphism was observed, and the natural sex ratio was 0.52 which represents a sexual proportion of 1.1 females : 1 male. Cybocephalus specimens were also collected preying on coccids on Alamanda cathartica L. (Apocynaceae) and on Morus alba L. (Moraceae).

Espécimes de Cybocephalus sp. foram coletados predando colônias de Aspidiotus destructor (Signoret), que infestavam coqueiros da variedade Anão, e colônias de Diaspis echinocacti (Bouché) em Opuntia ficus-indica Mill. e Nopalea cochenillifera (L.) Lyons (Cactaceae) (palmas-forrageiras); neste último caso, o nitidulídeo estava presente juntamente com outro predador: Coccidophilus citricola (Brèthes) Coleoptera: Coccinellidae). Os ovos eram postos no interior das carapaças do diaspidídeo já predadas (um ovo por carapaça), sendo que foram encontrados todos os estágios de desenvolvimento. Não foi detectado dimorfismo sexual. A razão sexual natural foi de 0,52, o que representa uma proporção sexual de 1,1 fêmeas : 1 macho. Espécimes de Cybocephalus sp. também foram coletados predando coccídeos em Alamanda cathartica L. (Apocynaceae) e em Morus alba L. (Moraceae).