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Transgenic Bt soybean plants have been developed to control insect pests, such as Anticarsia gemmatalis and Chrysodeixis includens. This objective has been achieved successfully; however, recently, some authors claimed that Bt soybean plants have been more susceptible than non-Bt soybean to Bemisia tabaci MEAM1. In addition, it is unknown whether Bt soybean plants infested by B. tabaci become less resistant to target pests. Therefore, this study aimed to evaluate: (i) whether the previous infestation with B. tabaci can compromise Bt and non-Bt soybean resistance to C. includens; (ii) the effects of B. tabaci infestations on Bt and non-Bt soybean plant growth; and (iii) whether B. tabaci feeding reduces contents of chlorophyll and carotenoids of soybean plants. Bt and non-Bt soybean plants pre-infested with B. tabaci showed no changes in resistance to C. includens. Bt soybean plants infested with B. tabaci showed a lower plant height than uninfested plants. Differently, non-Bt soybean plants exhibited no reduction in plant growth due to B. tabaci feeding. Bt soybean plants suffered a reduction in dry matter only under double infestation (B. tabaci and C. includens), while non-Bt soybean plants experienced reduction in dry matter when infested with B. tabaci and C. includens or by C. includens only. B. tabaci feeding did not alter contents of chlorophyll and carotenoids, and perhaps the reduction in plant growth was related to salivary toxins. Concluding, both Bt and non-Bt soybean plants were susceptible to B. tabaci feeding, evidencing necessity of developing soybean cultivars resistant to B. tabaci.

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The boll weevil, Anthonomus grandis grandis Boheman (Coleoptera: Curculionidae), is one of the most important pests of cotton production worldwide. The objective of this work was to develop a sequential sampling plan for the boll weevil. The studies were conducted in Maracaju, MS, Brazil, in two seasons with cotton cultivar FM 993. A 10,000-m2 area of cotton was subdivided into 100 of 10- by 10-m plots, and five plants per plot were evaluated weekly, recording the number of squares with feeding + oviposition punctures of A. grandis in each plant. A sequential sampling plan by the maximum likelihood ratio test was developed, using a 10% threshold level of squares attacked. A 5% security level was adopted for the elaboration of the sequential sampling plan. The type I and type II error used was 0.05, recommended for studies with insects. The adjustment of the frequency distributions used were divided into two phases, so that the model that best fit to the data was the negative binomial distribution up to 85 DAE (Phase I), and from there the best fit was Poisson distribution (Phase II). The equations that define the decision-making for Phase I are S0 = -5.1743 + 0.5730N and S1 = 5.1743 + 0.5730N, and for the Phase II are S0 = -4.2479 + 0.5771N and S1 = 4.2479 + 0.5771N. The sequential sampling plan developed indicated the maximum number of sample units expected for decision-making is ∼39 and 31 samples for Phases I and II, respectively.

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The cotton boll weevil Anthonomus grandis Boheman (Coleoptera: Curculionidae) is the main pest in cotton crop around the world, directly affecting cotton production. In order to establish a sequential sampling plan, it is crucial to understand the spatial distribution of the pest population and the damage it causes to the crop through the different developmental stages of cotton plants. Therefore, this study aimed to investigate the spatial distribution of adults in the cultivation area and their oviposition and feeding behavior throughout the development of the cotton plants. The experiment was conducted in Maracaju, Mato Grosso do Sul, Brazil, in the 2012/2013 and 2013/2014 growing seasons, in an area of 10,000 m2, planted with the cotton cultivar FM 993. The experimental area was divided into 100 plots of 100 m2 (10 × 10 m) each, and five plants per plot were sampled weekly throughout the crop cycle. The number of flower buds with feeding and oviposition punctures and of adult A. grandis was recorded throughout the crop cycle in five plants per plot. After determining the aggregation indices (variance/mean ratio, Morisita's index, exponent k of the negative binomial distribution, and Green's coefficient) and adjusting the frequencies observed in the field to the distribution of frequencies (Poisson, negative binomial, and positive binomial) using the chi-squared test, it was observed that flower buds with punctures derived from feeding, oviposition, and feeding + oviposition showed an aggregated distribution in the cultivation area until 85 days after emergence and a random distribution after this stage. The adults of A. grandis presented a random distribution in the cultivation area.

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The present study is pioneer in analyzing the chemical composition of the essential oil from aerial parts of Turnera subulata Sm. and evaluates their antibacterial activity against a panel of drug-resistant strains of Staphylococcus aureus. The aerial parts were kiln-dried and then powdered in mechanical mill, and was subjected to hydrodistillation in a Clevenger-type apparatus. The components were analyzed using a mass spectrometrycoupled gas chromatography (GC-MS), and the identification of substances was performed by comparison of the mass spectra obtained with the mass spectra of the database of the GC-MS and retention indices . The essential oil was evaluated using the method of broth dilution at concentrations ranging from 3.125µg/mL to 3200µg/mL. It was possible to identify 45 substances (92.1%) of the essential oils, and the major components were trans-caryophyllene (6.7%), citronellol (5.6%), sphatulenol (5.3%), α-cadinol (4.3%), n-tricosano (4.3%), geraniol (4.1%) and trans-geranilacetone (3.7%), n-pentacosano (3.5%), globulol (3.4%), caryophyllene oxide (3.2%). The essential oil of T. subulata Sm. showed effective antibacterial activity for the various strains of S. aureus tested, with the MIC values between 25 µg/mL and 1600 µg/mL. The study of the essential oil of Turnera subulata Sm. showed that it consists of a complex mixture of several classes of compounds having the sesquiterpenes as major constituents followed by monoterpenes, and showed an antibacterial activity significant front the strains tested.

O presente estudo é pioneiro em analisar a composição química dos óleos essenciais das partes aéreas de Turnera subulata Sm. e sua atividade antibacteriana frente à Staphylococcus aureus resistentes a antibióticos. As partes aéreas da planta foram secas em estufa, pulverizadas em moinho mecânico e submetidas à hidrodestilaçao em aparato tipo Clevenger. A composição dos óleos essenciais foi analisada por cromatografia gasosa acoplada a espectrometria de massas (CG-EM), e a identificação realizada por comparação dos espectros de massas com a biblioteca do CG-EM e índices de retenção. A atividade antimicrobiana do óleo essencial foi avaliada usando o método de diluição em caldo, em concentrações que variaram de 3.125µg/mL to 3200µg/mL. Foi possível identificar 45 substâncias (92,1%) do óleo essencial, sendo os componentes majoritários: trans-cariofileno (6,7%), citronelol (5,6%), espatulenol (5,3%), α-cadinol (4,3%), n-tricosano (4,3%), geraniol (4,1%) e trans-geranilacetona (3,7%), n-pentacosano (3,5%), globulol (3,4%) e óxido de cariofileno (3,2%). O óleo essencial de T. subulata Sm. mostrou atividade antibacteriana eficaz para as várias cepas de S. aureus testadas, com valores de CIM entre 25 µg/mL e 1600 µg/mL. O estudo do óleo essencial de Turnera subulata Sm. evidenciou sua complexa mistura, contendo várias classes de substâncias, tendo os sesquiterpenos como constituintes majoritários seguido dos monoterpenos, e mostrou significativa atividade antibacteriana frente as cepas testadas.

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This study aimed to verify the difference between flower-visiting insect communities in genetically modified cotton (Bt) and conventional cotton (non-Bt). The study was conducted in a commercial cotton field in the municipality of Maracaju, Mato Grosso do Sul, Brazil. The collections of flower visitors were performed every 3 days in the morning during the reproductive period of cotton and employed 2 treatments: Bt cotton and non-Bt cotton. By the end of flowering, 1,310 specimens were collected, 56.56% on Bt cotton flowers and 43.44% on non-Bt cotton flowers. Even though the abundance of collected insects on Bt cotton was higher, species richness in non-Bt was higher than Bt, with a diversity of 73 species on Bt cotton and 84 species on non-Bt. Species richness of flower visitors varied between sampling times for both treatments and between the days of flowering, therefore, the species richness was lower at the beginning and the end of flowering in both cotton cultivars. But the species richness did not vary between cultivars of cotton. Species composition of insects was different during the periods of flower visitation, between cotton cultivars as well as between the interaction of these two factors. There was also a variation between the days of flowering but not between days and cotton cultivars. Based on this study, it was concluded that there are differences between the species of insects that visit flowers of Bt cotton and non-Bt cotton.

O objetivo deste estudo foi verificar se existe diferença entre a comunidade de insetos visitantes florais do algodoeirogeneticamente modificado (Bt) e sua isolinha convencional (não-Bt). A pesquisa foi realizada em área de produção comercial no Município de Maracaju, MS, Brasil. A área amostral compreendeu dois campos, um de algodão não-Bt e outro de algodão Bt. As coletas dos insetos foram realizadas no período matutino com intervalo de três dias. Ao final da floração foram coletados 1.310 espécimes de visitantes florais, destes, 56,56% nas flores do algodoeiro Bt e 43,44% do não-Bt. Embora a abundância de insetos no cultivar Bt ter sido maior, a riqueza de espécies no cultivar não-Bt foi superior. Assim, apresentando diversidade de 73 espécies na cultivar Bt e 84 espécies na não-Bt. A riqueza de espécies variou entre os horários de coleta para ambos os tratamentos, entre os dias de floração onde no início e no final da floração, constatou-se a menor riqueza independentemente do cultivar de algodão. Por outro lado, a riqueza de espécies não variou entre os cultivares de algodão. Com relação à composição das espécies houve variação entre os horários de visitação, entre os tipos de algodão e também entre a interação, desses dois fatores. Também variou entre os dias de floração, mas não entre as classes da interação os dias e o tipo de algodão. Com base neste estudo, concluímos que houve diferença entre as espécies de insetos que visitaram as flores do algodoeiro Bt e sua isolinha convencional.

RESUMO

The goal of this research was to use the sequential probability ratio test to establish a sequential sampling plan for Aphis gossypii Glover and Frankliniella schultzei Trybom infesting cotton. Field work was conducted at the agricultural experimental station of the Universidade Federal da Grande Dourados during the 2003/2004 and 2004/2005 agricultural years. Aphid colonies and individual thrips in the sampling area were counted and their numbers were recorded. The spatial distribution pattern of A. gossypii and F. schultzei in the cotton culture was aggregated. Sequential sampling plans were developed for aphids and thrips with type I and type II errors set at 0.1, common Kc = 0.6081 (aphids) and = 0. 9449 (thrips), and safety and management levels of 20% (aphids) and 40% (thrips) of infested plants. The sampling plans resulted in two decision boundaries for each species, as follows: the upper boundary, indicating when management (population control) is recommended: S1 = 4.6546 + 0.2849n (aphids), and S1 = 3.6514 + 0.1435n (thrips); and the lower boundary, indicating when population control is not necessary: S0 = -4.6546 + 0.2849n (aphids) and S0 = - 3.6514 + 0.1435n (thrips). The highest probability of error when making a decision was 3% for aphids and 2% for thrips, respectively. The maximum number of samples required to reach a decision was 63 for aphids and 95 for thrips.

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ABSTRACT With the objective of identifying and quantifying the natural enemies associated to cotton pests sampling was made of these arthropods during the 2001/2002 and 2002/2003 crop season in Dourados, MS, Brazil. Evaluation was made of 100 plants in 20,000 m2, in a total of 20 samplings from 7 to 140 days after the plants' emergence, making use of the cotton cultivars DeltaOpal and Fibermax 986, in 2001/2002 and 2002/2003, respectively. In 2002/2003 samplings of the beneficial arthropods on the ground in the experimental area were made, through visual evaluations in the spaces between lines of plants in 25 plots of 100 m2 and through the utilization of 25 pitfall traps installed in each plot. For species most abundant in the ground the standard analysis was made of their spatial distribution using the Morisita index. In the two crop seasons, the Coccinellidae family was the most abundant of the complex of predators, with population levels following the fluctuation of a cotton aphid Aphis gossypii Glover population (Hemíptera: Aphididae). The suborder Heteroptera (Hemiptera) presented the highest diversity, with insects from 5 families, during the crop season 2001/2002. The pitfall trap method was more efficient than visual evaluation. Amongst the soil predators, the most abundant was Calosoma granulatumwhose standard of spatial distribution was aggregated in the experimental area.

RESUMO Com o objetivo de identificar a flutuação populacional dos inimigos naturais associados às pragas da cultura do algodoeiro, foram feitos levantamentos populacionais destes artrópodos nas safras 2001/2002 e 2002/2003 em Dourados, MS. Avaliaram-se 100 plantas ao acaso em uma área de 20.000 m2, num total de 20 amostragens dos 7 aos 140 dias após a emergência, utilizando-se as variedades DeltaOpal e Fibermax 986 em 2001/2002 e 2002/2003, respectivamente. Também, em 2002/2003 foram feitos levantamentos dos artrópodes benéficos sobre o solo da cultura, através de avaliações visuais nas entrelinhas das 25 parcelas de 100 m2, e através da instalação de 25 armadilhas do tipo pitfall. Para a espécie mais abundante dos predadores no solo foi realizada a análise padrão de sua distribuição espacial utilizando-se o índice de Morisita. Nas duas safras, a família Coccinellidae foi a mais abundante do complexo de predadores, com níveis populacionais que seguiram a flutuação populacional do pulgão Aphis gossypii Glover (Hemíptera: Aphididae). A subordem Heteroptera (Hemiptera) apresentou a maior diversidade com insetos de 5 famílias, na safra 2001/2002. O método da armadilha pitfall foi mais eficiente que a avaliação visual. Dentre os predadores de solo, o mais abundante foi Calosoma granulatum cujo padrão de distribuição espacial foi agregado.

RESUMO

Considerando-se a expansão crescente do uso e comercialização de produtos naturais nos últimos anos e a preocupação com a qualidade e segurança dos produtos anunciados na mídia, buscou-se avaliar a adequação de sua publicidade em relação à legislação vigente. Com este objetivo, foi feita a coleta de 135 peças publicitárias, anunciando 690 diferentes produtos, obtidas em cinco diferentes veículos de comunicação: impressos, revistas, jornais regionais, emissoras de TV e de rádio veiculadas no município de João Pessoa/PB, no período de outubro de 2002 a outubro de 2003. O conteúdo das peças publicitárias foi analisado, considerando-se a sua adequação a Resolução de Diretoria Colegiada (RDC) número 102/2000/ANVISA, que regula a publicidade de medicamentos. Foi observado que 97,04% das peças publicitárias anunciadas na Paraíba não se encontram coerentes com a legislação brasileira, podendo promover diversos danos aos seus usuários, como o uso indiscriminado de medicamentos, a automedicação e reações adversas

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Os autores deste estudo, tem como objetivo analisar a tendência de crianças de 0 à 24 meses, para adquirirem parasitos intestinais. Usaram uma amostra de 55 crianças que freqüentaram regularmente o serviço de Pediatria e Puericultura da Clínica Pediátrica HSPM e praticaram aos 12 meses exame protoparasitógico de fezes. O exame foi repetido aos 15, 18, 21 e 24 meses, somente das crianças cujo resultado anterior era negativo. Se verifica que já aos 12 meses 18.18% estavam parasitadas, do restante negativo, estavam contaminados aos 15 meses 44.44%, do restante aos 18 meses 32%, aos 21 meses 47.05%, chegando somente cinco crianças negativas até os 24 meses (9.09%). Analisada a freqüência dos agentes encontrados; a maior incidência para giardiase, seguida por ascaridiase 28% dos parasitados tinham associaçöes diferentes. Os autores comentam a dificuldade na profilaxia desta infestaçöes, levando em consideraçäo a dependência da mesma no que se refere a saneamento básico, visto que a simples orientaçäo e controle se tornam ineficazes

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