248 research outputs found

    Nymphal development of Podisus nigrispinus (Heteroptera, Pentatomidae) preying on larvae of Anticarsia gemmatalis (Lepidoptera, Noctuidae) fed with resistant and susceptible soybeans.

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    Nymphal development of the predator Podisus nigrispinus (Dallas) fed with a susceptible (UFV 16) or an insect resistant soybean genotype (IAC 17) and with larvae of the prey Anticarsia gemmatalis Hubner (Lepidoptera, Noctuidae) reared on these genotypes, was evaluated. Survival and duration of each instar and of total nymphal stage, besides weight of nymphs at the beginning of each instar and of adults of P. nigrispinus soon after emergence, were also evaluated. Nymphal survival of this predator was similar with both genotypes (64.41% for the UFV 16 and 72.88% for the IAC 17). Duration of second and fourth instars for nymphs that originated females, of fourth instar for those that originated males, of the nymphal period for males (20.21 and 17.94 days) and females (19.76 and 18.19 days) was longer on the IAC 17 than on the UFV 16. Weight of third instar nymphs (3.12 mg and 2.42 mg) for those that originated males and of fifth instar (26.20 mg and 23.86 mg) for those that originated females weight after emergence (65.76 mg and 58.68 mg) was lower with the IAC 17 than with the UFV 16. Sex ratio of P. nigrispinus was not affected by the resistant soybean IAC 17

    Parasitism by Campoletis flavicincta on Spodoptera frugiperda in corn.

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    ABSTRACT: Parasitism by Campoletis flavicincta (Ashmead) (Hymenoptera: Ichneumonidae) on Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) and consequent reduction of production losses were evaluated on caged corn plants in the field. Treatments consisted of plots infested with 0 (control), 15 and 30 pairs of C. flavicincta with egg masses per cage and plot infested without cage and liberation of the parasitoid. Parasitoid release was done when S. frugiperda larvae were three-day-old. Fifty corn plants (40%) per plot were collected seven days after infestation and S. frugiperda larvae present were reared in glass cups on an artificial diet. Number of S. frugiperda larvae was reduced by C. flavicincta but mortality of the pest and parasitoid sex ratio in laboratory were similar among treatments. Total progeny and female production from collected larvae were similar among densities of released parasitoid. Parasitism rate was higher on 30 than on 15 pairs of C. flavicincta. Damage on corn plants at seven and 14 days after S. frugiperda infestation had similar grades at 0, 15 or 30 C. flavicincta pairs and higher values than the plots without cage. Damage by S. frugiperda was lower at 30 C. flavicincta pairs after 21 days of infestation. Final stand, stand reduction by plant death and corn productivity were similar among treatments RESUMO: O objetivo deste trabalho foi avaliar o potencial do parasitĂłide Campoletis flavicincta (Ashmead) (Hymenoptera: Ichneumonidae) no controle de Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae) em plantas de milho protegidas por gaiolas no campo. Os tratamentos consistiram de parcelas infectadas com 0 (controle), 15 e 30 casais de C. flavicincta liberados por gaiola e parcela infestada, alĂ©m de parcelas sem gaiola e sem liberação do parasitĂłide. C. flavicincta foi liberado quando as larvas de S. frugiperda estavam com trĂȘs dias de idade. Em cada parcela, 40% das plantas foram colhidas sete dias apĂłs a infestação, e as larvas de S. frugiperda presentes foram transferidas para copos com dieta artificial. C. flavicincta reduziu o nĂșmero de larvas, mas a mortalidade natural das larvas e a razĂŁo sexual do parasitĂłide emergido em laboratĂłrio foram semelhantes entre tratamentos. A produção de progĂȘnie e de progĂȘnie fĂȘmea por C. flavicincta foi semelhante nas amostras de 15 e 30 casais, mas a taxa de parasitismo foi maior nas amostras de 30 casais do que nas de 15. Os danos Ă s plantas por larvas de S. frugiperda, aos sete e 14 dias apĂłs a infestação, foram semelhantes entre as parcelas com 0, 15 ou 30 casais de C. flavicincta, maiores do que nas parcelas sem gaiola. Esses danos foram menores nas parcelas de 30 casais do parasitĂłide, apĂłs 21 dias da infestação. O estande final, redução no estande pela morte das plantas e a produtividade do milho foram semelhantes entre tratamentos

    Proposal for a Performance Dashboard for the Monitoringof Water and Sewage Service Companies (WaSCs)

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    The water and sewage industry provides an essential service to the community, but it is characterized by natural monopoly tendencies of service suppliers. In this framework, it is very important to assist regulators with a small set of critical indicators (performance dashboard) for the evaluation and monitoring of the service provided by Water and Sewage Companies (WaSCs). The paper originates from the analysis of situation of Piemonte (Italy), where each regional and local body adopts a proprietary Performance Measurement System (PMS). In order to improve the coordination of information flow and to support the definition of common service standards, a methodology to merge existing PMSs and define a unique shared reference system is proposed. The Kaplan and Norton's Balanced Scorecard (BSC) is adopted as the reference model of this approach. BSC is widely recognized to be an exhaustive and balanced framework in describing the performances of an organization and ensures that all the operational aspects of WaSCs are adequately monitored. The output of the proposed procedure is a general performance dashboard for the monitoring of WaSCs. The dashboard is shown and some remarks about indicators properties are developed. In particular, this analysis highlights some common pitfalls originated by a ‘rushed' aggregation of several performance indicators. Description is supported by several example

    Produção de sementes de forrageiras tropicais no Brasil.

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    bitstream/item/219660/1/Boletim-CiCarne-35.pdfBoletim Cicarn

    Variação geogrĂĄfica das ĂĄreas de pastagem no Brasil nas Ășltimas dĂ©cadas.

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    bitstream/item/219658/1/Boletim-CiCarne-33.pd

    Variação geogrĂĄfica das ĂĄreas de pastagem no Brasil nas Ășltimas dĂ©cadas.

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    bitstream/item/219461/1/Boletim-CiCarne-Variacao-geografica.pdfBoletim Cicarne

    Functional and numerical responses and reproduction of Campoletis flavicincta parasitizing Spodoptera frugiperda caterpillars.

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    The functional and numerical responses, reproductive characteristics, and viability of Campoletis flavicincta (Hymenoptera: Ichneumonidae) as well as the mortality after parasitism of the host Spodoptera frugiperda (Lepidoptera: Noctuidae) were analyzed in the laboratory. Campoletis flavicincta pairs were maintained until female death with 10, 20, 30, 40, or 50 caterpillars day -1 of the host S. frugiperda. A type III functional response curve was fitted to the average number of caterpillars supplied per day during the female wasp lifespan, as the explanatory variable. The handling time was 0.5940 0.0875h, and the instantaneous search 0.0047 0.0020 h-1. The functional response for each of the first five days of the host was a type III. The longevity at the five host densities and the parasitism rate showed a significant linear decrease with the host density. The offspring production showed an increasing quadratic variation with increased host density. The production of females by C. flavicincta, the offspring sex ratio, the viability of the parasitoid pupae and the percentage of mortality of S. frugiperda caterpillars were not affected by host density. The function al and numerical responses of C. flavicincta indicate that this parasitoid could be a candidate for biological control of S. frugiperda
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