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Entomopathogenic nematodes for the control of root-knot nematode Meloidogyne enterolobii
No full textNos últimos anos, tem-se estudado o uso de nematóides entomopatogênicos (NEPs) como estratégia de controle de nematoides parasitas de plantas. No entanto, são necessários estudos que comprovem em quais fases do desenvolvimento dos nematoides fitoparasitas ocorre o efeito dos NEPs e os mecanismos envolvidos. Para verificar a influência Steinernema brazilense IBCB 06, S. feltiae (Filipjev) IBCB 47, S. rarum (Doucet) IB (Rhabditida: Steinernematidae), Heterorhabditis amazonensis IBCB 24 e H. bacteriophora (Poinar) IB (Rhabditida: Heterorhabditidae) na eclosão do fitonematoide M. enterolobii, 500 ovos e 1.000 juvenis infectantes de cada espécie de nematoide entomopatogênico foram colocados em um recipiente de plástico totalizando 25 mL de suspensão e mantidos em câmara incubadora a 25ºC. O número de juvenis eclodido na suspensão foi contado a cada dois dias totalizando 10 dias. Para contagem, foi retirado um mL de suspensão e o nematoide contado na câmara de Peters sob microscópio de luz. Para avaliar o efeito dos NEPs sobre a mortalidade de juvenis infectantes de M. enterolobii, 500 juvenis infectantes de e 1.000 juvenis de cada espécie de nematoide entomopatogênico foram colocados em um recipiente de plástico totalizando 25 mL de suspensão. A mortalidade foi avaliada a cada dois dias por um tempo de 10 dias. A avaliação da mortalidade de M. enterolobii foi realizada pela contagem dos nematoides móveis e imóveis adicionando-se duas gotas de NaOH 1N à suspensão de nematoides. A contagem foi feita logo a seguir, considerando-se mortos os nematoides retos e imóveis, e, vivos, os retorcidos. Os experimentos foram conduzidos em delineamento experimental inteiramente casualizados, em esquema de parcelas subdivididas no tempo, com seis repetições. Os dados foram submetidos à análise de variância, comparando-se as médias pelo teste Scott-Knott a 5% de probabilidade no programa R Development Core Team. Para avaliar o efeito dos NEPs sobre a infecção por M. enterolobii, mudas de tomateiro foram inoculadas com 500 ovos e juvenis infectantes de M. enterolobii e 0 (somente água), 100, 500, 1.000 e 5.000 juvenis de NEPs por vaso. Sessenta dias após a inoculação, o sistema radicular de cada planta foi lavado em água corrente e submetido à coloração com Floxina B para a obtenção dos índices de galhas (IG) e índices de massas de ovos (IMO). Além disso, o sistema radicular foi pesado e cortado em pedaços pequenos para extração dos ovos. O número total de ovos e juvenis de M. enterolobii por sistema radicular foi quantificado com o auxílio de um microscópio de luz e lâminas de Peters e posteriormente calculado o fator de reprodução. Os experimentos foram conduzidos em delineamento experimental inteiramente casualizados, em esquema de fatorial duplo, com seis repetições. Os dados foram submetidos à análise de variância, comparando-se as médias pelo teste de Tukey a 5% de probabilidade no programa R Development Core Team. Os resultados demonstraram que a utilização dos nematoides entomopatogênicos testados S. brazilense, S. feltiae, S. rarum, H. amazonensis e H. bacteriophora afetam a eclosão de M. enterolobii, proporcionando menor número de juvenis eclodidos. De forma geral os NEPs S. brazilense e S. rarum proporcionaram mortalidade no segundo dia após a instalação do experimento e H. bacteriophora afetou a mortalidade dos juvenis no 4º dia. Nas demais avaliações, não houve diferença estatística. Além disso, todos os NEPs proporcionaram redução do número de galhas, massa de ovos, número total de nematoides e fator de reprodução na concentração de 5.000 juvenis por vaso. Entretanto, S. feltiae em baixas concentrações (100 juvenis por vaso) se destaca por proporcionar redução nos mesmos parâmetros metodológicos avaliados. Os resultados obtidos demonstram o potencial da utilização de NEPs em programas de manejo integrado de M. enterolobii.In recent years, the use of entomopathogenic nematodes (EPNs) has been studied as a strategy to control plant parasitic nematodes. However, studies are needed to prove in which phases of development of plant-parasitic-nematodes occurs the effect of EPNs and the mechanisms involved. To verify the influence of Steinernema brazilense IBCB 06, S. feltiae (Filipjev) IBCB 47, S. rarum (Doucet) IB (Rhabditida: Steinernematidae), Heterorhabditis amazonensis IBCB 24 e H. bacteriophora (Poinar) IB (Rhabditida: Heterorhabditidae) in the hatching of M. enterolobii, 500 eggs and 1.000 infective juveniles of each entomopathogenic nematode species were placed in a plastic container totaling 25 ml of suspension and kept in an incubator chamber at 25 °C. The number of juveniles hatched in the suspension was counted every two days totaling 10 days. For counting, one mL of suspension was withdrawn and the nematode counted in a Peters's chamber under light microscope. To evaluate the effect of EPNs on the mortality of M. enterolobii infective juveniles, 500 juvenile infective of 1000 juveniles of each entomopathogenic nematode species were placed in a plastic container totaling 25 mL of suspension. Mortality was assessed every two days for a time of 10 days. The evaluation of M. enterolobii mortality was performed by counting the mobile and immobile nematodes by adding two drops of 1N NaOH to the nematode suspension followed by counting, considering the dead straight and immobile nematodes, and, alive, the twisted ones. The experiments were conducted in a completely randomized experimental design, in a subdivided plots scheme with six replications. The data were submitted to analysis of variance, comparing the means by the Scott-Knott test to 5% probability in the R Development Core Team program.To evaluate the effect of EPNs on M. enterolobii infection, tomato seedlings were inoculated with 500 eggs and infective juveniles of M. enterolobii and 0 (water only), 100, 500, 1,000 and 5,000 juveniles of EPNs per pot. Sixty days after inoculation, the root system of each plant was washed in running water and subjected to floxin B staining to obtain gall indexes (GI) and egg mass indexes (IMO). In addition, the root system was weighed and cut into small pieces for egg extraction. The total number of eggs and juveniles of M. enterolobii by root system was quantified with the aid of a light microscope and Peters' slides and then the reproduction factor was calculated. The experiments were conducted in a completely randomized experimental design with a double factorial scheme with six replications. The data were submitted to analysis of variance, comparing the means by the Tukey test at 5% probability in the R Development Core Team program. The results showed that the use of the entomopathogenic nematodes tested S. brazilense, S. feltiae, S. rarum, H. amazonensis and H. bacteriophora affect the hatching of M. enterolobii, providing a smaller number of juvenile hatchlings. In general, EPNs S. brazilense and S. rarum provided mortality on the second day after the experiment, and H. bacteriophora affected juvenile mortality on the 4th day. In the other evaluations, there was no statistical difference. In addition, all EPNs reduced the number of galls, egg mass, total number of nematodes and reproduction factor at the concentration of 5.000 juveniles per pot. However, S. feltiae at low concentrations (100 juveniles per vessel) is notable for providing reduction in the same methodological parameters evaluated. The results demonstrate the potential of the use of EPNs in integrated management programs of M. enterolobii.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES
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No full textOlericulture is an excellent option for family farming. However, the cultivation of vegetables has gone through difficulties such as water deficit, shortage of labor and high incidence of pests, especially Spodoptera eridania. Different management methods for this pest are studied to expand the existing options. Much of the management is carried out by synthetic insecticides, but there are few products registered for crops, in addition to having low efficiency. Therefore, it is of great importance to study alternatives that reduce the use of pesticides in pest management. The objective of this research was to evaluate the efficiency and selectivity of eucalyptus (Eucalyptus citriodora) oils, rosemary (Rosmarinus officinalis), sage (Salvia sclarea), sweet basil (Ocimum basilicum), citronella (Cymbopogon winterianus), neem (Azadirachta indica), ginger (Zingiber officinale), soursop (Annona muricata) and the isolated compounds eugenol and d-limonene, as an alternative management strategy for S. eridania through studies evaluating the (1) efficiency of essential oils, fixed oils and isolated compounds in the management of Spodoptera eridania; (2) compatibility of Hetorhabditis amazonensis and Steinernema rarum with essential oils, fixed and isolated compounds; (3) selectivity of essential oils, fixed and isolated compounds to Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae); (4) efficiency of the new nucleopolyhedrovirus isolate in the management of Spodoptera eridania. From the results obtained, it was verified that: (1) the use of essential oils, fixed and isolated compounds are promising in the management of S. eridania, with emphasis on eugenol and d-limonene compounds; (2) all tested oils reduce the efficiency of H. amazonensis and S. rarum. However, in the infectivity of the juvenile, the major compound d-limonene was considered non-toxic to H. amazonensis and S. rarum, soursop oil as nontoxic to H. amazonensis and rosemary oil as non-toxic to S. rarum, according to the classification IOBC toxicology; (3) in the action of isolated oils and compounds on the parasitism of T. pretiosum, all oils and compounds tested reduced the longevity of females, and Anagasta kuehniella eggs treated with the isolated compound eugenol and the oils of O. basilicum, E. citriodora, Z. officinale, S. sclarea, R. officinalis and C. winterianus were not parasitized by females of T. pretiosum and consequently there was no emergence of individuals in these treatments; and, (4) a new isolate of S. eridania baculovirus was identified (Spodoptera eridania nucleopolyhedrovirus Se04), presenting itself as lethal for S. eridania larvae.A olericultura é uma excelente opção para agricultura familiar. No entanto, o cultivo de olerícolas tem passado por dificuldades como déficit hídrico, escassez de mão-de-obra e alta incidência de pragas, destacando-se Spodoptera eridania. Diferentes métodos de manejo dessa praga são estudados para ampliar as opções existentes. Grande parte do manejo é realizado por inseticidas sintéticos, porém existem poucos produtos registrados para as culturas, além de apresentarem baixa eficiência. Sendo assim, é de grande importância o estudo de alternativas que reduzam o uso de agrotóxicos no manejo de pragas. O objetivo dessa pesquisa foi avaliar a eficiência e seletividade dos óleos de eucalipto (Eucalyptus citriodora) alecrim (Rosmarinus officinalis), sálvia (Salvia sclarea), manjericão doce (Ocimum basilicum), citronela (Cymbopogon winterianus), neem (Azadirachta indica), gengibre (Zingiber officinale), graviola (Annona muricata) e dos compostos isolados eugenol e d-limoneno, como estratégia alternativa de manejo de S. eridania através de estudos avaliando a (1) eficiência de óleos essenciais, fixos e compostos isolados no manejo de Spodoptera eridania; (2) compatibilidade de Hetorhabditis amazonensis e Steinernema rarum com óleos essenciais, fixos e compostos isolados; (3) seletividade de óleos essenciais, fixos e compostos isolados a Trichogramma pretiosum Riley, 1879 (Hymenoptera: Trichogrammatidae); (4) eficiência do novo isolado nucleopolyhedrovirus no manejo de Spodoptera eridania. A partir dos resultados obtidos, verificou-se que: (1) o uso de óleos essenciais, fixos e compostos isolados são eficientes no manejo de S. eridania, com ênfase nos compostos eugenol e d-limoneno; (2) todos os óleos testados reduzem a eficiência de H. amazonensis e S. rarum. Porém, na infectividade do juvenil, o composto majoritário d-limoneno foi considerado não tóxico para H. amazonensis e S. rarum, óleo de graviola como não tóxico para H. amazonensis e óleo de alecrim como não tóxico para S. rarum, pela classificação toxicológica da IOBC; (3) na ação de óleos e compostos isolados sobre o parasitismo de T. pretiosum, todos os óleos e compostos testados reduzem a longevidade de fêmeas, sendo que ovos de Anagasta kuehniella tratados com o composto isolado eugenol e os óleos de O. basilicum, E. citriodora, Z. officinale, S. sclarea, R. officinalis e C. winterianus não foram parasitados por fêmeas de T. pretiosum e consequentemente não houve emergência de indivíduos nesses tratamentos; e, (4) um novo isolado de baculovírus de S. eridania foi identificado (Spodoptera eridania nucleopolyhedrovirus Se04), apresentando-se como letal para larvas de S. eridania
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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