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Detection of Sclerotinia sclerotiorum on soybean and common bean seeds by modified neon-s test
Get PDFThe Neon-S method has been used for detection of Sclerotinia sclerotiorum on soybean and common bean seeds since the 2010 crop season. However, this method can lead to identification of false-positives due to the presence of other fungi that change the medium pH. Thus, this study evaluated the effect of increasing incubation period on the reliability of Neon-S test in detecting S. sclerotiorum infection on soybean and common bean seeds. A randomized block design was set up with three replicates in a 3x3 factorial scheme, consisting of three detection methods (germination paper test, Neon-S, and modified Neon-S2) and three seed material (naturally infected common beans, naturally infected and artificially inoculated soybean seeds). The three methods were compared by evaluating 400 seeds per replication, after incubating them for seven days in Neon-S, for 15 days in Neon-S2, and for 30 days in germination paper, determining the presence of the fungus and of sclerotia adhered to the seeds. The data were submitted to the analysis of variance and the averages compared by the Tukey test at 5% probability. From 2008 to 2012, 637 lots were evaluated. Among the seed material, artificially inoculated soybean presented the greatest pathogen infection index. The germination paper test led to 2.8% of positive samples, contrasting 29.7% of Neon-S. The modified method Neon-S2 increased detection sensitivity of S. sclerotiorum in seed lots (31.2%); however, did not significantly differ from the Neon-S method, despite its greater averages. We concluded that detection of S. sclerotiorum by the Neon-S method can be optimized by incubation for 15 days (Neon-S2), due to the formation of sclerotia near the infect seeds which confirms the presence of the pathogen avoiding false-positive results
Detection of sclerotinia sclerotiorum in modified NEON-S medium in soybean and common beans seeds
No full textThe Neon-S method has been used for the detection of Sclerotinia sclerotiorum in soybean and
common beans since the agricultural year 2010. However, this method yields false positive
readings due to other fungi that change medium pH. Thus, this study evaluated the contribution
of increasing incubation period on the optimization of Neon-S reliability in different cultivars of
soybeans and common beans. Nine treatments were evaluated in randomized blocks design, as a
3x3 factorial, with three replications. The factors were three detection methods (paper roll, Neon-
S, and Neon S2) and three cultivars: naturally infected Pérola beans; naturally infected soybean
cultivar BRS Valiosa RR, and artificially inoculated soybean cultivar Nidera 7255 RR).
Inoculation of soybean Nidera 7255 RR was done by incubating the seeds for 72 h on PDA
where the fungus was previously grown for seven days at 25 ºC. The three methods were
compared, evaluating 400 seeds per replication, after incubation for seven days in Neon-S, for
15 days in Neon-S2, and for 30 days in paper roll, determining the presence of the fungus, and
that of sclerotia adhered to the seeds. Twenty seeds were used per plate for media Neon-S and
Neon-S2 (20 plates per replication), and 50 seeds per roll for the paper roll. Seeds were
incubated at 20 ºC in BDO chamber in darkness. The data were submitted to the analysis of
variance and the averages compared by the Tukey test at 5% probability. The interaction
between detection method and cultivar was significant at 1% probability, indicating that the best
method depends on the cultivar under study. Among the cultivars evaluated, artificially infected
soybean presented the greatest indices of pathogen infection. A comparison of seed lots analyzed
at the Plant Disease Clinic LAMIP proved greater sensibility of Neon-S in a total of 637 lots
evaluated from 2008 to 2012. In that period, the paper roll test resulted in 21.88% positive
samples, while in Neon-S 31.25% of them were positive. Another distinguishing factor among
the lots analyzed was the percentage of infected and, or, contaminated seeds, which varied from
one (0.25%) to five (1.25%). Therefore, detection of S. sclerotiorum by the Neon-S2 method can
be optimized by incubation for 15 days, considering that, in this case, the formation of sclerotia
near the infected seeds confirm the presence of the pathogen, avoiding false positive readings.
Neon-S2 method increased detection sensibility of S. sclerotiorum in seed lots analyzed in
comparison with the paper roll method; however, in comparison with Neon S method, despite its
greater average, no significant differences were observed.Mestre em AgronomiaO método de Neon-S tem sido utilizado para a detecção de Sclerotinia sclerotiorum em sementes
de soja e feijão a partir da safra de 2010. Porém, esse método possibilita a leitura de falsos
positivos devido ao aparecimento de fungos que também alteram o pH do meio. O objetivo deste
trabalho foi verificar se o aumento do período de incubação pode contribuir para otimizar a
confiabilidade do teste Neon-S em diferentes cultivares de soja e feijão. Foram avaliados nove
tratamentos em delineamento de blocos casualizados no esquema fatorial 3x3, com três
repetições, sendo três métodos de detecção: rolo de papel, Neon-S e Neon S2 e três cultivares:
Feijão Pérola infectados naturalmente; soja cultivar BRS Valiosa RR infectadas naturalmente e
soja cultivar Nidera 7255 RR inoculada artificialmente. Para a inoculação da soja Nidera 7255
RR, as sementes foram incubadas em meio de cultivo BDA por 72 h, após o cultivo do fungo por
sete dias na temperatura de 25 ºC. Os três métodos foram comparados, avaliando 400 sementes
por repetição, meio Neon-S com incubação de sete dias, Neon-S2 com incubação de quinze dias
e o rolo de papel por trinta dias, anotando-se a presença do fungo e a presença de escleródios
aderidos às sementes. No meio Neon-S e Neon-S2 foram utilizadas 20 sementes por placa (20
placas por repetição). No rolo de papel foram usadas 50 sementes por rolo. As sementes foram
incubadas 20 ºC em BOD, no escuro. Realizou-se a análise de variância dos dados e teste de
comparação de médias (Tukey 5%). A interação entre o método de detecção e a cultivar utilizada
foi significativo a 1% de probabilidade, indicando que o melhor método depende da cultivar
avaliada. Dentro das cultivares avaliadas, a soja infectada artificialmente foi a que apresentou os
maiores índices de infecção pelo patógeno. Usando os resultados de lotes de sementes,
comprovou-se a maior sensibilidade do Neon-S num montante de 637 lotes testados no período
de 2008 a 2012. Durante esse período, o teste de rolo apresentou 21,88% de amostras positivas,
enquanto que o Neon-S foi de 31,25%. Outro fator diferenciador em relação aos lotes analisados
foi a porcentagem de sementes contaminadas e ou infectadas, que variou de uma (0,25%) a cinco
(1,25%). Assim a detecção de S. sclerotiorum pelo método Neon-S2 pode ser otimizada com a
incubação por 15 dias, considerando que, neste caso, a formação de escleródios próximos às
sementes infectadas confirma a presença do patógeno e evita a leitura de falsos positivos. O
método Neon-S2 aumentou a sensibilidade de detecção de S. sclerotiorum em lotes de sementes
analisadas quando comparado ao método de rolo, porém, quando comparado com o método
Neon S, sua média foi maior, mas a diferença não foi significativa
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
Neon-S, a new medium for detection of Sclerotinia sclerotiorum on seeds
Get PDFO meio Neon, desenvolvido para verificar a viabilidade de escleródios de Sclerotinia sclerotiorum, foi modificado e denominado de Neon-S com o objetivo de detectar o patógeno em sementes. Um antibiótico de amplo espectro e uma forma do ácido 2,4 D que suportassem a autoclavagem foram incorporados ao novo meio. Verificaram-se a concentração ideal de azul de bromofenol e as melhores condições de luminosidade e temperatura para a incubação das sementes sobre este meio. Todos os novos ingredientes do meio foram adicionados antes da autoclavagem e o ajuste de pH foi dispensado. O Neon-S foi comparado com os métodos de detecção de patógenos em sementes recomendados pelo Ministério da Agricultura, Pecuária e Abastecimento. Em relação ao método do papel de filtro e do rolo de papel, o do presente trabalho foi mais rápido e eficiente, reduzindo o tempo de detecção de 37 dias para 12 dias. _________________________________________________________________________________ ABSTRACTNeon medium, originally proposed to verify the viability of sclerotia of Sclerotinia sclerotiorum, suffered modification aiming to detect the pathogen on seeds. A wide-ranged antibiotic and a form of 2,4-D acid that could withstand sterilization were incorporated in the new medium. The ideal concentration of blue bromophenol and the best light and temperature conditions for incubation of seeds on this medium were verified. All ingredients of the new medium were added before sterilization and pH adjustment was unnecessary. This medium, named Neon-S, was compared to the methods recommended for the detection pathogens on seeds by the Brazilian Ministry of Agriculture. Compared to the filter paper test and the germination paper test, the method was faster and more efficient, by reducing the detection time of the pathogen from 37 days to 12 days
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
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