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Identifikasi Bakteri Endofit Isolat Biogen CC-E76 dengan Teknik 16S rRNA
No full textEndophytic bacteria is bacteria, which is capable to symbiosis with other organisms mutualistically to fulfill nutrition needs. Endophytic bacteria is useful in the fields of agriculture, associated with resistance to pathogens or the ability to form a metabolite that can be transported to each other on endophytic bacteria and plant tissues. One of the endophytic bacterial isolate that successfully collected was Biogen CC-E76 isolate. Strain determination of the endophytic bacteria hasn’t been done. The purpose of this research was to identify endophytic bacteria strain by using 16S rRNA PCR technique, the identifying technique depended on the degree of sequence homology of the small subunit RNA size 16S in diverse bacteria. DNA sequence alignment result (blast) showed that the Biogen CC-E76 isolate is a strain of the bacterium Burkholderia sp. bB24 with homology level of 97%
Performance of Three Genera of Entomopathogenic Fungi as Potential Microbial Control Agents Against the Flea Beetle Phyllotreta Striolata F. (Coleoptera : Chrysomelidae)
Full text linkThe striped flea beetle (FB), Phyllotreta striolata F. (Coleoptera: Chrysomelidae), is not
only a serious pest of canoia and mustard but also feed on a wide range of other
brassicas. Entomopathogenic fungi (EF) are promising agent for biological control of
FB and are gaining increasing attention worldwide as mycoinsecticide. The potential of
three genera of EF, Metarhizium anisopliae, Beauveria bassiana and Paecilomyces
fumosoroseus, has been studied in the laboratory and the field against the striped FB,
Phyllotreta strio/ata F.
Surveys for FB naturally infected with EF indicated that M anisopliae v. manus and B.
bassiana were the potential EF in the populations of FB sampled from vegetable area at
UPM's Research Park, Serdang. However, the incidence of infection was very low.
Therefore, introduction of virulent isolates into a temporary habitat must be done. Test for pathogenicity of 16 isolates ofEF against adult FB found only one isolate of M
anisopliae (MPs) causing mortality in excess of 50%. Four isolates were tested for
pathogenicity against the eggs and larvae of the FB. Two isolates of M anisopliae (MPs
and Cy3), one B. bassiana (WIs) and one P. fumosoroseus (Pt) were found to be highly
pathogenic against the FB larvae while both isolates of M anisopliae were infective
against the FB eggs.
The resistance of FB adults against EF was caused by the existence of fungistatic
compounds on the integument. Five straight chain fatty acids (C4, C6, C7, C8, and C9)\ud
suspected as fungistatic compounds based on analysis using Gas Chromatography were
proven to inhibit conidial germination.
Two media, rice flour and sponge-rice flour medium, examined for conidial massproduction
of M anisopliae v. majus and P. fumosoroseus indicated that the spongerice
flour medium was shown to be potentially efficient for mass-production of fungal
spores
Pathogenicity of Paecilomyces fumosaroseus (Wise) Brown & Smith, Beauveria bassiana (Bals.) Vuill. and Metarhizium anisopliae (Metsch.) sorokin on the striped flea beetle Phyllotreta striolata F. (Coleoptera: Chrysomelidae)
Full text linkThe ability of three species of entomopathogenic fungi, Paecilomyces fumosoroseus (Wise) Brown & Smith, Beauveria bassiana (Bals.) Vuill. and Metarhizium anisopliae (Metsch.) Sorokin to cause infection on the adults, eggs and larvae of the striped flea beetle Phyllotreta striolata F. was tested. Only one isolate of M. anisopliae and none of the B. bassiana and P. fumosoroseus caused adult mortality in excess of 50% at a concentration of 2 x 107 conidia mL1. One isolate of?, fumosoroseus (Pf), one B. bassiana (Wls) and two of M. anisopliae (MPs and Cy3) were pathogenic to the first instar larvae of P. striolata causing more than 50% mortality at a concentration of 2 x 106 conidia mL1. The rate of larval mortality increased with increase in conidia concentration. The respective estimated LT50 values for Pf, Wls, MPs and Cy3 for the larvae at 2 x 106 conidia mL1 were2.9, 3.5, 3.0 and 3.0 days. The two isolates of M. anisopliae were also highly pathogenic to the eggs causing significant inhibition of hatching, while B. bassiana and P. fumosoroseus were less pathogenic. Estimates of the median lethal concentration for Cy3 and MPs were 13.0 x 105 and 5.03 x 105 conidia mL1 respectively
Kloning Gen β-1,4 Glukanase dari Burkholderia cepaciake dalam Escherichia coli dan Karakterisasi Sekuennya
Full text linkThe increasing of rice plant production has to deal with some constraints caused by pathogen infection such as by bacteria, viruses or fungi. Endophytic bacteria have antagonistic capacity against fungi and was used to prevent the invasion of the pathogen. Burkholderia cepacia is one of the endophytic bacteria carrying genes expressed in defense system against fungi by producing glucanase enzyme. The aim of this research was to clone a gene encoding β-1,4-glucanase from B. cepacia into the expression system in Escherichia coli. The clone of glucanase gene was isolated by PCR technique using DNA fragment of B. cepacia from rice plants. The Glu 1320 primer pairs were designed based on the glucanase gene nucleotide sequence on online database, with the length of the amplicon DNA of 1300 bp. Results from BlastN and BlastX analysis showed that the DNA fragment which was cloned into pGEM-T Easy vector had similarity with Endo-1,4-D-glucanase gene of Burkholderia mallei and Burkholderia pseudomallei. The identity of the cloned DNA fragment was 99% and E-value 0.0. Proteomic analysis of the amino acid sequence was done using Server Expasy Proteomic and the total of amino acid was 451 with, molecular weight of 48.363 kDa and isoelectric point (pI) of 5.87. The signal peptide had cleavage sites on position 23 and 24 in amino acid AAAAE. Recombinant protein clone was obtained from Protein Data Bank (PDB) database with the code of 4q2b.2.A. The protein consist of 349 residu which formed the secondary structure like of 7 betahairpin pairs, 20 turn, 3 helix-3/10, and 17 alpha-helix
Konjugat Poliklonal Antibodi Nanopartikel Emas untuk Deteksi Potato Virus Y
Full text linkPolyclonal Antibodi-Gold Nanoparticles for Potato Virus Y Detection
Gold nanoparticles are stable colloidal solutions with dimensions of 1-100 nm having surface plasmon resonance with six free electrons. The existing of six free electrons on the surface of a plasmon causes gold nanoparticles to bind easily to various types of bioreseptors including polyclonal antibodies. Polyclonal potato virus Y (PVP) antibodi been successfully conjugate with gold nanoparticles in order to develop a rapid detection for PVY infection in potato plants. The gold nanoparticles was synthetized by the reduction of gold (III) chloride trihydrate (HAuCl4) with 1% sodium citrate. Subsequently, the nanoparticles were used to make gold nanoparticle-antiobody PVY-conjugate. PVY detection was carried out with dot blot method on the nitrocellulose membrane. The results showed that the PVY virus on the membrane can be detected 10-30 minutes after incubation, depend on the concentration of the conjugate and the concentration of the virus in the sampel. The use of gold nanoparticle conjugates can increase the efficiency of the immunodot blot method in about 1 hour, and this method can be developed to be a lateral flow system for field detection of PVY.Polyclonal Antibodi-Gold Nanoparticles for Potato Virus Y Detection
Gold nanoparticles are stable colloidal solutions with dimensions of 1-100 nm having surface plasmon resonance with six free electrons. The existing of six free electrons on the surface of a plasmon causes gold nanoparticles to bind easily to various types of bioreseptors including polyclonal antibodies. Polyclonal potato virus Y (PVP) antibodi been successfully conjugate with gold nanoparticles in order to develop a rapid detection for PVY infection in potato plants. The gold nanoparticles was synthetized by the reduction of gold (III) chloride trihydrate (HAuCl4) with 1% sodium citrate. Subsequently, the nanoparticles were used to make gold nanoparticle-antiobody PVY-conjugate. PVY detection was carried out with dot blot method on the nitrocellulose membrane. The results showed that the PVY virus on the membrane can be detected 10-30 minutes after incubation, depend on the concentration of the conjugate and the concentration of the virus in the sampel. The use of gold nanoparticle conjugates can increase the efficiency of the immunodot blot method in about 1 hour, and this method can be developed to be a lateral flow system for field detection of PVY
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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
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