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Leptoglossus occidentalis (Heidemann, 1910), an invasive species attacking conifers in Lebanon: Assessment of damage and preliminary laboratory control by the entomopathogen Beauveria bassiana
No full textNEW EXTRACTION METHOD OF ENTOMOPATHOGENIC NEMATODES USING THE BASIC FLOTAC AND THE MINI-FLOTAC TECHNIQUES
Full text linkThe FLOTAC basic technique is a recognised method used mainly in the veterinary field to extract parasites
from the faeces of animals found in the stomach and intestine. This study is the first application of the FLOTAC and
Mini-FLOTAC techniques to extract infective juveniles of entomopathogenic nematodes from infested Galleria
mellonella. The EPN used for this purpose was an endemic Italian nematode belonging to the Rhabitidae family
Steinernema carpocapsae. Galleria mellonella larvae were infected and extraction was performed a few days after
infection using both techniques. A comparison was then made between the two methods. The results showed that
infective juveniles could be extracted from the infected larva as early as three days after infection. The difference
between the FLOTAC basic technique and the Mini-FLOTAC technique was not significant in the extraction of
entomopathogenic nematodes. Due to its sensitivity and operating easiness the Mini-FLOTAC technique is a promising
method for the extraction of entomopathogenic nematodes. It allows faster extraction of nematodes from the
inhabited soil and insect host than the conventional White trap method
Effect of temperature on the pathogenicity of mediterranean native entomopathogenic nematodes (steinernematidae and heterorhabditidae) from natural ecosystems
Full text linkSeven strains of entomopathogenic nematodes (EPNs) belonging to three species (Steinernema feltiae, S. ichnusae and Heterorhabditis bacteriophora) naturally isolated from Mediterranean countries (Southern Italy and Lebanon) were evaluated for their potential to infest greater wax moth (Galleria mellonella) larvae at different temperatures under laboratory conditions. The laboratory bioassay was conducted at six different temperatures ranging from 10°C to 35°C. Nematode Infective Juvenile (IJs) were put in contact with G. mellonella larvae in Petri dishes and mortality rates were recorded after 72 hours. The purpose of the study was to evaluate the temperature range in which the EPNs caused larval mortality; higher mortalities were recorded at 15°C and 20°C. All species failed at lower temperatures except for S. ichnusae ItS-SAR4, which caused 7% mortality. At 35°C S. ichnusae maintained its infectious activity (24%) along with H. bacteriophora ItH-LU1 (38%); both were isolated from Italy and were more efficient at high temperatures than the remaining Lebanese isolates
SUSCEPTIBILITY OF FOUR STORED-PRODUCT INSECT PESTS TO BEAUVERIA BASSIANA AND METARHIZIUM ANISOPLIAE STRAINS
Full text linkInsect infestations are considered one of the major problems causing enormous economic losses in stored grains. Laboratory bioassays were performed to establish the mortality induced by the commercially available Beauveria bassiana strain ATCC74040 (formulated product: Naturalis®) and by Metarhizium anisopliae strain CIST8 against four stored products pests. Adults of four grain and legume pest species (Cathartus quadricollis, Callosobruchus maculatus, Sitophilus granarius, and Oryzaephilus surinamensis) were exposed in laboratory assays to three different concentrations (103, 105 and 107/mL) of each entomopathogenic fungal strain. For each insect species, fungal strain and concentration, the mortality was recorded daily over a period of 7 days. Mean survival time and final cumulative mortality were determined, and 7-day mortality curves were established. A significant effect of insect species, fungal strain, and conidial concentration was observed on the 7-day mortality curves and the final cumulative mortality. Also, the mean survival time varied significantly with the conidial concentration. In addition, a significant interaction between insect species and fungal strain was recorded for all three assessed parameters. In general, at all tested concentrations, B. bassiana strain ATCC 74040 caused higher mortality than M. anispliae strain CIST8 in all four insect species. Our results suggest that entomopathogenic fungi could be effectively used as part of an integrated pest management program for the control of legumes and grain pests. © 2022 CREA-DC, Research Centre for Plant Protection and Certification. All rights reserved
Entomopathogenic nematodes and fungi as biological control agents of xylophagous pests in agro-forestry ecosystems
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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
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