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Field and laboratory evaluations of different botanical insecticides for the control of Dactylopius opuntiae (Cockerell) on cactus pear in Morocco
No full textThe prickly-pear cactus Opuntia ficus-indica L. is grown throughout Morocco and has an important economic role as a source of food, animal feed and income for rural populations. However, currently this crop is suffering from attack by the wild cochineal Dactylopius opuntiae, which has caused huge production losses. This study was conducted to evaluate the effectiveness of five botanical extracts and a detergent for the control of nymphs and adult females of D. opuntiae in laboratory bioassays and field conditions. Under laboratory conditions, the detergent black soap at 60 g/l caused 100% mortality of D. opuntiae adult females and nymphs, 48 h after treatment. Capsicum annuum fruit extract at 10% gave 100% mortality of nymphs at 96 h after application and 56% mortality of adult females at 192 h after treatment. Under field conditions, black soap at 60 g/l applied in combination with C. annuum at 200 g/l caused the highest mortality on adult females (87.31%) at 168 h after application, and 84.9% on nymphs at 72 h after treatment. The black soap at 60 g/l had the greatest impact on mortality of D. opuntiae nymphs and adult females when applied at low to medium levels of D. opuntiae infestation. The double application of black soap at 60 g/l over a 3-day spray interval significantly increased the mortality of adult females up to 82.5% at 3 days after the second application. These findings showed that the use of the biodegradable products, black soap at 60 g/l in double application or in combination with C. annuum extract at 200 g/l, could be incorporated in the management package for the control of D. opuntiae as a safe alternative to chemical insecticides
Entomopathogenic fungi as biological control agents of Dactylopius opuntiae (Hemiptera: Dactylopiidae) under laboratory and greenhouse conditions
No full textThe cactus Opuntia ficus-indica L. is widly cultivated in Morocco and has a very an important economic role as a source of food, livestock feed and not forgetting that it is considered to be an income for people in rural communities. This crop is subject to the attack of a serious insect pest, the Dactylopius opuntiae (Cockerell), which sucks the sap from the plant causing huge production losses since its introduction to the country in 2014. The present study investigated the entomopathogenic effect of six fungal isolates {Beauveria bassiana [HASS; RFSL10; SPT 011(a)]; Akanthomyces lecanii [RFSLV; SPT R 215] and Cordyceps farinosa [SPSBI4]} for controlling of both nymphs and adult females of D. opuntiae in laboratory and greenhouse bioassays. Under laboratory conditions, the highest mortality of female D. opuntiae was registered by B. bassiana strain HASS at 108 conidia ml−1 with 100%, followed by B. bassiana strain RFSL10, A. lecanii RFSLV, and C. farinosa SPSBI4 isolates with 98%, respectively, 10 days after treatments. Similarly, the highest level of nymph mortality (100%) was recorded by B. bassiana RFSL10 and HASS isolates at 108 conidia ml1, respectively, 4 and 5 days after application. Under greenhouse conditions, B. bassiana (HASS and RFSL10) and A. lecanii (RFSLV) isolates sprayed alone expressed a higher toxicity on nymphs with 75, 68.5 and 58%, respectively, 12 days after treatments. However, no significant difference was observed in adult female's mortality between different fungal isolates, where B. bassiana (HASS) at 108 conidia ml−1 presented a moderate mortality rate with 55%, 12 days after application. In fact, the combination of black soap (60 g/L) with B. bassiana HASS and RFSL10 and A. lecanii (RFSLV) isolates at 108 conidia ml−1 caused the highest toxic activity on D. opuntiae adult females, with 70.5, 68.75 and 67.65%, respectively. These findings showed that entomopathogenic fungi are promising for developing a biopesticide formulation for the management of D. opuntiae as an adequate and safe alternative to chemical pesticides
Chemical Composition and Insecticidal Potential of Six Essential Oils from Morocco against Dactylopius opuntiae (Cockerell) under Field and Laboratory Conditions
No full textThe prickly pear Opuntia ficus-indica L. has an important economic role as a
source of food for human consumption, for cosmetic and pharmaceutical purposes, and as fodder
for livestock in Morocco. This crop is now attacked by a new sap-sucking insect pest, the wild-scale
Dactylopius opuntiae (Cockerell). The aim of this study was to investigate the insecticidal potential of
essential oils as alternative to synthetic insecticides for the control of D. opuntiae nymphs and adult
females under laboratory and field conditions. Results revealed that Mentha pulegium and Origanum
vulgare oils provided a rich source of bioactive compounds and exhibited high contact toxicity against
D. opuntiae. In addition, M. pulegium and O. vulgaris oils applied in combination with black soap
induced the highest toxic activity on adult females under field conditions.
Abstract: The carmine cochineal Dactylopius opuntiae (Cockerell) is the major insect pest of the prickly-
pear cactus Opuntia ficus-indica (L.) in Morocco. The present study investigated the insecticidal
activities of six essential oils (EOs) against nymphs and adult females of D. opuntiae applied singly or
in combination with a detergent under laboratory and field conditions. Under laboratory conditions,
M. pulegium and O. vulgare L. essential oils showed a high level of insecticidal activity at 5%, with 98%
and 92% females’ mortality, respectively, 5 days after treatments. The M. pulegium and O. vulgaris
oils at 5% applied in combination with black soap at (60 g/L) induced the highest toxic activity
on adult females, 100% and 96% at 5 days after treatments, respectively. Under field conditions,
M. pulegium and O. vulgare oils at 5% in combination with black soap (60 g/L) showed the highest
adult female mortalities with 96.33 and 92.56%, respectively, 7 days after the first application. The
double application of M. pulegium oil at 5% significantly increased the mortality of adult females up
to 91%, 5 days after the second spray. GC-MS analysis revealed that the most abundant constituent
of M. pulegium and O. vulgare oils was pulegone (84.69%) and durenol (76.53%), respectively. These
findings showed that the use of M. pulegium and O. vulgare in combination with black soap or in
double sprays could be incorporated in the management package for the control of the wild cochineal
D. opuntiae, as a safe and natural alternative to chemical insecticide
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
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