scholarly journals The impact of parasitoids on diamondback moth in Europe: a life table approach

2021 ◽  
pp. 1-16
Author(s):  
Tim Haye ◽  
Tina Dancau ◽  
Andrew M. R. Bennett ◽  
Peter G. Mason
Keyword(s):  
North America ◽  
Life Table ◽  
Larval Mortality ◽  
Diamondback Moth ◽  
Western Canada ◽  
Mortality Factors ◽  
Parasitoid Species ◽  
Pupal Parasitism ◽  
Reproductive Rates ◽  
The Impact

Abstract Diamondback moth, Plutella xylostella (Linnaeus) (Lepidoptera: Plutellidae), was first recorded in North America from Europe about 150 years ago and can be a significant pest of canola in Western Canada. Because parasitism of P. xylostella in Canada is generally low, the introduction of one or more additional exotic parasitoids from Europe is being considered to increase the suppression of P. xylostella populations. Life table studies to determine the impact of parasitoids on diamondback moth populations in Europe were conducted in northwestern Switzerland in 2014–2016. Net reproductive rates were found to be less than one in seven out of eight life tables, suggesting that P. xylostella populations in Switzerland are mostly driven by immigration and recolonisation. In total, seven primary parasitoid species and one hyperparasitoid were associated with diamondback moth. Pupal parasitism by D. collaris reached up to 30%, but because generational mortality was mainly driven by abiotic mortality factors and predation of larvae, the overall contribution of pupal parasitism was low (< 6%). In regions of Canada, where P. xylostella may have increasing populations and low larval mortality, the addition of D. collaris may be a promising approach. Life table studies across Canada are necessary to determine the need for such intervention.

Host-Plant Specific Feeding Relationships and Insect Developmental Stage Modulate the Impact of Rainfall on Diamondback Moth Larvae

2019 ◽  
Author(s):  
M D Mahbubur Rahman ◽  
Myron P Zalucki ◽  
Michael J Furlong
Keyword(s):  
Host Plant ◽  
Chinese Cabbage ◽  
Host Plants ◽  
Larval Mortality ◽  
Diamondback Moth ◽  
Feeding Site ◽  
Feeding Sites ◽  
Leaf Surfaces ◽  
The Impact ◽  
Oviposition Sites

Abstract The impact of simulated rainfall on diamondback moth (DBM), Plutella xylostella (L.) (Lepidoptera: Plutellidae), larvae depends on their stage-specific feeding behavior, physical characteristics, and host plants. Neonates released at typical oviposition sites on Chinese cabbage (Brassica rapa var. pekinensis L. [Brassicales: Brassicaceae]) plants moved less (3–72 cm) and spend shorter periods (>1 h) than it has been previously reported for common cabbage (Brassica oleracea var. capitata L. [Brassicales: Brassicaceae]) (>80 cm and >3 h, respectively) before establishing feeding sites. On both host plants, larvae spent longer on the abaxial surfaces of leaves and were more likely to establish mines there than on the adaxial surfaces. On Chinese cabbage plants, ≈40% of neonates were removed when exposed to rainfall (5.6 cm/h for 3 min) within 5 min of release. Larval losses decreased rapidly as the interval between release and rainfall exposure increased and exposure to rainfall 2 h after release did not affect survival. On common cabbage plants, ≈65% of neonates were removed when exposed to rainfall within 30 min of release, losses decreased as the interval between release and rainfall exposure increased, but they decreased more slowly than on Chinese cabbage, and rainfall caused significant larval mortality up to 4 h after release. Rainfall also affected later instar larvae (susceptibility: 2nd> 3rd = 4th) but neither the susceptibility of these larvae nor that of pupae was affected by the host plant. Wet leaf surfaces disrupted movement and feeding site establishment by neonates. When dislodged from plants on to the surface of wet soil, most later stage larvae could relocate host plants, but most neonates could not.

scholarly journals Impact of the Anomalous Latent Heat Flux Over the Kuroshio Extension on Western North American Rainfall in Spring: Interannual Variation and Mechanism

2021 ◽  
Vol 8 ◽  
Author(s):  
Jingchao Long ◽  
Chunlei Liu ◽  
Zifeng Liu ◽  
Jianjun Xu
Keyword(s):  
Heat Flux ◽  
North America ◽  
Latent Heat ◽  
Latent Heat Flux ◽  
Cyclonic Circulation ◽  
Western Canada ◽  
Jet Stream ◽  
The Impact ◽  
The Kuroshio ◽  
Anomalous Cyclonic Circulation

The Kuroshio and its extension (KE) significantly influences regional climate through meridional heat transport from the tropical ocean. In this study, the observational and reanalysis datasets are used to investigate the impact of the latent heat flux (LHF) over the KE region on downstream rainfall and the underlying mechanism. The result shows a “seesaw” structure in rainfall anomaly, dominating the Western Canada and the southwestern North America with a correlation coefficient of 0.77 between the two modes. In strong LHF years, strengthened LHF favors to enhance precipitation in the Western Canada and reduce that in the southwestern North America. This is primarily associated with an anomalous cyclonic circulation over the KE region, which enhances southwesterly precipitation and latent heating in the middle troposphere. The heating excites an anomalous cyclonic circulation to its west and an anticyclonic circulation to its east, helping to reinforce the existing anomalous cyclonic circulation in turn and form a positive feedback. The conditions associated with La Niña events favor to above processes. To the upper troposphere, the deepened anomalous cyclonic circulation due to enhanced eddy activities and atmospheric baroclinic instability over the KE strengthens subtropical westerly jet stream and thereby extends eastward on the 200 hPa level. Correspondingly, an elongated zonally lower level cyclonic circulation anomaly across the North Pacific leads to a moisture convergence in the Western Canada, which is mainly resulted from the anomalous positive vorticity advection over the left side of the exit region of the jet stream. The opposite circumstance occurs in weak LHF years, presenting an opposed anomalous circulation and rainfall pattern.

scholarly journals Impact of insecticides on the efficacy of entomopathogenic nematodes against the diamondback moth Plutella xylostella (L.) (Lepidoptera: Plutellidae) on cabbage in northern Benin

2019 ◽  
Author(s):  
Brice G. Sinhouenon ◽  
Hugues Baimey ◽  
Laura Wauters ◽  
Rufin Dossou ◽  
Regis B. Ahissou ◽  
...  
Keyword(s):  
Survival Rate ◽  
Plutella Xylostella ◽  
Entomopathogenic Nematodes ◽  
Entomopathogenic Nematode ◽  
Larval Mortality ◽  
Diamondback Moth ◽  
Neem Oil ◽  
Nematode Reproduction ◽  
The Subject ◽  
The Impact

Description of the subject. The article deals with the study of compatibility of entomopathogenic nematode (EPN) species with insecticides currently used against diamondback moth (DBM) Plutella xylostella (L.) in northern Benin Objectives. The aim of this work was to determine the impact of five insecticides on the efficacy of entomopathogenic nematodes against DBM larvae. Method. Infective juveniles (IJs) of two EPN species (Steinernema sp. 83a and Heterorhabditis sonorensis KF723827) were exposed to five insecticides used against P. xylostella larvae in Djougou for 48 h. The number of surviving nematodes was used to infest DBM larvae. The experiment was carried out under laboratory and semi-field conditions. Results. The bioassays carried out in laboratory showed that the survival rate of nematodes exposed to KARATE 2.5 WG, LAMBDA SUPER 2.5EC or neem oil ranges between 95% and 98%. In the treated plots, Steinernema sp. 83a was the most virulent with the highest P. xylostella mortality (87% at 50 IJs·cm-2 after 24 h) while only 35% larval mortality was recorded for H. sonorensis applied at the same dose. Population density of nematodes which penetrated DBM larvae reached 9 ± 3I IJs·larva-1 for H. sonorensis KF723827 and 6 ± 2 IJs·larva-1 for Steinernema sp. 83a. In cadaver of DBM, nematode reproduction did not appear to be affected by the contact with insecticides. Conclusions. Based on our research, we conclude that the three insecticides did not affect EPNs efficiency and could be used in combination against DBM.

Pentecostalism and African diaspora : a case study of the Redeemed Christian Church of God (RCCG), in North America

2020 ◽  
Vol 1 (2) ◽  
pp. 77-92
Author(s):  
Rotimi Williams Omotoye
Keyword(s):  
United States ◽  
North America ◽  
United States Of America ◽  
The United States ◽  
Church Of God ◽  
Sources Of Information ◽  
Christian Church ◽  
Secondary Sources ◽  
The Impact ◽  
The Church

Pentecostalism as a new wave of Christianity became more pronounced in 1970's and beyond in Nigeria. Since then scholars of Religion, History, Sociology and Political Science have shown keen interest in the study of the Churches known as Pentecostals because of the impact they have made on the society. The Redeemed Christian Church of God (RCCG) was established by Pastor Josiah Akindayomi in Lagos,Nigeria in 1952. After his demise, he was succeeded by Pastor Adeboye Adejare Enock. The problem of study of this research was an examination of the expansion of the Redeemed Christian Church of God to North America, Caribbean and Canada. The missionary activities of the church could be regarded as a reversed mission in the propagation of Christianity by Africans in the Diaspora. The methodology adopted was historical. The primary and secondary sources of information were also germane in the research. The findings of the research indicated that the Redeemed Christian Church of God was founded in North America by Immigrants from Nigeria. Pastor Adeboye Enock Adejare had much influence on the Church within and outside the country because of his charisma. The Church has become a place of refuge for many immigrants. They are also contributing to the economy of the United States of America. However, the members of the Church were faced with some challenges, such as security scrutiny by the security agencies. In conclusion, the RCCGNA was a denomination that had been accepted and embraced by Nigerians and African immigrants in the United States of America.

scholarly journals Is there an imbalance in the supply and demand for universal accessibility knowledge? Twenty years of UAIS papers viewed through the lens of WCAG

2021 ◽  
Author(s):  
Frode Eika Sandnes
Keyword(s):  
Latin America ◽  
North America ◽  
Supply And Demand ◽  
Research Focus ◽  
Universal Accessibility ◽  
Geographical Regions ◽  
Research Profile ◽  
The Impact ◽  
Over Time

AbstractPurpose: Some universal accessibility practitioners have voiced that they experience a mismatch in the research focus and the need for knowledge within specialized problem domains. This study thus set out to identify the balance of research into the main areas of accessibility, the impact of this research, and how the research profile varies over time and across geographical regions. Method: All UAIS papers indexed in Scopus were analysed using bibliometric methods. The WCAG taxonomy of accessibility was used for the analysis, namely perceivable, operable, and understandable. Results: The results confirm the expectation that research into visual impairment has received more attention than papers addressing operable and understandable. Although papers focussing on understandable made up the smallest group, papers in this group attracted more citations. Funded research attracted fewer citations than research without funding. The breakdown of research efforts appears consistent over time and across different geographical regions. Researchers in Europe and North America have been active throughout the last two decades, while Southeast Asia, Latin America, and Middle East became active in during the last five years. There is also seemingly a growing trend of out-of-scope papers. Conclusions: Based on the findings, several recommendations are proposed to the UAIS editorial board.

scholarly journals A Link between the Hiatus in Global Warming and North American Drought

2015 ◽  
Vol 28 (9) ◽  
pp. 3834-3845 ◽  
Author(s):  
Thomas L. Delworth ◽  
Fanrong Zeng ◽  
Anthony Rosati ◽  
Gabriel A. Vecchi ◽  
Andrew T. Wittenberg
Keyword(s):  
Global Warming ◽  
North America ◽  
Surface Temperature ◽  
North American ◽  
Radiative Forcing ◽  
Tropical Pacific ◽  
Global Warming Hiatus ◽  
Warming Hiatus ◽  
The Impact ◽  
The Tropical Pacific

Abstract Portions of western North America have experienced prolonged drought over the last decade. This drought has occurred at the same time as the global warming hiatus—a decadal period with little increase in global mean surface temperature. Climate models and observational analyses are used to clarify the dual role of recent tropical Pacific changes in driving both the global warming hiatus and North American drought. When observed tropical Pacific wind stress anomalies are inserted into coupled models, the simulations produce persistent negative sea surface temperature anomalies in the eastern tropical Pacific, a hiatus in global warming, and drought over North America driven by SST-induced atmospheric circulation anomalies. In the simulations herein the tropical wind anomalies account for 92% of the simulated North American drought during the recent decade, with 8% from anthropogenic radiative forcing changes. This suggests that anthropogenic radiative forcing is not the dominant driver of the current drought, unless the wind changes themselves are driven by anthropogenic radiative forcing. The anomalous tropical winds could also originate from coupled interactions in the tropical Pacific or from forcing outside the tropical Pacific. The model experiments suggest that if the tropical winds were to return to climatological conditions, then the recent tendency toward North American drought would diminish. Alternatively, if the anomalous tropical winds were to persist, then the impact on North American drought would continue; however, the impact of the enhanced Pacific easterlies on global temperature diminishes after a decade or two due to a surface reemergence of warmer water that was initially subducted into the ocean interior.

scholarly journals A Risk-Based Strategy for Evaluating Mitigation Options for Process-Formed Compounds in Food

2016 ◽  
Vol 35 (3) ◽  
pp. 358-370 ◽  
Author(s):  
Paul Hanlon ◽  
Gregory P. Brorby ◽  
Mansi Krishan
Keyword(s):  
North America ◽  
Decision Tree ◽  
Scientific Community ◽  
Life Sciences ◽  
Technical Committee ◽  
Global Approach ◽  
Chemical Safety ◽  
The Public ◽  
The North ◽  
The Impact

Processing (eg, cooking, grinding, drying) has changed the composition of food throughout the course of human history; however, awareness of process-formed compounds, and the potential need to mitigate exposure to those compounds, is a relatively recent phenomenon. In May 2015, the North American Branch of the International Life Sciences Institute (ILSI North America) Technical Committee on Food and Chemical Safety held a workshop on the risk-based process for mitigation of process-formed compounds. This workshop aimed to gain alignment from academia, government, and industry on a risk-based process for proactively assessing the need for and benefit of mitigation of process-formed compounds, including criteria to objectively assess the impact of mitigation as well as research needed to support this process. Workshop participants provided real-time feedback on a draft framework in the form of a decision tree developed by the ILSI North America Technical Committee on Food and Chemical Safety to a panel of experts, and they discussed the importance of communicating the value of such a process to the larger scientific community and, ultimately, the public. The outcome of the workshop was a decision tree that can be used by the scientific community and could form the basis of a global approach to assessing the risks associated with mitigation of process-formed compounds.

Interactions between pupae of the pine processionary moth (Thaumetopoea pityocampa) and parasitoids in a Pinus forest

2015 ◽  
Vol 105 (5) ◽  
pp. 621-628 ◽  
Author(s):  
C.P. Bonsignore ◽  
F. Manti ◽  
E. Castiglione
Keyword(s):  
Environmental Effects ◽  
Morphological Traits ◽  
External Factors ◽  
Thaumetopoea Pityocampa ◽  
Parasitoid Species ◽  
Pine Processionary Moth ◽  
Processionary Moth ◽  
The Impact ◽  
Positive Effect ◽  
Forest Lepidoptera

AbstractParasitoids are significant enemies of many economically important insects and there is some evidence to suggest that their actions have a role in terminating the outbreaks of forest Lepidoptera populations. In this study, we examined the impact of parasitoids on the pupae of the pine processionary moth, and highlighted the presence of several parasitoid species for this developmental stage. A higher rate of parasitism was found when the pupal density in the soil was reduced, but the rate of parasitism was not influenced by pupal morphological traits or by the presence or absence of a cocoon around a pupa. Of the external factors examined, a delay in the time of descent of larvae from the trees had a positive effect on the level of parasitism. Observational data indicated that dipteran and hymenopteran were the most abundant parasitoids to emerge from moth pupae. Our study highlights the complexity of the parasitoid–host dynamics, and stresses the importance of carefully determining environmental effects on host–parasitoid relations.

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