6 research outputs found

    Indoor spraying with chlorfenapyr (a pyrrole insecticide) provides residual control of pyrethroid-resistant malaria vectors in southern Benin.

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    BACKGROUND: New classes of insecticides with novel modes of action, which can provide effective and prolonged control of insecticide-resistant malaria vector populations, are urgently needed for indoor residual spraying. Such insecticides can be included in a rotation plan to manage and prevent further development of resistance in mosquito vectors of malaria. Chlorfenapyr, a novel pyrrole insecticide with a unique mode of action, is being developed as a long-lasting IRS formulation. METHODS: The efficacy of several formulations of chlorfenapyr alone and as mixtures with alpha-cypermethrin were evaluated in an experimental hut trial against wild pyrethroid-resistant Anopheles gambiae sensu lato in Cové, Benin, in an attempt to identify the most effective and long-lasting formulations for IRS. The trial lasted 12 months. A comparison was made with alpha-cypermethrin and bendiocarb formulations. CDC bottle bioassays were performed to investigate cross-resistance to chlorfenapyr in the local vector population. RESULTS: Mortality rates in World Health Organization (WHO) cylinder bioassays were  95% with bendiocarb thus confirming susceptibility to carbamates in the vector population. CDC bottle bioassays showed no cross-resistance between pyrethroids and chlorfenapyr. Overall mortality of free-flying mosquitoes entering the experimental huts over the 12-month trial was 4% with alpha-cypermethrin and 12% with bendiocarb. The chlorfenapyr solo-formulations induced significantly higher levels of mortality (38-46%) compared to the bendiocarb (12% P  80% mortality in the first month, but this declined sharply to < 20% by the third month while the mortality rates achieved with the chlorfenapyr formulations (38-46%) were persistent lasting 7-10 months. The mixtures induced significantly lower percentage mortality than chlorfenapyr-solo formulations. Wall cone bioassays only showed mortality rates that were consistent with chlorfenapyr IRS treated huts when the exposure time was increased to 2 h. CONCLUSION: Indoor residual spraying with chlorfenapyr (Sylando® 240SC) provides moderate but prolonged control of pyrethroid-resistant malaria vectors compared to pyrethroid and bendiocarb IRS. Wall cone bioassays on chlorfenapyr-treated walls required longer exposure times of 2 h than the customary 30 min indicating that WHO guidelines on residual cone bioassays need to be more insecticide-specific

    Land Governance in The Era of Rural Development in West Africa: Scientific Results and Perspectives of Debates

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    Abstract: During the last decades, with the increase of demography, urbanization, globalization and general commodification, the land value has increased and some social strata such as young people, women and the disabled become vulnerable and their control land remains almost non-existent. This situation has led to gender inequality in farmland accessibility and increase unemployed young people. With the aim to improve conditions of access to farmland, this analysis to shed light on land tenure problematic and problems related to young people and women's access to farmland. A total of 70 papers from Africa, Asia, America and Europe have been considered. In Africa, 8.1 to 15% of papers have been produced by researchers from Benin Republic and Senegal, and 6.1 to 8% from Burkina Faso, Mali and Niger. 52.73% papers from international results, when 36.36% and 10.91% have respectively been collected form other national or local scales. The main research fields of these papers are rural land acquisition and accessibility, conflicts about land accessibility, land governance and institutions, and about actors and vulnerability. Inheritance was the most common regime of land tenure in the most of the countries in Africa while the smallest land tenure scheme was the borrowing regime with 23.67%. 85% of papers identified women as the most vulnerable actors in the acquisition and accessibility of rural lands. However, youth are almost excluded from access to land ownership. This study provides an analytical overview on the difficulties of women and young people to accede to farmland that are important to increase the agricultural productivity and to improve gender inequalities in rural land acquisition and accessibility.  Keywords Land governance, access to land, rural development, land conflict. West Africa

    The Afrotropical breeding grounds of the Palearctic-African migratory painted lady butterflies (Vanessa cardui)

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    Migratory insects are key players in ecosystem functioning and services, but their spatiotemporal distributions are typically poorly known. Ecological niche modeling (ENM) may be used to predict species seasonal distributions, but the resulting hypotheses should eventually be validated by field data. The painted lady butterfly (Vanessa cardui) performs multigenerational migrations between Europe and Africa and has become a model species for insect movement ecology. While the annual migration cycle of this species is well understood for Europe and northernmost Africa, it is still unknown where most individuals spend the winter. Through ENM, we previously predicted suitable breeding grounds in the subhumid regions near the tropics between November and February. In this work, we assess the suitability of these predictions through i) extensive field surveys and ii) two-year monitoring in six countries: a large-scale monitoring scheme to study butterfly migration in Africa. We document new breeding locations, year-round phenological information, and hostplant use. Field observations were nearly always predicted with high probability by the previous ENM, and monitoring demonstrated the influence of the precipitation seasonality regime on migratory phenology. Using the updated dataset, we built a refined ENM for the Palearctic-African range of V. cardui. We confirm the relevance of the Afrotropical region and document the missing natural history pieces of the longest migratory cycle described in butterflies.This work was funded by the National Geographic Society (grant WW1-300R-18); by the British Ecological Society (grant LRB16/1015); by the Research and Conservation Projects of the Fundació Barcelona Zoo; by the grant PID2020-117739GA-I00/MCIN/AEI/10.13039/501100011033 of the Spanish Ministry of Science and Innovation and the Spanish State Research Agency to G.T.; by the grant LINKA20399 from the Spanish National Research Council iLink program to G.T., C.P.B., N.E.P., and R.V.; by fellowship FPU19/01593 of the program Formación de Profesorado Universitario (FPU) to A.G.-B.; by the Turkana Basin Institute, National Geographic Society, and Whitley Fund for Nature to D.J.M.; and by grant 2018-00738 of the New Frontiers in Research Fund (Government of Canada) to G.T. and C.P.B.Significance Abstract Results Field Surveys, Larval Hostplants, and Field-Based Model Validation Monitoring Results and Population Dynamics across Regions A Refined Model for the Afrotropical Region Discussion The Afrotropical Breeding Grounds of V. cardui: Multiple Generations Shift South Toward the Tropics Diversity and Phenology of Larval Hostplants in the Afrotropics The Ecological Relevance of Delimiting Spatiotemporal Distributions in Migratory Insects Conclusion Methods December-January Field Surveys and Year-Round Monitoring Spatiotemporal Ecological Niche Modeling Data, Materials, and Software Availability Acknowledgments Supporting Information Reference

    Bibliometric analysis and survey on electronic nose used in agriculture

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    Work carried out at the beginning of this century on improvements in semiconductor materials, transducers, sensors and artificial intelligence algorithms led to the rapid expansion of research topics related to the electronic nose, with diverse applications. Agriculture is a recent application field that needs a review of the usage of electronic noses in this field and the future challenges. The paper provided a bibliometric analysis and review of electronic noses used in agriculture. A search of published works on the e-nose and its applications in agriculture was carried out in the Web of Science and Scopus databases, which provide comprehensive citation data for academic disciplines worldwide. In the end, 2,953 documents were identified, and the data collected was analyzed mainly using the bibliometric toolbox, and then a deep study was carried out. The study results show that in the agricultural field, some works were achieved on different varieties of plants to detect disease or plant damage with very good results using electronic noses. However, less research was carried out to directly identify animals in crops like pests or environmental monitoring using electronic noses in agriculture. Some recommendations for future research efforts are finally provided

    Genetic guidelines for translocations:Maintaining intraspecific diversity in the lion (<i>Panthera leo</i>)

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    Conservation translocations have become an important management tool, particularly for large wildlife species such as the lion (Panthera leo). When planning translocations, the genetic background of populations needs to be taken into account; failure to do so risks disrupting existing patterns of genetic variation, ultimately leading to genetic homogenization, and thereby reducing resilience and adaptability of the species. We urge wildlife managers to include knowledge of the genetic background of source/target populations, as well as species‐wide patterns, in any management intervention. We present a hierarchical decision‐making tool in which we list 132 lion populations/lion conservation units and provide information on genetic assignment, uncertainty and suitability for translocation for each source/target combination. By including four levels of suitability, from ‘first choice’ to ‘no option’, we provide managers with a range of options. To illustrate the extent of international trade of lions, and the potential disruption of natural patterns of intraspecific diversity, we mined the CITES Trade Database for estimated trade quantities of live individuals imported into lion range states during the past 4 decades. We identified 1056 recorded individuals with a potential risk of interbreeding with wild lions, 772 being captive‐sourced. Scoring each of the records with our decision‐making tool illustrates that only 7% of the translocated individuals were ‘first choice’ and 73% were ‘no option’. We acknowledge that other, nongenetic factors are important in the decision‐making process, and hence a pragmatic approach is needed. A framework in which source/target populations are scored based on suitability is not only relevant to lion, but also to other species of wildlife that are frequently translocated. We hope that the presented overview supports managers to include genetics in future management decisions and contributes towards conservation of the lion in its full diversity

    Genetic guidelines for translocations : maintaining intraspecific diversity in the lion (Panthera leo)

    Get PDF
    Conservation translocations have become an important management tool, particularly for large wildlife species such as the lion (Panthera leo). When planning translocations, the genetic background of populations needs to be taken into account; failure to do so risks disrupting existing patterns of genetic variation, ultimately leading to genetic homogenization, and thereby reducing resilience and adaptability of the species. We urge wildlife managers to include knowledge of the genetic background of source/target populations, as well as species-wide patterns, in any management intervention. We present a hierarchical decision-making tool in which we list 132 lion populations/lion conservation units and provide information on genetic assignment, uncertainty and suitability for translocation for each source/target combination. By including four levels of suitability, from ‘first choice’ to ‘no option’, we provide managers with a range of options. To illustrate the extent of international trade of lions, and the potential disruption of natural patterns of intraspecific diversity, we mined the CITES Trade Database for estimated trade quantities of live individuals imported into lion range states during the past 4 decades. We identified 1056 recorded individuals with a potential risk of interbreeding with wild lions, 772 being captive-sourced. Scoring each of the records with our decision-making tool illustrates that only 7% of the translocated individuals were ‘first choice’ and 73% were ‘no option’. We acknowledge that other, nongenetic factors are important in the decision-making process, and hence a pragmatic approach is needed. A framework in which source/target populations are scored based on suitability is not only relevant to lion, but also to other species of wildlife that are frequently translocated. We hope that the presented overview supports managers to include genetics in future management decisions and contributes towards conservation of the lion in its full diversity.http://www.wileyonlinelibrary.com/journal/evahj2022Mammal Research InstituteZoology and Entomolog
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