1
|
Röder N, Stoll VS, Jupke JF, Kolbenschlag S, Bundschuh M, Theißinger K, Schwenk K. How non-target chironomid communities respond to mosquito control: Integrating DNA metabarcoding and joint species distribution modelling. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 913:169735. [PMID: 38163597 DOI: 10.1016/j.scitotenv.2023.169735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 11/26/2023] [Accepted: 12/26/2023] [Indexed: 01/03/2024]
Abstract
The conservation and management of riparian ecosystems rely on understanding the ecological consequences of anthropogenic stressors that impact natural communities. In this context, studies investigating the effects of anthropogenic stressors require reliable methods capable of mapping the relationships between taxa occurrence or abundance and environmental predictors within a spatio-temporal framework. Here, we present an integrative approach using DNA metabarcoding and Hierarchical Modelling of Species Communities (HMSC) to unravel the intricate dynamics and resilience of chironomid communities exposed to Bacillus thuringiensis var. israelensis (Bti). Chironomid emergence was sampled from a total of 12 floodplain pond mesocosms, half of which received Bti treatment, during a 16-week period spanning spring and summer of 2020. Subsequently, we determined the community compositions of chironomids and examined their genus-specific responses to the Bti treatment, considering their phylogenetic affiliations and ecological traits of the larvae. Additionally, we investigated the impact of the Bti treatment on the body size distribution of emerging chironomids. Our study revealed consistent responses to Bti among different chironomid genera, indicating that neither phylogenetic affiliations nor larval feeding strategies significantly contributed to the observed patterns. Both taxonomic and genetic diversity were positively correlated with the number of emerged individuals. Furthermore, our findings demonstrated Bti-related effects on chironomid body size distribution, which could have relevant implications for size-selective terrestrial predators. Hence, our study highlights the value of employing a combination of DNA metabarcoding and HMSC to unravel the complex dynamics of Bti-related non-target effects on chironomid communities. The insights gained from this integrated framework contribute to our understanding of the ecological consequences of anthropogenic stressors and provide a foundation for informed decision-making regarding the conservation and management of riparian ecosystems.
Collapse
Affiliation(s)
- Nina Röder
- iES - Institute for Environmental Sciences, RPTU Kaiserslautern-Landau, Landau, Germany.
| | - V Sophie Stoll
- iES - Institute for Environmental Sciences, RPTU Kaiserslautern-Landau, Landau, Germany
| | - Jonathan F Jupke
- iES - Institute for Environmental Sciences, RPTU Kaiserslautern-Landau, Landau, Germany
| | - Sara Kolbenschlag
- iES - Institute for Environmental Sciences, RPTU Kaiserslautern-Landau, Landau, Germany
| | - Mirco Bundschuh
- iES - Institute for Environmental Sciences, RPTU Kaiserslautern-Landau, Landau, Germany; Department of Aquatic Science and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - Kathrin Theißinger
- LOEWE Centre for Translational Biodiversity Genomics, Senckenberg Biodiversity and Climate Research Centre, Frankfurt am Main, Germany
| | - Klaus Schwenk
- iES - Institute for Environmental Sciences, RPTU Kaiserslautern-Landau, Landau, Germany; LOEWE Centre for Translational Biodiversity Genomics, Senckenberg Biodiversity and Climate Research Centre, Frankfurt am Main, Germany
| |
Collapse
|
2
|
Dornelas ASP, Pestana JLT, de Souza Saraiva A, Barbosa RS, Cavallini GS, Gravato C, da Maia Soares AMV, Sarmento RA. The combined effects of microbial insecticides and sodium chloride on the development and emergence of Chironomus xanthus. PEST MANAGEMENT SCIENCE 2023; 79:2255-2263. [PMID: 36775861 DOI: 10.1002/ps.7407] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/24/2021] [Revised: 01/27/2023] [Accepted: 02/13/2023] [Indexed: 05/03/2023]
Abstract
BACKGROUND Freshwater organisms are facing increasing salinity levels, not only due to natural environmental processes, but also human activities, which can cause several physiological adaptations to osmotic stress. Additionally, these organisms might also have to deal with contamination by microbial insecticides. Our main goal was to use Chironomus xanthus to assess the chronic effects of increasing the salinity and commercial formulations of the microbial insecticides based on Bacillus thuringiensis subs. kurstaki (Btk) and Beauveria bassiana (Bb) as active ingredients, respectively. RESULTS A significant interaction of growth was observed between the biopesticide based on Bb and NaCl on the larvae of C. xanthus. Single exposure to NaCl and each one of the formulations demonstrated deleterious impacts not only on larval development, but also on the emergence success and emergence time of this nontarget insect, with potential consequences for freshwater ecosystems due to cascading effects. CONCLUSION The chronic effects induced by both bioinsecticides show that these formulations can have environmental impacts on nontarget freshwater insects. © 2023 Society of Chemical Industry.
Collapse
Affiliation(s)
| | - João L T Pestana
- Departamento de Biologia & CESAM, Universidade de Aveiro, Campus de Santiago, 3810-193, Aveiro, Portugal
| | | | - Rone Silva Barbosa
- Programa de Pós-Graduação em Produção Vegetal, Campus Universitário de Gurupi, 77402-970, Gurupi, Tocantins, Brazil
| | - Grasiele Soares Cavallini
- Programa de Pós-Graduação em Produção Vegetal, Campus Universitário de Gurupi, 77402-970, Gurupi, Tocantins, Brazil
| | - Carlos Gravato
- Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016, Lisbon, Portugal
| | | | - Renato Almeida Sarmento
- Programa de Pós-Graduação em Produção Vegetal, Campus Universitário de Gurupi, 77402-970, Gurupi, Tocantins, Brazil
| |
Collapse
|
3
|
Dornelas ASP, Sarmento RA, Saraiva AS, Barbosa RS, Vieira MM, Gravato C, Soares AMVM. Effects of two biopesticides and salt on behaviour, regeneration and sexual reproduction of the freshwater planarian Girardia tigrina. JOURNAL OF HAZARDOUS MATERIALS 2021; 404:124089. [PMID: 33049628 DOI: 10.1016/j.jhazmat.2020.124089] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2020] [Revised: 09/22/2020] [Accepted: 09/22/2020] [Indexed: 06/11/2023]
Abstract
Microbial insecticides are being used as ecologically-friendly alternatives to traditional insecticides. However, their effects have been poorly investigated on non-target freshwater species, with exception of a few insect species. Moreover, combined effects of microbial insecticides with other environmental stressors, such as salinity, have never been investigated. Thus, our goal was to assess the effects of Bac-Control® (based in Bacillus thuringiensis - Btk) and Boveril® (based in Beauveria bassiana - Bb) with increasing salinities (NaCl) on freshwater planarian Girardia tigrina. It has been reported that increased salinity levels affect freshwater organisms compromising their survival by triggering adaptation processes to cope with osmotic stress. Our results showed delayed regeneration, decreased locomotion and feeding on planarians exposed to NaCl, whereas their sexual reproduction was not affected. Both microbial insecticides impaired feeding, locomotor activity, regeneration, and sexual reproduction of planarians. Planarians exposed to microbial insecticides compromised their progeny. Therefore, microbial insecticides might not be ecologically friendly alternatives to chemical insecticides. Interestingly, harmful effects of microbial insecticides with increasing salinities showed an inadequate response of planarians to cope with induction of their immune response and osmoregulation.
Collapse
Affiliation(s)
- Aline S P Dornelas
- Programa de Pós-graduação em Produção Vegetal, Universidade Federal do Tocantins, Campus Universitário de Gurupi, 77402-970 Gurupi, Tocantins, Brazil
| | - Renato A Sarmento
- Programa de Pós-graduação em Produção Vegetal, Universidade Federal do Tocantins, Campus Universitário de Gurupi, 77402-970 Gurupi, Tocantins, Brazil
| | - Althiéris S Saraiva
- Instituto Federal de Educação, Ciência e Tecnologia Goiano - Campus Campos Belos (Laboratório de Conservação de Agroecossistemas e Ecotoxicologia), Campos Belos, 73840-000 Goiás, Brazil
| | - Rone S Barbosa
- Programa de Pós-graduação em Produção Vegetal, Universidade Federal do Tocantins, Campus Universitário de Gurupi, 77402-970 Gurupi, Tocantins, Brazil
| | - Mayane M Vieira
- Curso de Química Ambiental, Universidade Federal do Tocantins, 77410-530 Gurupi, Tocantins, Brazil
| | - Carlos Gravato
- Faculdade de Ciências & CESAM, Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal
| | - Amadeu M V M Soares
- Programa de Pós-graduação em Produção Vegetal, Universidade Federal do Tocantins, Campus Universitário de Gurupi, 77402-970 Gurupi, Tocantins, Brazil; Departamento de Biologia & CESAM, Universidade de Aveiro, Campus de Santiago, 3810-193 Aveiro, Portugal.
| |
Collapse
|
4
|
Babin A, Nawrot-Esposito MP, Gallet A, Gatti JL, Poirié M. Differential side-effects of Bacillus thuringiensis bioinsecticide on non-target Drosophila flies. Sci Rep 2020; 10:16241. [PMID: 33004867 PMCID: PMC7529784 DOI: 10.1038/s41598-020-73145-6] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2019] [Accepted: 09/07/2020] [Indexed: 01/22/2023] Open
Abstract
Bioinsecticides based on Bacillus thuringiensis (Bt) spores and toxins are increasingly popular alternative solutions to control insect pests, with potential impact of their accumulation in the environment on non-target organisms. Here, we tested the effects of chronic exposure to commercial Bt formulations (Bt var. kurstaki and israelensis) on eight non-target Drosophila species present in Bt-treated areas, including D. melanogaster (four strains). Doses up to those recommended for field application (~ 106 Colony Forming Unit (CFU)/g fly medium) did not impact fly development, while no fly emerged at ≥ 1000-fold this dose. Doses between 10- to 100-fold the recommended one increased developmental time and decreased adult emergence rates in a dose-dependent manner, with species-and strain-specific effect amplitudes. Focusing on D. melanogaster, development alterations were due to instar-dependent larval mortality, and the longevity and offspring number of adult flies exposed to bioinsecticide throughout their development were moderately influenced. Our data also suggest a synergy between the formulation compounds (spores, cleaved toxins, additives) might induce the bioinsecticide effects on larval development. Although recommended doses had no impact on non-target Drosophila species, misuse or local environmental accumulation of Bt bioinsecticides could have side-effects on fly populations with potential implications for their associated communities.
Collapse
Affiliation(s)
- Aurélie Babin
- Institut Sophia Agrobiotech, Université Côte D'Azur, INRAE, CNRS, ISA, 400 route des chappes, 06903, Sophia Antipolis, France
| | - Marie-Paule Nawrot-Esposito
- Institut Sophia Agrobiotech, Université Côte D'Azur, INRAE, CNRS, ISA, 400 route des chappes, 06903, Sophia Antipolis, France
| | - Armel Gallet
- Institut Sophia Agrobiotech, Université Côte D'Azur, INRAE, CNRS, ISA, 400 route des chappes, 06903, Sophia Antipolis, France
| | - Jean-Luc Gatti
- Institut Sophia Agrobiotech, Université Côte D'Azur, INRAE, CNRS, ISA, 400 route des chappes, 06903, Sophia Antipolis, France.
| | - Marylène Poirié
- Institut Sophia Agrobiotech, Université Côte D'Azur, INRAE, CNRS, ISA, 400 route des chappes, 06903, Sophia Antipolis, France
| |
Collapse
|
5
|
Brühl CA, Després L, Frör O, Patil CD, Poulin B, Tetreau G, Allgeier S. Environmental and socioeconomic effects of mosquito control in Europe using the biocide Bacillus thuringiensis subsp. israelensis (Bti). THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 724:137800. [PMID: 32249002 DOI: 10.1016/j.scitotenv.2020.137800] [Citation(s) in RCA: 45] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2020] [Revised: 03/06/2020] [Accepted: 03/06/2020] [Indexed: 06/11/2023]
Abstract
Bacillus thuringiensis subsp. israelensis (Bti) has been used in mosquito control programs to reduce nuisance in Europe for decades and is generally considered an environmentally-safe, effective and target-specific biocide. However, the use of Bti is not uncontroversial. Target mosquitoes and affected midges represent an important food source for many aquatic and terrestrial predators and reduction of their populations is likely to result in food-web effects at higher trophic levels. In the context of global biodiversity loss, this appears particularly critical since treated wetlands are often representing conservation areas. In this review, we address the current large-scale use of Bti for mosquito nuisance control in Europe, provide a description of its regulation followed by an overview of the available evidence on the parameters that are essential to evaluate Bti use in mosquito control. Bti accumulation and toxin persistence could result in a chronic expose of mosquito populations ultimately affecting their susceptibility, although observed increase in resistance to Bti in mosquito populations is low due to the four toxins involved. A careful independent monitoring of mosquito susceptibility, using sensitive bioassays, is mandatory to detect resistance development timely. Direct Bti effects were documented for non-target chironomids and other invertebrate groups and are discussed for amphibians. Field studies revealed contrasting results on possible impacts on chironomid abundances. Indirect, food-web effects were rarely studied in the environment. Depending on study design and duration, Bti effects on higher trophic levels were demonstrated or not. Further long-term field studies are needed, especially with observations of bird declines in Bti-treated wetland areas. Socio-economic relevance of mosquito control requires considering nuisance, vector-borne diseases and environmental effects jointly. Existing studies indicate that a majority of the population is concerned regarding potential environmental effects of Bti mosquito control and that they are willing to pay for alternative, more environment-friendly techniques.
Collapse
Affiliation(s)
- Carsten A Brühl
- iES Landau, Institute for Environmental Sciences, University of Koblenz-Landau, D-76829 Landau, Germany.
| | - Laurence Després
- Université Grenoble Alpes, CNRS, Laboratoire d'Ecologie Alpine, F-38000 Grenoble, France
| | - Oliver Frör
- iES Landau, Institute for Environmental Sciences, University of Koblenz-Landau, D-76829 Landau, Germany
| | - Chandrashekhar D Patil
- Centre of Island Research and Environmental Observatory, PSL Université Paris: EPHE-UPVD-CNRS, USR 3278 CRIOBE, Université de Perpignan, F-66860 Perpignan, France
| | - Brigitte Poulin
- Tour du Valat, Research Institute for the Conservation of Mediterranean Wetlands, Le Sambuc, F-13200 Arles, France
| | | | - Stefanie Allgeier
- iES Landau, Institute for Environmental Sciences, University of Koblenz-Landau, D-76829 Landau, Germany
| |
Collapse
|
6
|
Bordalo MD, Gravato C, Beleza S, Campos D, Lopes I, Pestana JLT. Lethal and sublethal toxicity assessment of Bacillus thuringiensis var. israelensis and Beauveria bassiana based bioinsecticides to the aquatic insect Chironomus riparius. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 698:134155. [PMID: 31505347 DOI: 10.1016/j.scitotenv.2019.134155] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 08/26/2019] [Accepted: 08/26/2019] [Indexed: 06/10/2023]
Abstract
Despite being considered environmentally safe, a deeper environmental risk assessment is needed for microbial insecticides; special attention should be devoted to their sublethal toxicity to non-target species. This study evaluated effects of VectoBac® 12AS - VB (based on the bacterium Bacillus thurigiensis var. israelensis) and Naturalis®-L - NL (based on the fungus Beauveria bassiana) on the aquatic insect Chironomus riparius life-history and biochemical responses. Acute tests estimated a 48 h-LC50 (median lethal concentration) of 1.85 μg/L (VB) and 34.7 mg/L (NL). Under sublethal exposure, VB decreased adults' emergence (LOEC - lowest observed effect concentration of 80 ng/L) while NL impaired larval growth (LOEC of 0.32 mg/L) and delayed emergence (LOEC of 2 mg/L for males and 0.8 mg/L for females). Despite not being monotonic, phenoloxidase activity increased (LOEC of 20 ng/L (VB) and 2 mg/L (NL)), suggesting activation of the immune system. There were no indications of oxidative damage nor neurotoxicity. Catalase activity was stimulated with all VB treatments, possibly associated with detoxification of immune response products. Under NL exposure, glutathione-S-transferase activity increased but did not show a dose-dependent response and, total glutathione decreased in the highest concentration. Exposure to both formulations caused the increase in protein content, while carbohydrate and lipids were not altered. This study revealed the susceptibility of C. riparius to VB and NL at concentrations below the ones recommended for field application, with potential population-level effects. These results add important information for the risk assessment of these microbial insecticides in aquatic ecosystems, considering relevant sublethal endpoints and raising concern about the adverse effects on non-target aquatic organisms.
Collapse
Affiliation(s)
- M D Bordalo
- Department of Biology & CESAM, University of Aveiro, Portugal.
| | - C Gravato
- Faculty of Sciences & CESAM, University of Lisbon, Portugal
| | - S Beleza
- Faculty of Sciences & CESAM, University of Lisbon, Portugal
| | - D Campos
- Department of Biology & CESAM, University of Aveiro, Portugal
| | - I Lopes
- Department of Biology & CESAM, University of Aveiro, Portugal
| | - J L T Pestana
- Department of Biology & CESAM, University of Aveiro, Portugal
| |
Collapse
|
7
|
Schweizer M, Miksch L, Köhler HR, Triebskorn R. Does Bti (Bacillus thuringiensis var. israelensis) affect Rana temporaria tadpoles? ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 181:121-129. [PMID: 31176246 DOI: 10.1016/j.ecoenv.2019.05.080] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Revised: 05/21/2019] [Accepted: 05/30/2019] [Indexed: 06/09/2023]
Abstract
Biocides based on toxins of Bacillus thuringiensis var. israelensis (Bti) are established as alternatives to conventional chemical insecticides for mosquito control all across the globe since they are regarded ecologically compatible and harmless to non-target species. Since recent studies on amphibian larvae have called this opinion into question, we exposed Rana temporaria tadpoles to single (1 mg/L), tenfold (10 mg/L) and hundredfold (100 mg/L) field concentrations of VectoBac® WG (a water dispersible granule Bti formulation) in the laboratory for eleven days to investigate whether larvae were adversely affected by Bti and its endotoxin proteins. In addition to a negative (water) control, a positive control based on organic rice protein (50 mg/L) was run to check for the nutritional relevance of Bti proteins. There was no Bti-related mortality and a histopathological analysis of tadpole intestines revealed no adverse effects. Analyses of biomarkers for proteotoxicity (stress protein family, Hsp70) and neurotoxicity or metabolic action (b-esterases acetylcholine esterase (AChE) and carboxylesterases) revealed no significant differences between Bti treatments and the negative control. The responses of tadpoles in the protein-supplemented positive control differed from those of the negative control and the Bti treatments. Tadpoles in the positive control had reduced body mass and elevated AChE activity.
Collapse
Affiliation(s)
- Mona Schweizer
- Animal Physiological Ecology, Eberhard Karls University of Tübingen, Auf der Morgenstelle 5, 72076, Tübingen, Germany.
| | - Lukas Miksch
- Animal Physiological Ecology, Eberhard Karls University of Tübingen, Auf der Morgenstelle 5, 72076, Tübingen, Germany
| | - Heinz-R Köhler
- Animal Physiological Ecology, Eberhard Karls University of Tübingen, Auf der Morgenstelle 5, 72076, Tübingen, Germany
| | - Rita Triebskorn
- Animal Physiological Ecology, Eberhard Karls University of Tübingen, Auf der Morgenstelle 5, 72076, Tübingen, Germany; Steinbeis Transfer-Center for Ecotoxicology and Ecophysiology, Blumenstr. 13, 72108, Rottenburg am Neckar, Germany
| |
Collapse
|
8
|
Allgeier S, Kästel A, Brühl CA. Adverse effects of mosquito control using Bacillus thuringiensis var. israelensis: Reduced chironomid abundances in mesocosm, semi-field and field studies. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2019; 169:786-796. [PMID: 30597777 DOI: 10.1016/j.ecoenv.2018.11.050] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/06/2018] [Revised: 10/10/2018] [Accepted: 11/12/2018] [Indexed: 06/09/2023]
Abstract
The ecological consequences of mosquito control using the larvicide Bacillus thuringiensis israelensis (Bti) are still a matter of debate especially when it comes to adverse effects on non-target but susceptible non-biting midges (Chironomidae). Our work aimed to assess the effects of Bti applied in operational mosquito control rates on chironomid abundances in seasonal flooded freshwater wetlands. We assessed the invertebrate community alongside with aquatic insect emergence rates in studies with increasing ecotoxicological complexity, ranging from artificial mesocosms, over a semi-field approach using enclosures to natural conditions in field studies. Study sites represented different habitats (forest, meadow, floodplain) with regularly Bti treated and untreated temporal wetlands that are located in the Upper Rhine Valley, Germany. Larval chironomids were the most affected group of organism in the altered aquatic invertebrate communities of the Bti treated pond mesocosms. The larvae of the chironomid subfamilies Chironominae and Orthocladiinae were affected by Bti field concentrations while emergence rates of Tanypodinae did not change. The Bti treatment significantly reduced the targeted mosquitoes in the mesocosm and in the field studies. At the same time, however, the application of operational Bti field rates reduced overall chironomid emergence rates to about half of the control rates. The observed abundance reductions occurred independently of the ecological complexity in the study design in artificial mesocosms as well as realistic field conditions. The considerable reduction of the abundant non-target chironomids along with mosquitoes may subsequently lead to unwanted indirect negative effects for birds, bats and other aquatic organisms feeding on midges. Hence, large-scale applications of Bti for mosquito control in seasonal wetlands should be considered more carefully. This is of special importance when these wetlands are parts of national parks, nature reserves or Natura 2000 sites that were created for the protection of nature and environmental health.
Collapse
Affiliation(s)
- Stefanie Allgeier
- Institute for Environmental Sciences, University of Koblenz-Landau, Fortstraße 7, 76829 Landau, Germany.
| | - Anna Kästel
- Institute for Environmental Sciences, University of Koblenz-Landau, Fortstraße 7, 76829 Landau, Germany
| | - Carsten A Brühl
- Institute for Environmental Sciences, University of Koblenz-Landau, Fortstraße 7, 76829 Landau, Germany
| |
Collapse
|
9
|
|
10
|
Decreasing Bacillus thuringiensis israelensis sensitivity of Chironomus riparius larvae with age indicates potential environmental risk for mosquito control. Sci Rep 2017; 7:13565. [PMID: 29051576 PMCID: PMC5648803 DOI: 10.1038/s41598-017-14019-2] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2016] [Accepted: 09/25/2017] [Indexed: 11/30/2022] Open
Abstract
Mosquito control based on the use of Bacillus thuringiensis israelensis (Bti) is regarded as an environmental friendly method. However, Bti also affects non-target chironomid midges that are recognized as a central resource in wetland food webs. To evaluate the risk for different larval stages of Chironomus riparius we performed a test series of daily acute toxicity laboratory tests following OECD guideline 235 over the entire aquatic life cycle of 28 days. Our study is the first approach that performs an OECD approved test design with Bti and C. riparius as a standard organism in ecotoxicological testing. First-instar larvae of Chironomus riparius show an increased sensitivity towards Bti which is two orders of magnitude higher than for fourth instar larvae. Most EC50 values described in the literature are based on acute toxicity tests using third and fourth instar larvae. The risk for chironomids is underestimated when applying the criteria of the biocide regulation EU 528/2012 to our data and therefore the existing assessment approval is not protective. Possible impacts of Bti induced changes in chironomid abundances and community composition may additionally affect organisms at higher trophic levels, especially in spring when chironomid midges represent a key food source for reproducing vertebrates.
Collapse
|
11
|
Pruszynski CA, Hribar LJ, Mickle R, Leal AL. A Large Scale Biorational Approach Using Bacillus thuringiensis israeliensis (Strain AM65-52) for Managing Aedes aegypti Populations to Prevent Dengue, Chikungunya and Zika Transmission. PLoS One 2017; 12:e0170079. [PMID: 28199323 PMCID: PMC5310849 DOI: 10.1371/journal.pone.0170079] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 12/28/2016] [Indexed: 12/17/2022] Open
Abstract
Background Aedes aegypti is a container-inhabiting mosquito and a vector of dengue, chikungunya, and Zika viruses. In 2009 several cases of autochthonous dengue transmission were reported in Key West, Florida, USA prompting a comprehensive response to control A. aegypti. In Key West, larvae of this mosquito develop in containers around human habitations which can be numerous and labor intensive to find and treat. Aerial applications of larvicide covering large areas in a short time can be an efficient and economical method to control A. aegypti. Bacillus thuringiensis israelensis (Bti) is a bacterial larvicide which is highly target specific and appropriate for wide area spraying over urban areas, but to date, there are no studies that evaluate aerial spraying of Bti to control container mosquitoes like A. aegypti. Methodology This paper examines the effectiveness of aerial larvicide applications using VectoBac® WG, a commercially available Bti formulation, for A. aegypti control in an urban setting in the USA. Droplet characteristics and spray drop deposition were evaluated in Key West, Florida, USA. The mortality of A. aegypti in containers placed under canopy in an urban environment was also evaluated. Efficacy of multiple larvicide applications on adult female A. aegypti population reduction was compared between an untreated control and treatment site. Conclusions Droplet characteristics showed that small droplets can penetrate through dense canopy to reach small containers. VectoBac WG droplets reached small containers under heavy canopy in sufficient amounts to cause > 55% mortality on all application days and >90% mortality on 3 of 5 application days while controls had <5% mortality. Aerial applications of VectoBac WG caused significant decrease in adult female populations throughout the summer and during the 38th week (last application) the difference in adult female numbers between untreated and treated sites was >50%. Aerial larvicide applications using VectoBac WG can cover wide areas in a short period of time and can be effective in controlling A. aegypti and reducing A. aegypti-borne transmission in urban areas similar to Key West, Florida, USA.
Collapse
Affiliation(s)
- Catherine A Pruszynski
- Florida Keys Mosquito Control District, College Road, Key West, Florida, United States of America
| | - Lawrence J Hribar
- Florida Keys Mosquito Control District, College Road, Key West, Florida, United States of America
| | - Robert Mickle
- REMSpC Spray Consulting, Welsh Drive, Ayr, ON, Canada
| | - Andrea L Leal
- Florida Keys Mosquito Control District, College Road, Key West, Florida, United States of America
| |
Collapse
|
12
|
Olmo C, Marco A, Armengol X, Ortells R. Effects of Bacillus thuringiensis var. israelensis on nonstandard microcrustacean species isolated from field zooplankton communities. ECOTOXICOLOGY (LONDON, ENGLAND) 2016; 25:1730-1738. [PMID: 27640016 DOI: 10.1007/s10646-016-1708-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 08/10/2016] [Indexed: 06/06/2023]
Abstract
The toxicity of Bacillus thuringiensis var. israelensis on zooplanktonic microcrustaceans was evaluated using individuals collected in coastal wetlands where this larvicide has been used for mosquito control over the last decades. We tested five zooplankton species that coexist with mosquito larvae: two copepods (both nauplii and adults of Tropocyclops prasinus and Acantocyclops americanus), and three cladocerans (Ceriodaphnia reticulata, Chydorus sphaericus, and Daphnia cf. pulex). Our experiments included seven replicates of six concentrations (Bti Vectobac12AS 1200 Bti ITU/mg): 0, 5, 25, 50, 250, and 500 mg L-1. We analyzed acute and sub-chronic effects after a single inoculation. Despite the high variability of responses among our tested organisms, we found a general pattern of increasing mortality with concentration and time. We conclude that negative effects at the community level are not unlikely as some species were affected at doses close to those used in field applications.
Collapse
Affiliation(s)
- Carla Olmo
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Burjassot, Valencia, E-46980, Spain.
| | - Amparo Marco
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Burjassot, Valencia, E-46980, Spain
| | - Xavier Armengol
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Burjassot, Valencia, E-46980, Spain
| | - Raquel Ortells
- Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Universitat de València, Burjassot, Valencia, E-46980, Spain
| |
Collapse
|
13
|
Venter HJ, Bøhn T. Interactions between Bt crops and aquatic ecosystems: A review. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY 2016; 35:2891-2902. [PMID: 27530353 DOI: 10.1002/etc.3583] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2016] [Revised: 05/13/2016] [Accepted: 08/11/2016] [Indexed: 06/06/2023]
Abstract
The term Bt crops collectively refers to crops that have been genetically modified to include a gene (or genes) sourced from Bacillus thuringiensis (Bt) bacteria. These genes confer the ability to produce proteins toxic to certain insect pests. The interaction between Bt crops and adjacent aquatic ecosystems has received limited attention in research and risk assessment, despite the fact that some Bt crops have been in commercial use for 20 yr. Reports of effects on aquatic organisms such as Daphnia magna, Elliptio complanata, and Chironomus dilutus suggest that some aquatic species may be negatively affected, whereas other reports suggest that the decreased use of insecticides precipitated by Bt crops may benefit aquatic communities. The present study reviews the literature regarding entry routes and exposure pathways by which aquatic organisms may be exposed to Bt crop material, as well as feeding trials and field surveys that have investigated the effects of Bt-expressing plant material on such organisms. The present review also discusses how Bt crop development has moved past single-gene events, toward multigene stacked varieties that often contain herbicide resistance genes in addition to multiple Bt genes, and how their use (in conjunction with co-technology such as glyphosate/Roundup) may impact and interact with aquatic ecosystems. Lastly, suggestions for further research in this field are provided. Environ Toxicol Chem 2016;35:2891-2902. © 2016 SETAC.
Collapse
Affiliation(s)
- Hermoine J Venter
- Unit for Environmental Sciences and Management, North-West University Potchefstroom Campus, North West Province, South Africa
| | - Thomas Bøhn
- GenØk-Center for Biosafety, Tromsø, Troms, Norway
| |
Collapse
|
14
|
Zhou G, Wiseman V, Atieli HE, Lee MC, Githeko AK, Yan G. The impact of long-lasting microbial larvicides in reducing malaria transmission and clinical malaria incidence: study protocol for a cluster randomized controlled trial. Trials 2016; 17:423. [PMID: 27558161 PMCID: PMC4997667 DOI: 10.1186/s13063-016-1545-4] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2015] [Accepted: 08/06/2016] [Indexed: 12/15/2022] Open
Abstract
BACKGROUND The massive scale-up of insecticide-treated nets (ITNs) and indoor residual spraying (IRS) has led to a substantial increase in malaria vector insecticide resistance as well as in increased outdoor transmission, both of which hamper the effectiveness and efficiency of ITN and IRS. Long-lasting microbial larvicide can be a cost-effective new supplemental intervention tool for malaria control. METHODS/DESIGN We will implement the long-lasting microbial larvicide intervention in 28 clusters in two counties in western Kenya. We will test FourStar controlled release larvicide (6 % by weight Bacillus thuringiensis israelensis and 1 % Bacillus sphaerius) by applying FourStar controlled release granule formulation, 90-day briquettes, and 180-day briquettes in different habitat types. The primary endpoint is clinical malaria incidence rate and the secondary endpoint is malaria vector abundance and transmission intensity. The intervention will be conducted as a two-step approach. First, we will conduct a four-cluster trial (two clusters per county, with one of the two clusters randomly assigned to the intervention arm) to optimize the larvicide application scheme. Second, we will conduct an open-label, cluster-randomized trial to evaluate the effectiveness and cost-effectiveness of the larvicide. Fourteen clusters in each county will be assigned to intervention (treatment) or no intervention (control) by a block randomization on the basis of clinical malaria incidence, vector density, and human population size per site. We will treat each treatment cluster with larvicide for three rounds at 4-month intervals, followed by no treatment for the following 8 months. Next, we will switch the control and treatment sites. The former control sites will receive three rounds of larvicide treatment at appropriate time intervals, and former treatment sites will receive no larvicide. We will monitor indoor and outdoor vector abundance using CO2-baited CDC light traps equipped with collection bottle rotators. Clinical malaria data will be aggregated from government-run malaria treatment centers. DISCUSSION Since current first-line vector intervention methods do not target outdoor transmission and will select for higher insecticide resistance, new methods beyond bed nets and IRS should be considered. Long-lasting microbial larviciding represents a promising new tool that can target both indoor and outdoor transmission and alleviate the problem of pyrethroid resistance. It also has the potential to diminish costs by reducing larvicide reapplications. If successful, it could revolutionize malaria vector control in Africa, just as long-lasting bed nets have done. TRIAL REGISTRATION U.S. National Institute of Health, study ID NCT02392832 . Registered on 3 February 2015.
Collapse
Affiliation(s)
- Guofa Zhou
- Program in Public Health, University of California, Irvine, USA
| | - Virginia Wiseman
- School of Public Health & Community Medicine, University of New South Wales, Sydney, Australia
- Department of Global Health and Development, London School of Hygiene & Tropical Medicine, London, UK
| | - Harrysone E. Atieli
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
- Maseno University, Kisumu, Kenya
| | - Ming-Chieh Lee
- Program in Public Health, University of California, Irvine, USA
| | - Andrew K. Githeko
- Centre for Global Health Research, Kenya Medical Research Institute, Kisumu, Kenya
| | - Guiyun Yan
- Program in Public Health, University of California, Irvine, USA
| |
Collapse
|
15
|
Lagadic L, Schäfer RB, Roucaute M, Szöcs E, Chouin S, de Maupeou J, Duchet C, Franquet E, Le Hunsec B, Bertrand C, Fayolle S, Francés B, Rozier Y, Foussadier R, Santoni JB, Lagneau C. No association between the use of Bti for mosquito control and the dynamics of non-target aquatic invertebrates in French coastal and continental wetlands. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 553:486-494. [PMID: 26930319 DOI: 10.1016/j.scitotenv.2016.02.096] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2015] [Revised: 02/13/2016] [Accepted: 02/14/2016] [Indexed: 06/05/2023]
Abstract
The environmental safety of Bacillus thuringiensis subsp. israelensis (Bti) is still controversial, mainly because most of the previous field studies on its undesired effects were spatially limited and did not address the relationship between community similarity and application time and frequency. No general statement can therefore be drawn on the usage conditions of Bti that insure protection of non-target organisms. The present study was conducted in eight sites distributed over the main geographical sectors where mosquito control is implemented in mainland France and Corsica. Changes in non-target aquatic invertebrates were followed at elapsed time after repeated applications of two Bti formulations (VectoBac® WDG or 12AS) up to four consecutive years. We examined the influence of both larvicide treatments and environmental variables on community dynamics and dissimilarity between treated and control areas. As it can be argued that chironomids are the most vulnerable group of non-target invertebrates, we scrutinised potential Bti-related effects on the dynamics of their community. The use of VectoBac® WDG and 12AS in coastal and continental wetlands had no immediate or long-term detectable effect on the taxonomic structure and taxa abundance of non-target aquatic invertebrate communities, including chironomids. This applied to the main habitats where mosquito larvae occur, regardless of their geographic location. Flooding, whose frequency and duration depend on local meteorological and hydrological conditions, was identified as the main environmental driver of invertebrate community dynamics. Our findings add support to the environmental safety of currently available Bti formulations when following recommended application rates and best mosquito control practices.
Collapse
Affiliation(s)
- Laurent Lagadic
- INRA, UMR985 Écologie et Santé des Écosystèmes, Agrocampus Ouest, 65 rue de Saint Brieuc, F-35042 Rennes, France.
| | - Ralf B Schäfer
- Quantitative Landscape Ecology, Institute for Environmental Sciences, University of Koblenz-Landau, Fortstraße 7, D-76829 Landau, Germany
| | - Marc Roucaute
- INRA, UMR985 Écologie et Santé des Écosystèmes, Agrocampus Ouest, 65 rue de Saint Brieuc, F-35042 Rennes, France
| | - Eduard Szöcs
- Quantitative Landscape Ecology, Institute for Environmental Sciences, University of Koblenz-Landau, Fortstraße 7, D-76829 Landau, Germany
| | - Sébastien Chouin
- Etablissement Interdépartemental pour la Démoustication du Littoral Atlantique, 1 rue Toufaire, F-17300 Rochefort-sur-Mer, France
| | - Jérôme de Maupeou
- Etablissement Interdépartemental pour la Démoustication du Littoral Atlantique, 1 rue Toufaire, F-17300 Rochefort-sur-Mer, France
| | - Claire Duchet
- Entente Interdépartementale pour la Démoustication du Littoral Méditerranéen, 165 avenue Paul-Rimbaud, F-34184 Montpellier, France
| | - Evelyne Franquet
- Aix Marseille Université, Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE), UMR CNRS IRD Avignon Université, Faculté de Sciences et Techniques de St-Jérôme, F-13397 Marseille, France
| | - Benoit Le Hunsec
- Etablissement Interdépartemental pour la Démoustication du Littoral Atlantique, 1 rue Toufaire, F-17300 Rochefort-sur-Mer, France
| | - Céline Bertrand
- Aix Marseille Université, Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE), UMR CNRS IRD Avignon Université, Faculté de Sciences et Techniques de St-Jérôme, F-13397 Marseille, France
| | - Stéphanie Fayolle
- Aix Marseille Université, Institut Méditerranéen de Biodiversité et d'Ecologie marine et continentale (IMBE), UMR CNRS IRD Avignon Université, Faculté de Sciences et Techniques de St-Jérôme, F-13397 Marseille, France
| | - Benoît Francés
- Entente Interdépartementale pour la Démoustication du Littoral Méditerranéen, 165 avenue Paul-Rimbaud, F-34184 Montpellier, France
| | - Yves Rozier
- Entente Interdépartementale Rhône-Alpes pour la Démoustication, 31 Chemin des Prés de la Tour, F-73310 Chindrieux, France
| | - Rémi Foussadier
- Entente Interdépartementale Rhône-Alpes pour la Démoustication, 31 Chemin des Prés de la Tour, F-73310 Chindrieux, France
| | - Jean-Baptiste Santoni
- Conseil Départemental de Corse du Sud, Service de Lutte Antivectorielle, Hôtel du Département, Palais Lantivy, BP 414, F-20183 Ajaccio, France
| | - Christophe Lagneau
- Entente Interdépartementale pour la Démoustication du Littoral Méditerranéen, 165 avenue Paul-Rimbaud, F-34184 Montpellier, France
| |
Collapse
|
16
|
Vinnersten TZP, Halvarsson P, Lundström JO. Specific detection of the floodwater mosquitoes Aedes sticticus and Aedes vexans DNA in predatory diving beetles. INSECT SCIENCE 2015; 22:549-559. [PMID: 24895318 DOI: 10.1111/1744-7917.12146] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 05/04/2014] [Indexed: 06/03/2023]
Abstract
Floodwater mosquitoes (Diptera: Culicidae) are associated with periodically flooded wet meadows, marshes, and swamps in floodplains of major rivers worldwide, and their larvae are abundant in the shallow parts of flooded areas. The nuisance caused by the blood-seeking adult female mosquitoes motivates mosquito control. Larviciding with Bacillus thuringiensis israelensis is considered the most environmentally safe method. However, some concern has been raised whether aquatic predatory insects could be indirectly affected by this reduction in a potential vital prey. Top predators in the temporary wetlands in the River Dalälven floodplains are diving beetles (Coleoptera: Dytiscidae), and Aedes sticticus and Ae. vexans are the target species for mosquito control. For detailed studies on this aquatic predator-prey system, we developed a polymerase chain reaction (PCR) assay for detection of mosquito DNA in the guts of medium-sized diving beetles. Primers were designed for amplifying short mitochondrial DNA fragments of the cytochrome C oxidase subunit I (COI) gene in Ae. sticticus and Ae. vexans, respectively. Primer specificity was confirmed and half-life detectability of Ae. sticticus DNA in diving beetle guts was derived from a feeding and digestion experiment. The Ae. sticticus DNA within diving beetle guts was detected up to 12 h postfeeding, and half-life detectability was estimated to 5.6 h. In addition, field caught diving beetles were screened for Ae. sticticus and Ae. vexans DNA and in 14% of the diving beetles one or both mosquito species were detected, showing that these mosquito species are utilized as food by the diving beetles.
Collapse
Affiliation(s)
- Thomas Z Persson Vinnersten
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, SE-75236, Uppsala
- Swedish Biological Mosquito Control Project, Nedre Dalälvens Utvecklings AB, Gysinge, Sweden
| | - Peter Halvarsson
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, SE-75236, Uppsala
| | - Jan O Lundström
- Department of Ecology and Genetics, Evolutionary Biology Centre, Uppsala University, SE-75236, Uppsala
- Swedish Biological Mosquito Control Project, Nedre Dalälvens Utvecklings AB, Gysinge, Sweden
| |
Collapse
|
17
|
Duchet C, Franquet E, Lagadic L, Lagneau C. Effects of Bacillus thuringiensis israelensis and spinosad on adult emergence of the non-biting midges Polypedilum nubifer (Skuse) and Tanytarsus curticornis Kieffer (Diptera: Chironomidae) in coastal wetlands. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2015; 115:272-278. [PMID: 25728359 DOI: 10.1016/j.ecoenv.2015.02.029] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Revised: 02/10/2015] [Accepted: 02/18/2015] [Indexed: 06/04/2023]
Abstract
To optimize their efficacy, some insecticides used for mosquito control are introduced into aquatic ecosystems where mosquito larvae develop (marshes, ponds, sanitation devices) and cannot escape from the treated water. However, this raises the question of possible effects of mosquito larvicides on non-target aquatic species. Bacillus thuringiensis var. israelensis (Bti), which is well-known for its selectivity for Nematocera dipterans, is widely used for mosquito control all over the world. Spinosad, a mixture of spinosyns A and D known as fermentation products of a soil actinomycete (Saccharopolyspora spinosa), is a biological neurotoxic insecticide with a broader action spectrum. It is a candidate larvicide for mosquito control, but some studies showed that it may be toxic to beneficial or non-target species, including non-biting midges. The present study was therefore undertaken to assess the impact of Bti and spinosad on natural populations of Polypedilum nubifer (Skuse) and Tanytarsus curticornis Kieffer (Diptera: Chironomidae) in field enclosures implemented in Mediterranean coastal wetlands. Unlike Bti, spinosad had a strong lethal effect on P. nubifer and seems to affect T. curticornis at presumed recommended rates for field application. Differences in the sensitivity of these two species to spinosad confirm that population dynamics need to be known for a proper assessment of the risk encountered by chironomids in wetlands where larvicide-based mosquito control occurs.
Collapse
Affiliation(s)
- Claire Duchet
- Entente Interdépartementale de Démoustication du Littoral Méditerranéen, 165 avenue Paul-Rimbaud, F-34184 Montpellier, France.
| | - Evelyne Franquet
- Aix Marseille Université, Institut Méditerranéen de Biodiversité et Ecologie Marine et Continentale, UMR CNRS 7263/ IRD-Service 431, Pôle de l'Etoile, 13397 Marseille cedex 20, France
| | - Laurent Lagadic
- INRA, UMR985 Écologie et Santé des Écosystèmes, Équipe Écotoxicologie et Qualité des Milieux Aquatiques, Agrocampus Ouest, 65 rue de Saint Brieuc, F-35042 Rennes, France
| | - Christophe Lagneau
- Entente Interdépartementale de Démoustication du Littoral Méditerranéen, 165 avenue Paul-Rimbaud, F-34184 Montpellier, France
| |
Collapse
|
18
|
Farajollahi A, Williams GM, Condon GC, Kesavaraju B, Unlu I, Gaugler R. Assessment of a direct application of two Bacillus thuringiensis israelensis formulations for immediate and residual control of Aedes albopictus. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2013; 29:385-388. [PMID: 24551974 DOI: 10.2987/13-6332.1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The bacterial agent Bacillus thuringiensis israelensis (Bti) is a highly effective larvicide against various medically important mosquito and black fly vector species. Recent formulations of this powerful larvicidal tool have been evaluated for their field efficacy in integrated mosquito management programs. Laboratory and controlled-condition trials have indicated long periods of residual efficacy, whereas field persistence is often much lower in duration. We investigated the residual persistence of high doses of 2 formulations of Bti, a water-dispersible granule (VectoBac WDG; 16 mg/liter) and an extruded pellet (VBC-60066; 80 mg/liter), for the management of natural larval populations of Aedes albopictus. Laboratory tests demonstrated 100% (WDG) and > or = 99.7% (VBC) average mortality across all treatments over 180 days. Field tests exhibited 100% efficacy (WDG and VBC) for 3 wk against Ae. albopictus and other coinhabiting mosquito species, with some residual efficacy lasting for > 4 wk. These results are discussed in relation to current field control of domestic Aedes vectors of public health significance.
Collapse
Affiliation(s)
- Ary Farajollahi
- Center for Vector Biology, Rutgers University, 180 Jones Avenue, New Brunswick, NJ 08901-8536, USA
| | - Gregory M Williams
- Center for Vector Biology, Rutgers University, 180 Jones Avenue, New Brunswick, NJ 08901-8536, USA
| | - George C Condon
- Center for Vector Biology, Rutgers University, 180 Jones Avenue, New Brunswick, NJ 08901-8536, USA
| | - Banugopan Kesavaraju
- Salt Lake City Mosquito Abatement District, 2020 N Redwood Road, Salt Lake City, UT 84116, USA
| | - Isik Unlu
- Center for Vector Biology, Rutgers University, 180 Jones Avenue, New Brunswick, NJ 08901-8536, USA
| | - Randy Gaugler
- Center for Vector Biology, Rutgers University, 180 Jones Avenue, New Brunswick, NJ 08901-8536, USA
| |
Collapse
|
19
|
Lagadic L, Roucaute M, Caquet T. Btisprays do not adversely affect non-target aquatic invertebrates in French Atlantic coastal wetlands. J Appl Ecol 2013. [DOI: 10.1111/1365-2664.12165] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Laurent Lagadic
- INRA; UMR985 Écologie et Santé des Écosystèmes; Équipe Écotoxicologie et Qualité des Milieux Aquatiques, Agrocampus Ouest, 65 rue de Saint Brieuc F-35042 Rennes France
| | - Marc Roucaute
- INRA; UMR985 Écologie et Santé des Écosystèmes; Équipe Écotoxicologie et Qualité des Milieux Aquatiques, Agrocampus Ouest, 65 rue de Saint Brieuc F-35042 Rennes France
| | - Thierry Caquet
- INRA; UMR985 Écologie et Santé des Écosystèmes; Équipe Écotoxicologie et Qualité des Milieux Aquatiques, Agrocampus Ouest, 65 rue de Saint Brieuc F-35042 Rennes France
| |
Collapse
|
20
|
Evaluation of a commercial Bacillus thuringiensis var. israelensis formulation for the control of chironomid midge larvae (Diptera: Chironomidae) in establishing rice crops in south-eastern Australia. J Invertebr Pathol 2013; 112:9-15. [DOI: 10.1016/j.jip.2012.10.006] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2012] [Revised: 10/15/2012] [Accepted: 10/18/2012] [Indexed: 11/23/2022]
|