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Bonds JAS, Collins CM, Gouagna L. Could species-focused suppression of Aedes aegypti, the yellow fever mosquito, and Aedes albopictus, the tiger mosquito, affect interacting predators? An evidence synthesis from the literature. PEST MANAGEMENT SCIENCE 2022; 78:2729-2745. [PMID: 35294802 PMCID: PMC9323472 DOI: 10.1002/ps.6870] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/24/2022] [Revised: 03/11/2022] [Accepted: 03/16/2022] [Indexed: 06/14/2023]
Abstract
The risks of Aedes aegypti and Aedes albopictus nuisance and vector-borne diseases are rising and the adverse effects of broad-spectrum insecticide application have promoted species-specific techniques, such as sterile insect technique (SIT) and other genetic strategies, as contenders in their control operations. When specific vector suppression is proposed, potential effects on predators and wider ecosystem are some of the first stakeholder questions. These are not the only Aedes vectors of human diseases, but are those for which SIT and genetic strategies are of most interest. They vary ecologically and in habitat origin, but both have behaviorally human-adapted forms with expanding ranges. The aquatic life stages are where predation is strongest due to greater resource predictability and limited escape opportunity. These vectors' anthropic forms usually use ephemeral water bodies and man-made containers as larval habitats; predators that occur in these are mobile, opportunistic and generalist. No literature indicates that any predator depends on larvae of either species. As adults, foraging theory predicts these mosquitoes are of low profitability to predators. Energy expended hunting and consuming will mostly outweigh their energetic benefit. Moreover, as adult biomass is mobile and largely disaggregated, any predator is likely to be a generalist and opportunist. This work, which summarizes much of the literature currently available on the predators of Ae. aegypti and Ae. albopictus, indicates it is highly unlikely that any predator species depends on them. Species-specific vector control to reduce nuisance and disease is thus likely to be of negligible or limited impact on nontarget predators. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
| | | | - Louis‐Clément Gouagna
- UMR MIVEGEC (Maladies Infectieuses et Vecteurs: Écologie, Génétique, Évolution et Contrôle)IRD‐CNRS‐Univ. MontpellierMontpellierFrance
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The Odonate fauna (Insecta: Odonata) of Belihuloya, Southern Intermediate zone of Sri Lanka: a preliminary assessment and conservation implications. JOURNAL OF ASIA-PACIFIC BIODIVERSITY 2022. [DOI: 10.1016/j.japb.2022.04.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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Akhtar ZR, Tariq K, Mavian C, Ali A, Ullah F, Zang LS, Ali F, Nazir T, Ali S. Trophic transfer and toxicity of heavy metals from dengue mosquito Aedes aegypti to predator dragonfly Tramea cophysa. ECOTOXICOLOGY (LONDON, ENGLAND) 2021; 30:1108-1115. [PMID: 34165678 DOI: 10.1007/s10646-021-02448-9] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 06/09/2021] [Indexed: 06/13/2023]
Abstract
Heavy metal pollution in aquatic habitats can be detrimental to both prey and predators in a food web. To investigate the potential for bio-transfer and bioaccumulation of heavy metals between specific trophic levels, 3rd instar larvae of Aedes aegypti were exposed to mercury (Hg), lead (Pb), cadmium (Cd), copper (Cu), and zinc (Zn) for three consecutive generations and fed to dragonfly (Tramea cophysa) nymphs. Exposure to Hg caused the highest mortality in A. aegypti larvae and T. cophysa nymphs. Bioaccumulation and life-history parameters of A. aegypti, including egg hatching time, larval and pupal duration, male and female life span, and fecundity, were also evaluated after metals exposure. All life-history parameters except larval duration were significantly affected by heavy metal treatments. Bioaccumulation of metals in A. aegypti larvae and adults gradually and significantly increased from 1st to 3rd generation. To the best of our knowledge, this is the first study describing the acute toxicity of heavy metals to mosquitoes. Our study shows that heavy metals cause dietary toxicity to an aquatic predator, dragonfly, via trophic transfer, which could have considerable consequences on aquatic ecosystems.
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Affiliation(s)
- Zunnu Raen Akhtar
- Department of Entomology, University of Agriculture, Faisalabad, Pakistan
| | - Kaleem Tariq
- Department of Agriculture Entomology, Abdul Wali Khan University Mardan, Mardan, Khyber Pakhtunkhwa, Pakistan.
- Entomology and Nematology Department, Steinmetz Hall, University of Florida, Gainesville, FL, 32611, USA.
- U.S. Department of Agriculture, Agricultural Research Service, Center for Medical, Agricultural and Veterinary Entomology, Gainesville, FL, 32608, USA.
| | - Carla Mavian
- Emerging Pathogens Institute, University of Florida, Gainesville, FL, 32611, USA
| | - Asad Ali
- Department of Agriculture Entomology, Abdul Wali Khan University Mardan, Mardan, Khyber Pakhtunkhwa, Pakistan
| | - Farman Ullah
- Department of Entomology, College of Plant Protection, China Agricultural University, Beijing, 100193, China
| | - Lian-Sheng Zang
- Ayub Agricultural Research Institute, Faisalabad, Punjab, Pakistan
| | - Farman Ali
- Department of Agriculture Entomology, Abdul Wali Khan University Mardan, Mardan, Khyber Pakhtunkhwa, Pakistan
| | - Tamsila Nazir
- Key Laboratory of Green Pesticide and Agricultural Bioengineering, Guizhou University, Guiyang, P. R. China
| | - Sajjad Ali
- Department of Entomology, UCA & ES, The Islamia University of Bahawalpur, Bahawalpur, 63100, Pakistan
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Voltage-Gated Sodium Channel ( Vgsc) Mutation-Based Pyrethroid Resistance in Aedes aegypti Populations of Three Endemic Dengue Risk Areas of Sri Lanka. BIOMED RESEARCH INTERNATIONAL 2021; 2021:8874092. [PMID: 34124263 PMCID: PMC8166465 DOI: 10.1155/2021/8874092] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/30/2020] [Revised: 03/24/2021] [Accepted: 05/16/2021] [Indexed: 11/17/2022]
Abstract
Background Pyrethroid insecticides are widely used in many countries for chemical-based control of Ae. aegypti. Regardless of their efficacy, the constant use of insecticides has induced insecticide resistance mechanisms, such as knockdown resistance (kdr) in mosquitoes. Sri Lankan Vector Controlling Entities (VCE) have been using a variety of pyrethroid insecticides as the primary approach for dengue control. However, development of any resistance among the Aedes mosquitoes has been limitedly studied in the country. Therefore, the current study was conducted to evaluate the prevalence of F1534C, V1016G, and S989P mutations among Ae. aegypti mosquito populations in three dengue endemic high-risk regions of Sri Lanka. Methodology. Immature (both pupae and larvae) stages of Ae. aegypti mosquitoes were collected from Colombo, Gampaha, and Kandy districts of Sri Lanka from February 2018 to December 2019. Polymerase Chain Reaction- (PCR-) based assay for molecular genotyping of mutations was performed to identify the prevalence of kdr mutations in collected Ae. aegypti populations, separately. The frequencies of the resistant and susceptible kdr alleles were determined by using the Hardy–Weinberg equilibrium. Results The Ae. aegypti populations from Colombo, Gampaha, and Kandy districts showed 46%, 42%, and 22% of F1534C mutation allele frequencies, along with 15%, 12%, and 6% of V1016G mutation allele frequencies, respectively. The mutation allele frequencies of S989 in Colombo, Gampaha, and Kandy districts were 9.5%, 8.5%, and 4.5%, respectively. The wild-type (PP) genotype remained predominant within all the three districts, whereas the homogenous (QQ) mutation genotype occurred only in minority. The abundance of Q allele frequency in Ae. aegypti mosquitoes was relatively higher for all the three mutations in Colombo. Conclusions The findings clearly indicate that long-term insecticide applications and multiple use of pyrethroids have led to the acquisition of kdr mutations, leading to the development of insecticide resistance among local Ae. aegypti populations, especially in the Colombo and Gampaha districts. Therefore, evaluation of the prevalence levels of these kdr mutations highlights the necessity for shifting towards novel vector control strategies.
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Chagas TQ, Araújo APDC, Malafaia G. Biomicroplastics versus conventional microplastics: An insight on the toxicity of these polymers in dragonfly larvae. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 761:143231. [PMID: 33138995 DOI: 10.1016/j.scitotenv.2020.143231] [Citation(s) in RCA: 33] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2020] [Revised: 10/14/2020] [Accepted: 10/16/2020] [Indexed: 06/11/2023]
Abstract
The toxicological safety of products developed as alternative for conventional plastics (i.e., petroleum derivatives) inevitably demands conducting (eco)toxicological studies. Thus, the aim of the current study was to evaluate the biochemical toxicity of polyethylene microplastics (PE MPs) (representative of conventional MPs) and polylactic acid biomicroplastics (PLA BioMPs) in Aphylla williamsoni larvae used as experimental models. Animals subjected to short exposure to both pollutants (48 h), at environmentally relevant concentration (6 mg/L). At the end of the experiment, different toxicity biomarkers were evaluated. To assess the possible impact of pollutants on the nutritional status of the animals, the total protein, total soluble carbohydrate and triglyceride levels were determined. However, we did not observe differences between the groups, which suggests that PE MPs and PLA BioMPs did not affect the animals' energy metabolism, inducing them to a nutritional deficit. However, larvae exposed to PLA BioMPs have shown increased nitrite and lipid peroxidation levels, which supports the hypothesis that these pollutants increase oxidative stress processes in the animals evaluated, which can affect the animals' physiological homeostasis from different changes. In addition, the decrease in superoxide dismutase activity and of total thiols levels, in these same animals, is suggestive of the impact of PLA BioMPs on the antioxidant defenses, causing a REDOX imbalance, never before reported. On the other hand, decreased AChE activity was only observed in larvae exposed to PLA BioMPs, which demonstrates the anticholinergic activity of the tested polymers; the consequences of which include changes in different neurophysiological functions. Thus, the current study has helped improving the scientific knowledge about impacts caused by PLA BioMPs on freshwater ecosystems, as well as corroborated assertions about the risks posed by such biopolymers on these environments.
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Affiliation(s)
- Thales Quintão Chagas
- Biological Research Laboratory, Post-graduation Program in Conservation of Cerrado Natural Resources, Goiano Federal Institute - Urutaí Campus Urutaí, GO, Brazil
| | | | - Guilherme Malafaia
- Biological Research Laboratory, Post-graduation Program in Conservation of Cerrado Natural Resources, Goiano Federal Institute - Urutaí Campus Urutaí, GO, Brazil; Post-graduation Program in Biotechnology and Biodiversity, Goiano Federal Institute and Federal University of Goiás, GO, Brazil.
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Montalvão MF, Guimarães ATB, Rodrigues ASDL, Malafaia G. Carbon nanofibers are bioaccumulated in Aphylla williamsoni (Odonata) larvae and cause REDOX imbalance and changes of acetylcholinesterase activity. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 756:143991. [PMID: 33302068 DOI: 10.1016/j.scitotenv.2020.143991] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Revised: 11/11/2020] [Accepted: 11/15/2020] [Indexed: 06/12/2023]
Abstract
Carbon-based materials have been considered very promising for the technological industry due to their unique physical and chemical properties, namely: ability to reduce production costs and to improve the efficiency of several products. However, there is little information on what is the level of exposure that leads to adverse effects and what kind of effects is expected in aquatic biota. Thus, the aim of the present study was to evaluate the toxicity of carbon nanofibers (CNFs) in dragonfly larvae (Aphylla williamsoni) based on predictive oxidative-stress biomarkers, antioxidant activity reduction and neurotoxicity. After ephemeral models' exposure to CNFs (48 h; at 500 μg/L), data have shown that these pollutants did not change larvae's nutritional status given the concentration of total soluble carbohydrates, total proteins and triglycerides in them. However, the levels of both nitric oxide and substances reactive to thiobarbituric acid (lipid peroxidation indicators) have increased and the antioxidant activity based on total thiol levels and on 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (%) has reduced, and it suggests REDOX imbalance induction by CNFs. In addition, larvae exposed to these pollutants showed significant acetylcholinesterase activity reduction in comparison to the control group. Thus, the present study has brought further knowledge about how carbon-based materials can affect benthic macroinvertebrates and emphasized their ecotoxicological potential in freshwater environments.
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Affiliation(s)
- Mateus Flores Montalvão
- Programa de Pós-Graduação em Ecologia e Conservação de Recursos Naturais, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil
| | - Abraão Tiago Batista Guimarães
- Programa de Pós-Graduação em Ecologia e Conservação de Recursos Naturais, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil; Laboratório de Pesquisas Biológicas, Programa de Pós-Graduação em Conservação de Recursos Naturais do Cerrado, Instituto Federal Goiano, Urutaí, GO, Brazil
| | - Aline Sueli de Lima Rodrigues
- Laboratório de Pesquisas Biológicas, Programa de Pós-Graduação em Conservação de Recursos Naturais do Cerrado, Instituto Federal Goiano, Urutaí, GO, Brazil
| | - Guilherme Malafaia
- Programa de Pós-Graduação em Ecologia e Conservação de Recursos Naturais, Universidade Federal de Uberlândia, Uberlândia, MG, Brazil; Laboratório de Pesquisas Biológicas, Programa de Pós-Graduação em Conservação de Recursos Naturais do Cerrado, Instituto Federal Goiano, Urutaí, GO, Brazil; Programa de Pós-Graduação em Biotecnologia e Biodiversidade, Universidade Federal de Goiás, Goiânia, GO, Brazil.
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Guimarães ATB, de Lima Rodrigues AS, Pereira PS, Silva FG, Malafaia G. Toxicity of polystyrene nanoplastics in dragonfly larvae: An insight on how these pollutants can affect bentonic macroinvertebrates. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 752:141936. [PMID: 32889289 DOI: 10.1016/j.scitotenv.2020.141936] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2020] [Revised: 08/20/2020] [Accepted: 08/22/2020] [Indexed: 06/11/2023]
Abstract
Although nanoplastics (NPs) are known to be toxic to several groups of animals, the effects of such a toxicity on freshwater benthic macroinvertebrate communities remain unknown. Thus, the aim of the current study is to test the hypothesis that polystyrene nanoplastics (PS NPs) (34 μg/L - 48 h of exposure) lead to biochemical damage in Aphylla williamsoni larvae. Data have evidenced high bioaccumulation factor in the analyzed individuals; this finding indicates that, similar to sediments, water is also part of aquatic systems and favors PS NPs retention in dragonfly larvae. Despite the lack of evidence about the interference of these pollutants in the nutritional status of the analyzed animals, their bioaccumulation was associated with REDOX imbalance featured by concomitant increase in the number of evaluated oxidative stress biomarkers (nitric oxide and lipid peroxidation) and antioxidants (antioxidant activity against the DPPH radical and the superoxide dismutase enzyme). On the other hand, the reduced acetylcholinesterase activity observed in larvae exposed to PS NPs has suggested the neurotoxic effect of these pollutants, with potential impact on their nerve and neuromuscular functions. Therefore, the current study is pioneer in showing that PS NPs can affect the health of the investigated larvae, even at small concentrations, for short exposure-time; this outcome reinforces the ecotoxicological risk of these pollutants for freshwater benthic macroinvertebrates.
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Affiliation(s)
- Abraão Tiago Batista Guimarães
- Biological Research Laboratory, Post-graduation Program in Conservation of Cerrado Natural Resources, Goiano Federal Institute, Urutaí Campus, Urutaí, GO, Brazil; Post-graduation Program in Biotechnology and Biodiversity, Goiano Federal Institution and Federal University of Goiás, GO, Brazil
| | - Aline Sueli de Lima Rodrigues
- Biological Research Laboratory, Post-graduation Program in Conservation of Cerrado Natural Resources, Goiano Federal Institute, Urutaí Campus, Urutaí, GO, Brazil
| | - Paulo Sérgio Pereira
- Post-graduation Program in Biotechnology and Biodiversity, Goiano Federal Institution and Federal University of Goiás, GO, Brazil
| | - Fabiano Guimarães Silva
- Post-graduation Program in Biotechnology and Biodiversity, Goiano Federal Institution and Federal University of Goiás, GO, Brazil
| | - Guilherme Malafaia
- Biological Research Laboratory, Post-graduation Program in Conservation of Cerrado Natural Resources, Goiano Federal Institute, Urutaí Campus, Urutaí, GO, Brazil; Post-graduation Program in Biotechnology and Biodiversity, Goiano Federal Institution and Federal University of Goiás, GO, Brazil.
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Development of an Alternative Low-Cost Larval Diet for Mass Rearing of Aedes aegypti Mosquitoes. BIOMED RESEARCH INTERNATIONAL 2020; 2020:1053818. [PMID: 33294432 PMCID: PMC7718045 DOI: 10.1155/2020/1053818] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2020] [Revised: 11/09/2020] [Accepted: 11/11/2020] [Indexed: 12/04/2022]
Abstract
Background Aedes aegypti is a major vector of arboviruses that may be controlled on an area-wide basis, using novel approaches such as Sterile Insect Technique (SIT) and Incompatible Insect Technique (IIT). Larval diet is a critical factor to be considered in mass rearing of Aedes mosquitoes for SIT and IIT programs. Therefore, the current study is aimed at evaluating the effects of two novel diets developed from dry fish powder on the growth and development of immature stages and adult fitness-related characteristics of Ae. aegypti in Sri Lanka. Method Three batches of the first instar Ae. aegypti larva, each containing 250 larvae, were exposed to three different larval diets as standard dry fish powder (D1), dry fish powder meal and brewer's yeast (D2), and International Atomic Energy Agency- (IAEA-) recommended diet (D3), separately. Morphometric and developmental parameters of the 4th instar larvae, pupae, and adult mosquitoes reared under different dietary treatments were measured. The entire experimental setup was replicated thrice. A General Linear Model (GLM) in the form of two-way ANOVA was used for the statistical analysis. Results Significant diet-based variations were observed in the head length, head width, thoracic length, thoracic width, abdominal length, abdominal width, and total length (F2,87 > 4.811; P < 0.05) of Ae. aegypti larvae. The highest pupation success and the larval size were observed from the larvae fed the D2 diet, while the lowest was reported from D1. All adult morphometric parameters of adult male and female Ae. aegypti mosquitoes also denoted significant dietary variations, reporting the best-sized adults from the D2 diet (F2,87 > 3.54; P < 0.05). Further, significantly higher fecundity and male longevity were also shown by the adult Ae. aegypti (F2,6 > 7.897; P < 0.01) mosquitoes reared under diet D2. Conclusion Based on all the growth and developmental parameters, the D2 diet tends to perform similar to the IAEA-recommended diet in mass rearing of Ae. aegypti mosquitoes, while being more inexpensive. Therefore, larval diet D2 could be suggested as the ideal diet for mass rearing of Ae. aegypti for IIT and SIT-based vector control in Sri Lanka.
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Ranathunge T, Abeyewickreme W, Iqbal MCM, Hapugoda M. Use of cyclopoid copepods for control of Anopheles (Diptera: Culicidae) mosquito larvae to prevent re-emergence of malaria in Sri Lanka. J Vector Borne Dis 2020; 56:200-206. [PMID: 32655068 DOI: 10.4103/0972-9062.289393] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022] Open
Abstract
BACKGROUND & OBJECTIVES Although malaria is eliminated from Sri Lanka, there is a possible risk of spread from infected persons coming from malaria endemic countries. The presence of major and potential vectors in several parts of the country along with drug resistance, necessitates the identification of effective and novel control methods. The present study focused on identifying effective biological control agents for anopheline larvae using carnivorous copepods under laboratory and field conditions to prevent re-introduction of malaria in the country. METHODS Three copepod species, namely Mesocyclops scrassus, Cyclops varicans and C. languides collected from different areas in the country were cultured by adding supplementary food, and their predatory efficacy was evaluated under laboratory and field conditions. RESULTS Significant variation (p <0.05) was observed in predation rates of studied copepod species. The species M. scrassus showed the highest predacious efficiency, and consumed the highest number of anopheline larvae under laboratory and field conditions. Further, M. scrassus had higher survival rate than C. varicans and C. languides. INTERPRETATION & CONCLUSION The results of the study suggest that the predatory copepod M. scrassus can be used as a bio-control agent for the control of Anopheles mosquitoes to prevent re-emergence of malaria in the country. Additional research is suggested to identify naturally available copepod species and their predatory efficacy.
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Affiliation(s)
- Tharaka Ranathunge
- Molecular Medicine Unit, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka
| | - W Abeyewickreme
- Department of Parasitology, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka
| | - M C M Iqbal
- Plant and Environmental Sciences, National Institute of Fundamental Studies, Kandy, Sri Lanka
| | - Menaka Hapugoda
- Molecular Medicine Unit, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka
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Ong'wen F, Onyango PO, Bukhari T. Direct and indirect effects of predation and parasitism on the Anopheles gambiae mosquito. Parasit Vectors 2020; 13:43. [PMID: 32000840 PMCID: PMC6990496 DOI: 10.1186/s13071-020-3915-8] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2019] [Accepted: 01/24/2020] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND A good understanding of mosquito ecology is imperative for integrated vector control of malaria. In breeding sites, Anopheles larvae are concurrently exposed to predators and parasites. However, to our knowledge, there is no study on combined effects of predators and parasites on development and survival of larvae and their carry-over effects on adult survivorship and susceptibility to further parasite infection. METHODS This study focused on effects of the nymphs of the dragonfly Pantala flavescens and the parasitic fungus Beauveria bassiana on Anopheles gambiae, to determine: predation efficacy of nymphs against An. gambiae larvae; development rate of An. gambiae larvae in the presence of one, two or four constrained nymphs; efficacy of B. bassiana against An. gambiae larvae at doses of 3, 6 and 12 mg; and survival of adult mosquitoes exposed to B. bassiana, following pre-exposure to a constrained predator and/or parasite at the larval stage. The experiments consisted of survival bioassays quantified as pupation day, or dead larvae and/or adults. RESULTS Nymphs had an average predation efficacy of 88.3% (95% CI: 87.5-89.1) at 24 hours, against An. gambiae larvae. The presence of one or two nymphs reduced development time of larvae by 0.65 and 0.35 days, respectively. However, development time of larvae exposed to four nymphs was similar to the control larvae. Larvae exposed to 3, 6 and 12 mg of B. bassiana were 2.0, 2.5 and 3.5 times more likely to die, respectively, compared to control larvae. Adults not pre-exposed, those pre-exposed to predator, parasite, or both were 45.8, 67.4, 50.9 and 112.0 times more likely to die, respectively, compared to control that were unexposed to predator or parasite, at larval and adult stage. CONCLUSIONS This study shows that both predator and parasite can reduce larval population of An. gambiae, and presence of predator cues decreases development time in breeding sites, as well as, increases the susceptibility of emerging adult to fungus. Predator and parasite both have an additive effect on survival of adults exposed to B. bassiana. Field studies are required for an in-depth understanding of predator and parasite influence on mosquito development time, survival and susceptibility in nature.
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Affiliation(s)
- Fedinand Ong'wen
- Department of Zoology, School of Physical and Biological Sciences, Maseno University, Maseno, Kenya
| | - Patrick Ogola Onyango
- Department of Zoology, School of Physical and Biological Sciences, Maseno University, Maseno, Kenya
| | - Tullu Bukhari
- Department of Zoology, School of Physical and Biological Sciences, Maseno University, Maseno, Kenya.
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Corrigendum to “Larvicidal Potential of Five Selected Dragonfly Nymphs in Sri Lanka over Aedes aegypti (Linnaeus) Larvae under Laboratory Settings”. BIOMED RESEARCH INTERNATIONAL 2019; 2019:3950875. [PMID: 30868069 PMCID: PMC6379873 DOI: 10.1155/2019/3950875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/16/2019] [Accepted: 01/16/2019] [Indexed: 11/18/2022]
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