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Dyczko D, Plewa-Tutaj K, Kiewra D. Entomopathogenic Fungi in Forest Habitats of Ixodes ricinus. INSECTS 2024; 15:341. [PMID: 38786897 PMCID: PMC11122030 DOI: 10.3390/insects15050341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 04/24/2024] [Accepted: 05/07/2024] [Indexed: 05/25/2024]
Abstract
(1) Background: In addition to the microclimate, host availability, and tick microbiota, soil environmental microorganisms can affect tick populations. This study aimed to (1) determine the presence and diversity of entomopathogenic fungi (EF) in forests, where ticks are abundant, and (2) estimate the effectiveness of the isolated EF strains against Ixodes ricinus. (2) Methods: EF were isolated using the trap insect method from soil collected from tick sites. A bioassay was used to estimate the effectiveness of EF against ticks. (3) Results: The presence of EF was found in all tested forest habitat types. A total of 53 strains belonging to the genera Metarhizium, Beauveria, and Isaria were isolated. All the six strains subjected to the bioassay showed potential efficacy against both adult and nymphal stages of I. ricinus; however, the strains differed in their effectiveness. The most effective isolate against I. ricinus was the soil environmental strain of Metarhizium anisopliae. (4) Conclusion: The study indicates that tick habitats can be the source of entomopathogenic fungi, which have a lethal effect on ticks, as demonstrated in preliminary laboratory tests with I. ricinus. However, for practical use, extensive field tests and further research on application methods and long-term effects are necessary to develop effective and sustainable tick management strategies.
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Affiliation(s)
| | - Kinga Plewa-Tutaj
- Department of Microbial Ecology and Acaroentomology, Faculty of Biological Sciences, University of Wrocław; 51-148 Wrocław, Poland; (D.D.); (D.K.)
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2
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Delivery and effectiveness of entomopathogenic fungi for mosquito and tick control: current knowledge and research challenges. Acta Trop 2022; 234:106627. [DOI: 10.1016/j.actatropica.2022.106627] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 07/12/2022] [Accepted: 07/28/2022] [Indexed: 02/07/2023]
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Integrative Alternative Tactics for Ixodid Control. INSECTS 2022; 13:insects13030302. [PMID: 35323601 PMCID: PMC8948879 DOI: 10.3390/insects13030302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Revised: 02/22/2022] [Accepted: 02/24/2022] [Indexed: 02/04/2023]
Abstract
Simple Summary Hard ticks are important for economic and health reasons, and control has mainly relied upon use of synthetic acaricides. Contemporary development of resistance and concerns relating to health and environmental safety have elicited exploration into alternative tactics for hard tick management. Some examples of alternative tactics involve biological control, desiccant dusts, growth regulators, vaccines, cultural methods, and ingested medications. Abstract Ixodids (hard ticks), ectoparasitic arthropods that vector the causal agents of many serious diseases of humans, domestic animals, and wildlife, have become increasingly difficult to control because of the development of resistance against commonly applied synthetic chemical-based acaricides. Resistance has prompted searches for alternative, nonconventional control tactics that can be used as part of integrated ixodid management strategies and for mitigating resistance to conventional acaricides. The quest for alternative control tactics has involved research on various techniques, each influenced by many factors, that have achieved different degrees of success. Alternative approaches include cultural practices, ingested and injected medications, biological control, animal- and plant-based substances, growth regulators, and inert desiccant dusts. Research on biological control of ixodids has mainly focused on predators, parasitoid wasps, infective nematodes, and pathogenic bacteria and fungi. Studies on animal-based substances have been relatively limited, but research on botanicals has been extensive, including whole plant, extract, and essential oil effects on ixodid mortality, behavior, and reproduction. The inert dusts kaolin, silica gel, perlite, and diatomaceous earth are lethal to ixodids, and they are impervious to environmental degradation, unlike chemical-based toxins, remaining effective until physically removed.
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Weeks ENI, Allan SA, Gezan SA, Kaufman PE. Auto-dissemination of commercially available fungal pathogens in a laboratory assay for management of the brown dog tick Rhipicephalus sanguineus. MEDICAL AND VETERINARY ENTOMOLOGY 2020; 34:184-191. [PMID: 31876331 DOI: 10.1111/mve.12426] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 10/29/2019] [Accepted: 12/09/2019] [Indexed: 06/10/2023]
Abstract
Rhipicephalus sanguineus is a canine tick that infests dogs throughout the world and is frequently found in homes and dog kennels. Management of this tick species is complicated by the presence of resistance to commonly utilized acaricides. Fungal formulations could provide a valuable alternative tool for management and are especially relevant indoors where detrimental environmental effects on fungal spores are of less concern. Two commercially available fungal formulations, one containing Metarhizium anisopliae and the other containing Beauveria bassiana, were compared for time to death and sporulation in nymphal ticks exposed for 60 min in treated filter paper packets. Beauveria bassiana exposure killed ticks faster than M. anisopliae exposure and B. bassiana was more likely to sporulate on tick cadavers than M. anisopliae. To determine whether infected ticks could disseminate fungus to their conspecifics, ticks were marked and treated with fungus before being placed with untreated ticks. Fungus was successfully transmitted from treated to untreated ticks. Mortality of ticks exposed to B. bassiana-exposed conspecifics occurred sooner than for those exposed to M. anisopliae-exposed conspecifics, indicating faster dissemination in the former. Therefore, although both formulations resulted in decreased longevity of ticks compared with the controls, the B. bassiana formulation holds the most promise for direct or indirect application with respect to brown dog tick management.
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Affiliation(s)
- E N I Weeks
- Entomology and Nematology Department, University of Florida, Gainesville, FL, U.S.A
| | - S A Allan
- USDA-ARS, Center for Medical, Agricultural and Veterinary Entomology, Gainesville, FL, U.S.A
| | - S A Gezan
- School of Forest Resources and Conservation, University of Florida, Gainesville, FL, U.S.A
| | - P E Kaufman
- Entomology and Nematology Department, University of Florida, Gainesville, FL, U.S.A
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5
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Fiorotti J, Menna-Barreto RFS, Gôlo PS, Coutinho-Rodrigues CJB, Bitencourt ROB, Spadacci-Morena DD, Angelo IDC, Bittencourt VREP. Ultrastructural and Cytotoxic Effects of Metarhizium robertsii Infection on Rhipicephalus microplus Hemocytes. Front Physiol 2019; 10:654. [PMID: 31191351 PMCID: PMC6548823 DOI: 10.3389/fphys.2019.00654] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2019] [Accepted: 05/09/2019] [Indexed: 12/15/2022] Open
Abstract
Metarhizium is an entomopathogenic fungus widely employed in the biological control of arthropods. Hemocytes present in the hemolymph of invertebrates are the cells involved in the immune response of arthropods. Despite this, knowledge about Rhipicephalus microplus hemocytes morphological aspects as well as their role in response to the fungal infection is scarce. The present study aimed to analyze the hemocytes of R. microplus females after Metarhizium robertsii infection, using light and electron microscopy approaches associated with the cytotoxicity evaluation. Five types of hemocytes (prohemocytes, spherulocytes, plasmatocytes, granulocytes, and oenocytoids) were described in the hemolymph of uninfected ticks, while only prohemocytes, granulocytes, and plasmatocytes were observed in fungus-infected tick females. Twenty-four hours after the fungal infection, only granulocytes and plasmatocytes were detected in the transmission electron microscopy analysis. Hemocytes from fungus-infected tick females showed several cytoplasmic vacuoles with different electron densities, and lipid droplets in close contact to low electron density vacuoles, as well as the formation of autophagosomes and subcellular material in different stages of degradation could also be observed. M. robertsii propagules were more toxic to tick hemocytes in the highest concentration tested (1.0 × 108 conidia mL-1). Interestingly, the lowest fungus concentration did not affect significantly the cell viability. Microanalysis showed that cells granules from fungus-infected and uninfected ticks had similar composition. This study addressed the first report of fungal cytotoxicity analyzing ultrastructural effects on hemocytes of R. microplus infected with entomopathogenic fungi. These results open new perspectives for the comprehension of ticks physiology and pathology, allowing the identification of new targets for the biological control.
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Affiliation(s)
- Jéssica Fiorotti
- Programa de Pós-Graduação em Ciências Veterinárias, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
| | | | - Patrícia Silva Gôlo
- Departamento de Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
| | | | - Ricardo Oliveira Barbosa Bitencourt
- Programa de Pós-Graduação em Ciências Veterinárias, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
| | | | - Isabele da Costa Angelo
- Departamento de Epidemiologia e Saúde Pública, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Brazil
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6
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Yaakov N, Ananth Mani K, Felfbaum R, Lahat M, Da Costa N, Belausov E, Ment D, Mechrez G. Single Cell Encapsulation via Pickering Emulsion for Biopesticide Applications. ACS OMEGA 2018; 3:14294-14301. [PMID: 30411063 PMCID: PMC6217693 DOI: 10.1021/acsomega.8b02225] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 10/11/2018] [Indexed: 05/15/2023]
Abstract
A new approach for single cell microencapsulation in an oil-in-water (o/w) Pickering emulsion is presented. The water/paraffin emulsions were stabilized by amine-functionalized silica nanoparticles. The droplet size of the emulsions was highly tunable, and ranged from 1 to 30 μm in diameter. The controllable droplet size along with the high colloidal stability of the Pickering emulsionswas harnessed to obtain single cell microencapsulation. Successful encapsulation of the conidia entomopathogenic fungus Metarhizium brunneum by the studied Pickering emulsions was confirmed via confocal laser scanning microscopy. The resulting systems were implemented to develop a novel biopesticide formulation for arthropod pest control. The conidia incorporated in the emulsions were applied to Ricinus communis leaves by spray assay. After drying of the emulsion, a silica-based honeycomb-like structure with an ordered hierarchical porosity is formed. This structure preserves the individual cell encapsulation. The successful single cell encapsulation has led to a high distribution of conidia cells on the leaves. The Pickering emulsion-based formulation exhibited significantly higher pest control activity against Spodoptera littoralis larvae compared to the control systems, thus making it a promising, cost-effective, innovative approach for tackling the pest control challenge.
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Affiliation(s)
- Noga Yaakov
- Department
of Food Quality & Safety, Institute for Postharvest
and Food Sciences, Department of Entomology and Nematology, Institute of Plant Protection, and Department of
Ornamental Plants and Agricultural Biotechnology, Institute of Plant
Science, Volcani Center, ARO, Rishon LeZion 7528809, Israel
| | - Karthik Ananth Mani
- Department
of Food Quality & Safety, Institute for Postharvest
and Food Sciences, Department of Entomology and Nematology, Institute of Plant Protection, and Department of
Ornamental Plants and Agricultural Biotechnology, Institute of Plant
Science, Volcani Center, ARO, Rishon LeZion 7528809, Israel
| | - Reut Felfbaum
- Department
of Food Quality & Safety, Institute for Postharvest
and Food Sciences, Department of Entomology and Nematology, Institute of Plant Protection, and Department of
Ornamental Plants and Agricultural Biotechnology, Institute of Plant
Science, Volcani Center, ARO, Rishon LeZion 7528809, Israel
- The
Mina and Everard Goodman Faculty of Life Sciences, Bar-Ilan University, Ramat Gan 5290002, Israel
| | - Magen Lahat
- Department
of Food Quality & Safety, Institute for Postharvest
and Food Sciences, Department of Entomology and Nematology, Institute of Plant Protection, and Department of
Ornamental Plants and Agricultural Biotechnology, Institute of Plant
Science, Volcani Center, ARO, Rishon LeZion 7528809, Israel
| | - Noam Da Costa
- Department
of Food Quality & Safety, Institute for Postharvest
and Food Sciences, Department of Entomology and Nematology, Institute of Plant Protection, and Department of
Ornamental Plants and Agricultural Biotechnology, Institute of Plant
Science, Volcani Center, ARO, Rishon LeZion 7528809, Israel
| | - Eduard Belausov
- Department
of Food Quality & Safety, Institute for Postharvest
and Food Sciences, Department of Entomology and Nematology, Institute of Plant Protection, and Department of
Ornamental Plants and Agricultural Biotechnology, Institute of Plant
Science, Volcani Center, ARO, Rishon LeZion 7528809, Israel
| | - Dana Ment
- Department
of Food Quality & Safety, Institute for Postharvest
and Food Sciences, Department of Entomology and Nematology, Institute of Plant Protection, and Department of
Ornamental Plants and Agricultural Biotechnology, Institute of Plant
Science, Volcani Center, ARO, Rishon LeZion 7528809, Israel
| | - Guy Mechrez
- Department
of Food Quality & Safety, Institute for Postharvest
and Food Sciences, Department of Entomology and Nematology, Institute of Plant Protection, and Department of
Ornamental Plants and Agricultural Biotechnology, Institute of Plant
Science, Volcani Center, ARO, Rishon LeZion 7528809, Israel
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Weeks EN, Machtinger ET, Leemon D, Geden CJ. 12. Biological control of livestock pests: entomopathogens. ECOLOGY AND CONTROL OF VECTOR-BORNE DISEASES 2018. [DOI: 10.3920/978-90-8686-863-6_12] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Emma N.I. Weeks
- University of Florida, Entomology and Nematology Dept., 970 Natural Area Drive, Gainesville, FL 32653, USA
| | - Erika T. Machtinger
- Penn State University, Department of Entomology, 501 ASI Building, University Park, State College, PA 16082, USA
| | - Diana Leemon
- Department of Agriculture and Fisheries (Queensland), Agri-Science Queensland, Ecosciences Precinct, GPO Box 267, Brisbane, Queensland, 4001, Australia
| | - Christopher J. Geden
- United States Department of Agriculture, Agricultural Research Service, Center for Medical, Agricultural and Veterinary Entomology, 1600 SW 23rd Drive, Gainesville, FL 32608, USA
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de Paulo JF, Camargo MG, Coutinho-Rodrigues CJB, Marciano AF, de Freitas MC, da Silva EM, Gôlo PS, Morena DDS, da Costa Angelo I, Bittencourt VREP. Rhipicephalus microplus infected by Metarhizium: unveiling hemocyte quantification, GFP-fungi virulence, and ovary infection. Parasitol Res 2018; 117:1847-1856. [PMID: 29700639 DOI: 10.1007/s00436-018-5874-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2018] [Accepted: 04/11/2018] [Indexed: 12/17/2022]
Abstract
Hemocytes, cells present in the hemocoel, are involved in the immune response of arthropods challenged with entomopathogens. The present study established the best methodology for harvesting hemocytes from Rhipicephalus microplus and evaluated the number of hemocytes in addition to histological analysis from ovaries of fungus-infected females and tested the virulence of GFP-fungi transformants. Different centrifugation protocols were tested, and the one in which presented fewer disrupted cells and higher cell recovery was applied for evaluating the effect of Metarhizium spp. on hemocytes against R. microplus. After processing, protocol number 1 (i.e., hemolymph samples were centrifuged at 500×g for 3 min at 4 °C) was considered more efficient, with two isolates used (Metarhizium robertsii ARSEF 2575 and Metarhizium anisopliae ARSEF 549), both wild types and GFP, to assess their virulence. In the biological assays, the GFP-fungi were as virulent as wild types, showing no significant differences. Subsequently, hemocyte quantifications were performed after inoculation, which exhibited notable changes in the number of hemocytes, reducing by approximately 80% in females previously treated with Metarhizium isolates in comparison to non-treated females. Complementarily, 48 h after inoculation, in which hemolymph could not be obtained, histological analysis showed the high competence of these fungi to colonize ovary from ticks. Here, for the first time, the best protocol (i.e., very low cell disruption and high cell recovery) for R. microplus hemocyte obtaining was established aiming to guide directions to other studies that involves cellular responses from ticks to fungi infection.
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Affiliation(s)
- Jéssica Fiorotti de Paulo
- Programa de Pós Graduação em Ciências Veterinárias, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Mariana Guedes Camargo
- Programa de Pós Graduação em Ciências Veterinárias, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Caio Junior Balduino Coutinho-Rodrigues
- Programa de Pós Graduação em Ciências Veterinárias, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Allan Felipe Marciano
- Programa de Pós Graduação em Ciências Veterinárias, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Maria Clemente de Freitas
- Programa de Pós Graduação em Ciências Veterinárias, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Emily Mesquita da Silva
- Programa de Pós Graduação em Ciências Veterinárias, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Patrícia Silva Gôlo
- Departamento de Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, BR 465 Km 07, Seropédica, Rio de Janeiro, 23890-000, Brazil
| | | | - Isabele da Costa Angelo
- Departamento de Epidemiologia e Saúde Pública, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Seropédica, Rio de Janeiro, Brazil
| | - Vânia Rita Elias Pinheiro Bittencourt
- Departamento de Parasitologia Animal, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, BR 465 Km 07, Seropédica, Rio de Janeiro, 23890-000, Brazil.
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Heat-stressed Metarhizium anisopliae: viability (in vitro) and virulence (in vivo) assessments against the tick Rhipicephalus sanguineus. Parasitol Res 2016; 116:111-121. [PMID: 27704216 DOI: 10.1007/s00436-016-5267-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2016] [Accepted: 09/19/2016] [Indexed: 12/26/2022]
Abstract
The current study investigated the thermotolerance of Metarhizium anisopliae s.l. conidia from the commercial products Metarril® SP Organic and Metarril® WP. The efficacy of these M. anisopliae formulations against the tick Rhipicephalus sanguineus s.l. was studied in laboratory under optimum or heat-stress conditions. The products were prepared in water [Tween® 80, 0.01 % (v/v)] or pure mineral oil. Conidia from Metarril® SP Organic suspended in water presented markedly delayed germination after heating to constant 40 °C (for 2, 4, or 6 h) compared to conidia suspended in mineral oil. Metarril® SP Organic suspended in oil and exposed to daily cycles of heat-stress (40 °C for 4 h and 25 °C for 19 h for 5 consecutive days) presented relative germination of conidia ranging from 92.8 to 87.2 % from day 1 to day 5, respectively. Conversely, germination of conidia prepared in water ranged from 79.3 to 39.1 % from day 1 to day 5, respectively. Culturability of Metarril® WP decreased from 96 % when conidia were cultured for 30 min prior to heat exposure (40 °C for 4 h) to 9 % when conidia were cultured for 8 h. Tick percent control was distinctly higher when engorged females were treated with oil suspensions rather than water suspensions, even when treated ticks were exposed to heat-stress regimen. Oil-based applications protected fungal conidia against heat-stress. Although Metarril® is not registered for tick control, it may be useful for controlling R. sanguineus, especially if it is prepared in mineral oil.
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Murigu MM, Nana P, Waruiru RM, Nga’nga’ CJ, Ekesi S, Maniania NK. Laboratory and field evaluation of entomopathogenic fungi for the control of amitraz-resistant and susceptible strains of Rhipicephalus decoloratus. Vet Parasitol 2016; 225:12-8. [DOI: 10.1016/j.vetpar.2016.05.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Revised: 05/16/2016] [Accepted: 05/21/2016] [Indexed: 02/07/2023]
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11
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Efficacy of the entomopathogenic fungus Metarhizium brunneum in controlling the tick Rhipicephalus annulatus under field conditions. Vet Parasitol 2016; 206:258-66. [PMID: 25468024 DOI: 10.1016/j.vetpar.2014.10.019] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2014] [Revised: 10/01/2014] [Accepted: 10/08/2014] [Indexed: 12/25/2022]
Abstract
High infectivity of entomopathogenic fungi to ticks under laboratory conditions has been demonstrated in many studies. However, the few reports on their use under field conditions demonstrate large variations in their success, often with no clear explanation. The present study evaluated the factors affecting the efficacy of the fungus Metarhizium brunneum against the tick Rhipicephalus (Boophilus) annulatus. It demonstrates how environmental conditions and ground cover affect the efficiency of the fungus under field conditions. During the summer, 93% of tick females exposed to fungus-contaminated ground died within 1 week, whereas during the winter, only 62.2% died within 6 weeks. Nevertheless, the hatchability of their eggs was only 6.1% during the summer and 0.0% during winter. Covering the ground with grass, leaves or gravel improved fungal performance. Aside from killing female ticks, the fungus had a substantial effect on tick fecundity. Fungal infection reduced the proportion of female ticks laying full-size egg masses by up to 91%, and reduced egg hatchability by up to 100%. To reduce the negative effect of outdoor factors on fungal activity, its conidia were mixed with different oils (olive, canola, mineral or paraffin at 10% v/v) and evaluated in both laboratory and field tests for efficacy. All tested oils without conidia sprayed on the sand did not influence tick survival or weight of the laid eggs but significantly reduced egghatchability. Conidia in water with canola or mineral oil spread on agarose and incubated for 18 h showed 57% and 0% germination, respectively. Comparing, under laboratory conditions, the effects of adding each of the four oils to conidia in water on ticks demonstrated no effect on female mortality or weight of the laid egg mass, but the percentage of hatched eggs was reduced. In outdoor trials, female ticks placed on the ground sprayed with conidia in water yielded an average of 175 larvae per female and there was no hatching of eggs laid by females placed on ground sprayed with conidia in water with canola or mineral oils.
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12
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Machado-Ferreira E, Vizzoni VF, Piesman J, Gazeta GS, Soares CAG. Bacteria associated with Amblyomma cajennense tick eggs. Genet Mol Biol 2015; 38:477-83. [PMID: 26537602 PMCID: PMC4763323 DOI: 10.1590/s1415-475738420150040] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2015] [Accepted: 05/25/2015] [Indexed: 01/27/2023] Open
Abstract
Ticks represent a large group of pathogen vectors that blood feed on a diversity of hosts. In the Americas, the Ixodidae ticks Amblyomma cajennense are responsible for severe impact on livestock and public health. In the present work, we present the isolation and molecular identification of a group of culturable bacteria associated with A. cajennense eggs from females sampled in distinct geographical sites in southeastern Brazil. Additional comparative analysis of the culturable bacteria from Anocentor nitens, Rhipicephalus sanguineus and Ixodes scapularis tick eggs were also performed. 16S rRNA gene sequence analyses identified 17 different bacterial types identified as Serratia marcescens, Stenotrophomonas maltophilia, Pseudomonas fluorescens, Enterobacter spp., Micrococcus luteus, Ochrobactrum anthropi, Bacillus cereus and Staphylococcus spp., distributed in 12 phylogroups. Staphylococcus spp., especially S. sciuri, was the most prevalent bacteria associated with A. cajennense eggs, occurring in 65% of the samples and also frequently observed infecting A. nitens eggs. S. maltophilia, S. marcescens and B. cereus occurred infecting eggs derived from specific sampling sites, but in all cases rising almost as pure cultures from infected A. cajennense eggs. The potential role of these bacterial associations is discussed and they possibly represent new targets for biological control strategies of ticks and tick borne diseases.
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Affiliation(s)
- Erik Machado-Ferreira
- Laboratório de Genética Molecular de Eucariontes e Simbiontes, Deptartamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Vinicius Figueiredo Vizzoni
- Laboratório de Genética Molecular de Eucariontes e Simbiontes, Deptartamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
| | - Joseph Piesman
- Bacterial Diseases Branch, Division of Vector-Borne Diseases, Centers for Disease Control and Prevention, Fort Collins, CO, USA
| | - Gilberto Salles Gazeta
- Laboratorio de Referência Nacional em Vetores das Riquetsioses, Instituto Oswaldo Cruz, Rio de Janeiro, RJ, Brazil
| | - Carlos Augusto Gomes Soares
- Laboratório de Genética Molecular de Eucariontes e Simbiontes, Deptartamento de Genética, Instituto de Biologia, Universidade Federal do Rio de Janeiro, Rio de Janeiro, RJ, Brazil
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