Combined use of the entomopathogenic fungus, Metarhizium brunneum, and the mosquito predator, Toxorhynchites brevipalpis, for control of mosquito larvae: Is this a risky biocontrol strategy?
J Invertebr Pathol
; 153: 38-50, 2018 03.
Article
em En
| MEDLINE
| ID: mdl-29425967
ABSTRACT
Mosquitoes transmit several diseases, which are of global significance (malaria, dengue, yellow fever, Zika). The geographic range of mosquitoes is increasing due to climate change, tourism and trade. Both conidial and blastospore formulations of the entomopathogenic fungus, Metarhizium brunneum ARSEF 4556, are being investigated as mosquito larvicides. However, concerns have been raised over possible non-target impacts to arthropod mosquito predators such as larvae of Toxorhynchites brevipalpis which feed on larvae of mosquito vector species. Laboratory-based, small container bioassays showed, that T. bevipalpis larvae are susceptible to relatively high concentrations (i.e.â¯≥107â¯sporesâ¯ml-1) of inoculum with blastospores being significantly more virulent than conidia. At lower concentrations (e.g.â¯<107â¯sporesâ¯ml-1), it appears that M. brunneum complements T. brevipalpis resulting in higher control than if either agent was used alone. At a concentration of 105â¯sporesâ¯ml-1, the LT50 of for conidia and blastospores alone was 5.64â¯days (95% CI 4.79-6.49â¯days) and 3.89â¯days (95% CI 3.53-4.25â¯days), respectively. In combination with T. brevipalpis, this was reduced to 3.15â¯days (95% CI 2.82-3.48â¯days) and 2.82â¯days (95% CI 2.55-3.08â¯days). Here, combined treatment with the fungus and predator was beneficial but weaker than additive. At 107 and 108â¯blastosporesâ¯ml-1, mosquito larval mortality was mostly due to the fungal pathogen when the predator was combined with blastospores. However, with conidia, the effects of combined treatment were additive/synergistic at these high concentrations. Optimisation of fungal concentration and formulation will reduce (1) risk to the predator and (2) application rates and costs of M. brunneum for control of mosquito larvae.
Palavras-chave
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Contexto em Saúde:
2_ODS3
/
3_ND
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4_TD
Problema de saúde:
2_enfermedades_transmissibles
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3_dengue
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3_malaria
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3_zoonosis
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4_dengue
Assunto principal:
Controle Biológico de Vetores
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Controle de Mosquitos
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Aedes
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Metarhizium
/
Culicidae
Tipo de estudo:
Etiology_studies
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Risk_factors_studies
Limite:
Animals
Idioma:
En
Revista:
J Invertebr Pathol
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Arábia Saudita