Investigation of biota associated and natural infection by sporulated bacteria in Culicidae larvae from São Paulo state, Brazil.

The aim of this study was to investigate the naturally occurring bacteria from Culicidae larvae found in São Paulo state between 2006 and 2008 from the Tiete Ecological Park in the municipality of Caraguatatuba. Bacterial strains were obtained after surface sterilization of larvae followed by thermal treatment and incubation in bacteriological media under laboratory conditions. Identification was determined using cytomorphology, biochemical and physiological tests. Strains were characterized by qualitative evaluation of biological activity against Culicidae larvae, comparing protein profiles obtained by electrophoresis of crystal protoxins, electrophoresis of Lysinibacillus sphaericus isoenzymes, detection of the L(2) fraction of Hemolytic BL enterotoxin and amplification of DNA using Multiplex-PCR to detect HBL, NHE, CytK, BceT and EntFM enterotoxins. The results obtained in this study demonstrated that the endosymbiotic bacterial diversity belonging to Bacillus and related genera associated with Culicidae larvae is limited to a number of species that does not vary throughout the seasons.

Biological activity of Bacillus thuringiensis strains against larvae of the Blowfly Chrysomya putoria (Wiedemann) (Diptera: Calliphoridae)

Different strains of Bacillus thuringiensis Berliner were proved to be a powerful biologic insecticide against larvae of several insect orders. Due to the epidemiological importance of blowflies of the Chrysomya Robineau-Desvoidy genus in the production of secondary cutaneous myiasis and mechanic transmission of pathogenic agents, the performance of two strains of B. thuringiensis (LFB-FIOCRUZ 907 and LFB-FIOCRUZ 856) was tested against larvae of Chrysomya putoria (Wiedemann). The LFB-FIOCRUZ 907 strain was tested in four different concentrations, added to the diet; the LFB-FIOCRUZ 856 strain was tested in three concentrations. C. putoria larvae showed sensibility to the treatment with the LFB-FIOCRUZ 907 strain at the tested concentrations. The higher concentration presented the best efficiency, causing higher mortality and reducing larval weight and adult emergence more intensely. The LFB-FIOCRUZ 856 strain showed low toxicity, sliglity reducing emergence time of adults at 326 mg/ 25 g concentration and larval weight at 326 mg/ 25 g and 86 mg/ 25 g concentrations.

Diferentes linhagens de Bacillus thuringiensis Berliner têm provado ser poderoso inseticida biológico contra larvas de várias ordens de insetos. Dada a importância epidemiológica das moscas do gênero Chrysomya Robineau-Desvoidy na produção de miíases cutâneas secundárias e transmissão mecânica de agentes patogênicos, avaliou-se a atividade de duas linhagens de B. thuringiensis (LFB-FIOCRUZ 907 e LFB-FIOCRUZ 856) sobre larvas de Chrysomya putoria (Wiedemann). A linhagem LFB-FIOCRUZ 907 foi testada em quatro diferentes concentrações misturadas à dieta e a linhagem LFB-FIOCRUZ 856 em três concentrações. As larvas de C. putoria apresentaram sensibilidade ao tratamento com a linhagem LFB-FIOCRUZ 907, nas concentrações testadas, sendo a concentração mais alta a de maior eficiência, causando maior mortalidade e reduzindo mais intensamente o peso larval e a taxa de emergência dos adultos. A linhagem LFB-FIOCRUZ 856 apresentou toxicidade muito baixa, redizindo ligeiramente a emergência dos adultos na concentração de 326 mg/ 25 g e o peso larval nas concentrações de 326 mg/ 25 g e 86 mg/ 25 g.

Biological activity of Bacillus thuringiensis strains against larvae of the blowfly Chrysomya putoria (Wiedemann) (Diptera: Calliphoridae).

Different strains of Bacillus thuringiensis Berliner were proved to be a powerful biologic insecticide against larvae of several insect orders. Due to the epidemiological importance of blowflies of the Chrysomya Robineau-Desvoidy genus in the production of secondary cutaneous myiasis and mechanic transmission of pathogenic agents, the performance of two strains of B. thuringiensis (LFB-FIOCRUZ 907 and LFB-FIOCRUZ 856) was tested against larvae of Chrysomya putoria (Wiedemann). The LFB-FIOCRUZ 907 strain was tested in four different concentrations, added to the diet; the LFB-FIOCRUZ 856 strain was tested in three concentrations. C. putoria larvae showed sensibility to the treatment with the LFB-FIOCRUZ 907 strain at the tested concentrations. The higher concentration presented the best efficiency, causing higher mortality and reducing larval weight and adult emergence more intensely. The LFB-FIOCRUZ 856 strain showed low toxicity, slightly reducing emergence time of adults at 326 mg/25 g concentration and larval weight at 326 mg/25 g and 86 mg/25 g concentrations.

A new black fly isolate of Bacillus thuringiensis autoagglutinating strain highly toxic to Simulium pertinax (Kollar) (Diptera, Simuliidae) larvae

Formulations containing the entomopathogenic Bacillus thuringiensis serovar israelensis strain IPS-82 has been widely applied for mosquito control around the world. Strain IPS-82 is highly active against Aedes aegypti but less active against other well-known vectors such as Culex quinquefasciatus and Simulium spp. larvae. Eighteen strains of B. thuringiensis were isolated from Simulium pertinax larvae naturally occurring in rivers of Southeast Brazil with one demonstrating special toxic effects. Simulated field tests against S. pertinax larvae showed that the native Brazilian autoagglutinanting B. thuringiensis (LFB-FIOCRUZ 1035) has an LC50 at least 25 times lower than the standard IPS-82 strain. The same bacterial preparation was also tested against Ae. aegypti larvae in laboratory trials and the LC50 values obtained with LFB-FIOCRUZ 1035 were at least three times lower than the one for the IPS 82 strain. The results indicate that this strain is more toxic than the standard B. thuringiensis serovar israelensis (H14) in the two Dipteran species tested. It is noteworthy that differences between LC50 values were more pronounced in S. pertinax larvae, the source of the original isolation.

A bioassay method for black flies (Diptera: Simuliidae) using larvicides

Esta nota apresenta um método alternativo para bioensaios com larvas de simulídeos, com que se espera proporcionar aos pesquisadores uma ferramenta mais simples, porém igualmente efetiva para a obtenção de dados referentes à eficácia de larvicidas.

A new black fly isolate of Bacillus thuringiensis autoagglutinating strain highly toxic to Simulium pertinax (Kollar) (Diptera, Simuliidae) larvae.

Formulations containing the entomopathogenic Bacillus thuringiensis serovar israelensis strain IPS-82 has been widely applied for mosquito control around the world. Strain IPS-82 is highly active against Aedes aegypti but less active against other well-known vectors such as Culex quinquefasciatus and Simulium spp. larvae. Eighteen strains of B. thuringiensis were isolated from Simulium pertinax larvae naturally occurring in rivers of Southeast Brazil with one demonstrating special toxic effects. Simulated field tests against S. pertinax larvae showed that the native Brazilian autoagglutinating B. thuringiensis (LFB-FIOCRUZ 1035) has an LC50 at least 25 times lower than the standard IPS-82 strain. The same bacterial preparation was also tested against Ae. aegypti larvae in laboratory trials and the LC50 values obtained with LFB-FIOCRUZ 1035 were at least three times lower than the one for the IPS 82 strain. The results indicate that this strain is more toxic than the standard B. thuringiensis serovar israelensis (H14) in the two Dipteran species tested. It is noteworthy that differences between LC50 values were more pronounced in S. pertinax larvae, the source of the original isolation.

Catálogo de linhagens: coleção de culturas do gênero Bacillus e gêneros correlatos / Catalogue of strains: collection of cultures of the genus Bacillus and related genera

A atual Coleção de Culturas do Gênero Bacillus e Gêneros Correlatos, acrônimo CCGB, surgiu em 1979 quando iniciou suas atividades colecionando espécies de Bacillus com propriedades amilolíticas, proteolíticas e antibióticas, isoladas do ambiente de acordo com programa específico do LFB.

Catálogo de linhagens: coleção de culturas do gênero Bacillus e gêneros correlatos

A atual Coleção de Culturas do Gênero Bacillus e Gêneros Correlatos, acrônimo CCGB, surgiu em 1979 quando iniciou suas atividades colecionando espécies de Bacillus com propriedades amilolíticas, proteolíticas e antibióticas, isoladas do ambiente de acordo com programa específico do LFB