RESUMO
Natural factors regulating the population of chironomids were studied. The bacteria Bacillus cereus were isolated from chironomids sampled from Kuyalnitskii Firth after epizooty of Chironomus sp., and bacteria Bacillus thuringiensis spp. israelensis (Bti) were isolated from dead larva of Chironomus plumosus sampled in the Sea of Azov (3-m depth). Bti were characterized by high insecticide activity on midges Anopheles messeae Fall., Aedes cireneus Mg., and Culex pipiens pipiens f. pipiens L.
Assuntos
Bacillus cereus/isolamento & purificação , Bacillus thuringiensis/isolamento & purificação , Chironomidae , Animais , Chironomidae/microbiologia , Larva/microbiologia , Controle Biológico de Vetores , Sepse/microbiologiaRESUMO
A synchronous coinfection of the Colorado potato beetle Leptinotarsa decemlineata (Say) with the entomopathogenic bacteria Bacillus thuringiensis ssp. morrisoni Bonnifoi & de Barjak var. tenebrionis Krieg et al. and hyphomycete Metarhizium anisopliae (Metsch.) Sorokin or Beauveria bassiana (Bals.) Vuill leads to the rapid death of 95-100% of larvae. The bacteria arrest the nutrition of insects, while the fungal spores kill the weakened larvae. The synergistic effect of two pathogens is recorded at a relatively low hyphomycete titer (1-5 x 10(6) conidia/ml) and is evident in the mortality dynamics at all larval ages. These bacterial and fungal pathogens display no antagonism on artificial nutrient media. This microbial complex is highly efficient under natural conditions (80-90% larval mortality rate and no plant defoliation).
Assuntos
Bacillus thuringiensis/crescimento & desenvolvimento , Beauveria/crescimento & desenvolvimento , Besouros/microbiologia , Controle de Insetos , Metarhizium/crescimento & desenvolvimento , Controle Biológico de Vetores , Animais , Larva/microbiologiaRESUMO
Experimental evaluation of the biological risks of introducing the genetically modified microorganism (GMM) B. subtilis VKPM B-7092, an active ingredient of the probiotic VETOM 1.1, into an open system was performed. The following features of the GMM were studied: the survival rate of the GMM in bovine gastroenteric tract; its influence on the microbiocenosis; the species composition of microflora of the gastroenteric tract of the animal species; the possibility of transfer of the DNA fragment cloned in the B. subtilis bacterium and containing the gene of human leukocyte alpha2 interferon to the representatives of intestinal microflora of animals fed on the probiotic VETOM 1.1, as well as the GMM transfer to other microorganism species spread in the areas of potential getting of the GMM into the environment (soil). The study revealed no negative effects of the GMM on the animal organism and the environment, including remote aftereffects.
Assuntos
Bacillus subtilis/crescimento & desenvolvimento , Bacillus subtilis/genética , Bovinos/microbiologia , Meio Ambiente , Interferon-alfa/genética , Animais , Bacillus subtilis/isolamento & purificação , Trato Gastrointestinal/microbiologia , Transferência Genética Horizontal , Engenharia Genética , Humanos , RiscoRESUMO
Distribution study of Bacillus thuringiensis strains in Western Siberian soils allowed us to isolate crystal-forming bacteria assigned to a new pathovar of Bacillus thuringiensis ssp. tohokuensis with a toxic effect on mosquito larvae. A description of this bacterial pathovar is presented.
Assuntos
Bacillus thuringiensis , Proteínas de Bactérias , Toxinas Bacterianas , Culicidae/microbiologia , Endotoxinas , Proteínas Hemolisinas , Controle Biológico de Vetores , Microbiologia do Solo , Animais , Bacillus thuringiensis/isolamento & purificação , Bacillus thuringiensis/fisiologia , Bacillus thuringiensis/ultraestrutura , Toxinas de Bacillus thuringiensis , Proteínas de Bactérias/isolamento & purificação , Proteínas de Bactérias/toxicidade , Toxinas Bacterianas/isolamento & purificação , Toxinas Bacterianas/toxicidade , Culicidae/efeitos dos fármacos , Culicidae/crescimento & desenvolvimento , Eletroforese em Gel de Poliacrilamida , Endotoxinas/isolamento & purificação , Endotoxinas/toxicidade , Proteínas Hemolisinas/isolamento & purificação , Proteínas Hemolisinas/toxicidade , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/microbiologia , Dose Letal Mediana , SibériaRESUMO
A new subspecies of B. thuringiensis subsp. toguchini has been isolated from soil in Novosibirsk region. New subspecies forms elliptic crystals. Biologically and serologically it is different from other known subspecies.