Efficacy and Persistence of Bacillus sphaericus, Bacillus thuringiensis var. israelensis, and Methoprene Against Culiseta incidens (Diptera: Culicidae) in Tires

1990 ◽  
Vol 83 (4) ◽  
pp. 1280-1285 ◽  
Author(s):  
Vicki L. Kramer
2011 ◽  
Vol 27 (1) ◽  
pp. 45-55 ◽  
Author(s):  
John F. Anderson ◽  
Francis J. Ferrandino ◽  
Douglas W. Dingman ◽  
Andrew J. Main ◽  
Theodore G. Andreadis ◽  
...  

1982 ◽  
Vol 114 (1) ◽  
pp. 55-61 ◽  
Author(s):  
Stephen P. Wraight ◽  
Daniel Molloy ◽  
Patricia McCoy

AbstractBacillus thuringiensis var. israelensis (serotype H-14) and B. sphaericus strain 1593 were tested against Aedes stimulons larvae in the laboratory and in 38-cm-diam, open-ended cylinders embedded in the bottom detritus of a woodland pool. Estimates of LC50 were lower against fourth instars in the field at a mean temperature of 15.9 °C than in the laboratory at 21.1 °C. The greater efficacy in the field was attributed to high daytime water temperatures (mean 20.5 °C) following treatment and exposure of the larvae to substantially greater amounts of toxic material in a larger volume of water than in the laboratory. The regression of probit on log10 concentration was not linear over the entire range of mortality caused by B. sphaericus, increasing the difficulty of estimation of LC values. Bacillus sphaericus was significantly less active than B. thuringiensis.


2019 ◽  
Vol 98 (8) ◽  
pp. 893-896
Author(s):  
Svetlana A. Roslavtseva

Mosquito control is necessary to improve the epidemic and, consequently, the sanitary and hygienic situation in human settlements. At the same time, the safest and more environmentally friendly way of controlling is not the fight against adult mosquitoes, but the treatment of reservoirs with microbiological larvicides based on entomopathogenic, aerobic, spore-forming, saprophytic bacteria Bacillus thuringiensis (de Barjac) (Bti). A new serotype of the bacterium B. thuringiensis was found in Israel in the Negev desert. This serotype being more active against larvae of blood-sucking and non-blood-sucking mosquitoes and midges than previously known serotypes, was named israelensis. Bti endotoxin is a typical insecticide with intestinal type of action for different mosquito species. For example, Bti H14 is highly insecticidal to the larvae of Aedes aegypti and Ae. albopictus at very low concentrations. The parasporal body (endotoxin crystal), a crystalline protein consisted of four main polypeptides and two minor polypeptides, possesses of a larvicidal action. Larvicidal activity is associated with a synergistic effect in a combination of four polypeptides. The possibility of development of resistance to products based on Bti and Bacillus sphaericus in populations of mosquitoes (Culicidae) was investigated. The use of domestic microbiological formulations based on Bti («Baktitsid», «Larviol-pasta», and «Antinat») was shown an eradication the larvae of bloodsucking mosquitoes and midges to be possible and rational, since they are not generated resistant populations of mosquitoes. This is confirmed by more than 30 years of the use of such formulations.


1983 ◽  
Vol 29 (2) ◽  
pp. 271-275 ◽  
Author(s):  
Elizabeth West Davidson

Toxin was extracted from spores of the mosquito pathogen Bacillus sphaericus strain 1593 using 0.05 M NaOH. The molecular weight of this toxin was 35 000–54 000. Toxic activity of this extract was resistant to a variety of enzymes including subtilisin, but was degraded by pronase. Antiserum produced to 1593 spore toxin neutralized spore toxin and cytoplasmic toxin activity, but did not react with Bacillus thuringiensis var. israelensis crystal toxin, nor did var. israelensis toxin antiserum react with B. sphaericus toxin. Crystallike parasporal inclusions accompanying the B. sphaericus 1593 spores were removed by NaOH extraction.


2006 ◽  
Vol 72 (3) ◽  
pp. 1766-1770 ◽  
Author(s):  
Katherine Gammon ◽  
Gareth W. Jones ◽  
Steven J. Hope ◽  
Cláudia M. F. de Oliveira ◽  
Lêda Regis ◽  
...  

ABSTRACT Both Bacillus sphaericus and Bacillus thuringiensis subsp. israelensis produce mosquitocidal toxins during sporulation and are extensively used in the field for control of mosquito populations. All the known toxins of the latter organism are known to be encoded on a large plasmid, pBtoxis. In an attempt to combine the best properties of the two bacteria, an erythromycin resistance-marked pBtoxis plasmid was transferred to B. sphaericus by a mating technique. The resulting transconjugant bacteria were significantly more toxic to Aedes aegypti mosquitoes and were able to overcome resistance to B. sphaericus in a resistant colony of Culex quinquefasciatus, apparently due to the production of Cry11A but not Cry4A or Cry4B. The stability of the plasmid in the B. sphaericus host was moderate during vegetative growth, but segregational instability was observed, which led to substantial rates of plasmid loss during sporulation.


1998 ◽  
Vol 64 (10) ◽  
pp. 3910-3916 ◽  
Author(s):  
I. Thiéry ◽  
S. Hamon ◽  
A. Delécluse ◽  
S. Orduz

ABSTRACT The fragment containing the gene encoding the cytolytic Cyt1Ab1 protein from Bacillus thuringiensis subsp.medellin and its flanking sequences (I. Thiery, A. Delécluse, M. C. Tamayo, and S. Orduz, Appl. Environ. Microbiol. 63:468–473, 1997) was introduced into Bacillus sphaericus toxic strains 2362, 2297, and Iab872 by electroporation with the shuttle vector pMK3. Only small amounts of the protein were produced in recombinant strains 2362 and Iab872. The protein was detected in these strains only by Western blotting and immunodetection with antibody raised against Cyt1Ab1 protein. Large amounts of Cyt1Ab1 protein were produced in B. sphaericus recombinant strain 2297, and there was an additional crystal, other than that of the binary toxin, within the exosporium. The production of the Cyt1Ab1 protein in addition to the binary toxin did not increase the larvicidal activity of theB. sphaericus recombinant strain against susceptible mosquito populations of Culex pipiens orAedes aegypti. However, it partially restored (10 to 20 times) susceptibility of the resistant mosquito populations of C. pipiens (SPHAE) and Culex quinquefasciatus (GeoR) to the binary toxin. The Cyt1Ab1 protein produced in recombinantB. thuringiensis SPL407(pcyt1Ab1) was synthesized in two types of crystal—one round and with various dense areas, surrounded by an envelope, and the other a regular cuboid crystal, very similar to that found in the B. sphaericus recombinant strain.


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