Selection and characterization of the Bacillus thuringiensis strains toxic to Spodoptera eridania (Cramer), Spodoptera cosmioides (Walker) and Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae)

Santos, Karen B dos; Neves, Pedro Manuel Oliveira Janeiro; Santos, Roseane Cavalcanti dos; Meneguim, Ana M.; Santos, Walter Jorge dos; Boas, G. Villas; Dumas, V. F.; Martins, E. S.; Praça, L. B.; Berry, Colin; Queiroz, P. R.; Monnerat, R. G.

doi:10.1016/j.biocontrol.2009.03.014

Cited by 69 publications

(48 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…kurstaki were obtained in lyophilized form from the Germplasm Bank of the Brazilian Agricultural Research Corporation (Embrapa) through its National Genetic Resource and Biotechnology Research Center (Cenargen), Brasilia/DF, Brazil. These strains were genetically modified to express individually Cry1Aa, Cry1Ab, Cry1Ac or Cry2A, and bioassays using the purified proteins from these genetically modified (GM) Bt spore-crystals have been published [26].…”

Section: Bt Spore-crystal Toxinsmentioning

confidence: 99%

Hematotoxicity of Bacillus thuringiensis as Spore-crystal Strains Cry1Aa, Cry1Ab, Cry1Ac or Cry2Aa in Swiss Albino Mice

Mezzomo¹,

Miranda-Vilela²,

Freire³

et al. 2013

J Hematol Thrombo Diseases

View full text Add to dashboard Cite

al. Este é um artigo de acesso aberto distribuído sob os termos da Licença de Atribuição Creative Commons, que permite uso irrestrito, distribuição e reprodução em qualquer meio, desde que o autor e a fonte originais são creditados . Journal of Hematology & Thromboembolic DiseasesResearch Article Open Access AbstractFormulated and sporulated cultures of Bacillus thuringiensis (Bt) have been widely used against insect pests, but after the advent of genetically modified plants expressing δ-endotoxins, the bioavailability of Cry proteins has been increased. For biosafety reasons their adverse effects should be studied, mainly for non-target organisms. Thus, we evaluated, in Swiss albino mice, the hematotoxicity and genotoxicity of four Bt spore-crystals genetically modified to express individually Cry1Aa, Cry1Ab, Cry1Ac or Cry2A, administered alone by gavage with a single dose of 27 mg/ Kg, 136 mg/Kg or 270 mg/Kg, 24 h, 72 h or 7 days before euthanasia. Binary combinations of these four spore-crystal proteins were also assayed at 270 mg/Kg with a single administration 24 h before euthanasia. Control mice received filtered water or cyclophosphamide at 27 mg/kg. For hematotoxicity evaluations, blood samples were drawn by cardiac puncture and processed in a multiple automated hematology analyzer; for genotoxicity analyses, micronucleus test was carried out in mice bone marrow cells. Spore-crystal administrations provoked selective hematotoxicity for the 3 exposure times, particularly for erythroid lineage. A significant reduction in bone marrow cell proliferation demonstrated cytotoxic but not genotoxic effects. These effects persisted for all exposure times, becoming more evident at 7 days. Similar results were observed for binary combinations at 24 h, suggesting that further studies are required to clarify the mechanism involved in the hematotoxicity found in mice, and to establish the toxicological risks to non-target organisms, especially mammals, before concluding that these microbiological control agents are safe for mammals.

show abstract

Section: Bt Spore-crystal Toxinsmentioning

confidence: 99%

Hematotoxicity of Bacillus thuringiensis as Spore-crystal Strains Cry1Aa, Cry1Ab, Cry1Ac or Cry2Aa in Swiss Albino Mice

Mezzomo¹,

Miranda-Vilela²,

Freire³

et al. 2013

J Hematol Thrombo Diseases

View full text Add to dashboard Cite

show abstract

“…Santos et al (2009) obtained a similar value when testing the same isolate against Spodoptera eridania. Nevertheless, LC 50 values may vary among species; for example, in studies against Spodoptera cosmioides, the LC 50 of the HD-1 standard strain was two-fold lower than that of the BR09 isolate (Santos et al, 2009 in a selection performed by Constanski et al, 2015, no differences were detected between the LC 50 of the HD-1 standard strain and that of the other isolates tested against S. eridania and S. cosmioides. The toxicological profile of the BR09 isolate that was effective against E. lignosellus can be explained by the expression of cry1 and cry2 genes, similar to the HD-1 strain, which has the cry1Aa, cry1Ab, cry1Ac, cry2A, and cry2B genes in its genome (Li et al, 2005).…”

Section: Discussionmentioning

confidence: 63%

“…In studies with the BR37 isolate, Santos et al (2009) identified eight genes of which seven were in the Cry1 group, showing the frequent occurrence of cry1 genes in isolates of B. thuringiensis (Bravo et al, 1998).…”

Section: Discussionmentioning

confidence: 99%

“…Furthermore, SDS-PAGE protein analysis of the spore and crystal mixture revealed two polypeptides with approximate molecular weights of 70-130 kDa. Santos et al (2009) also tested the BR09 isolate and showed a gene profile with cry1Aa, cry1Ab, cry1Ac, and cry2Aa genes.…”

Section: Discussionmentioning

confidence: 99%

“…For electron microscopy, the lyophilized material of each isolate used in the previous bioassays was directly deposited over metal supports and coated with gold for 180 s, using a 40 mA current under vacuum (10-1 mbar) in a BAL-TEC model SCD-050 Sputter Coater (Santos et al, 2009). Subsequently, the material was analysed using a scanning electron microscope Philips QUANTA 200 (FEI) in high vacuum under 20 kV tension with a working distance of 10.2 mm.…”

Section: Morphological Characterization Of B Thuringiensis Isolatesmentioning

confidence: 99%

See 2 more Smart Citations

Isolation and characterization of Bacillus thuringiensis strains active against Elasmopalpus lignosellus (Zeller, 1848) (Lepidoptera, Pyralidae)

et al. 2017

Self Cite

View full text Add to dashboard Cite

ABSTRACT. Elasmopalpus lignosellus (Zeller, 1848) (Lepidoptera, Pyralidae) is an insect pest of 60 economically important crops, including sugarcane, wheat, soybean, rice, beans, sorghum, peanuts, and cotton. The aim of this work was to select and characterize Bacillus thuringiensis isolates with insecticidal activity against E. Lignosellus that could be used as an alternative method of control. Selective bioassays were done to evaluate the toxicity of 47 isolates against first instar larvae of E. lignosellus. For the most toxic bacterial strains, the lethal concentration (LC 50 ) was estimated and morphological, biochemical and molecular methods were used to characterize the isolates. Among the 47 isolates tested, 12 caused mortality above 85% and showed LC 50 values from 0.038E+8 to 0.855E+8 spores mL -1. Isolates BR83, BR145, BR09, BR78, S1534, and S1302 had the lowest LC 50 values and did not differ from the standard HD-1 strain; the exception was BR83.The protein profiles produced bands with molecular masses of 60-130 kDa. The genes cry1, cry2, cry3, and cry11 were identified in the molecular characterization. The morphological analysis identified three different crystal inclusions: bipyramidal, spherical and cuboidal. Among the tested isolates, 12 isolates have potential for biotechnological control of E. Lignosellus by development of new biopesticides or genetically modified plants.Keywords: biological control, cry genes, entomopathogenic bacteria, lesser cornstalk borer. Seleção e caracterização de linhagens de Bacillus thuringiensis ativas contra Elasmopalpus lignosellus (Zeller, 1848) (Lepidoptera, Pyralidae)RESUMO. Elasmopalpus lignosellus (Zeller, 1848) (Lepidoptera, Pyralidae) é considerada praga para mais de 60 espécies de plantas cultivadas como o milho, cana-de-açúcar, trigo, soja, arroz, feijão, sorgo, amendoim e algodão. O objetivo deste trabalho foi selecionar e caracterizar isolados de Bacillus thuringiensis virulentos a E. lignosellus atuando como método alternativo de controle. Assim, 47 isolados foram avaliados em bioensaios seletivos contra lagartas de 1º ínstar de E. lignosellus. Para os isolados mais tóxicos, a concentração letal (CL 50 ) foi estimada e a sua caracterização foi realizada por métodos morfológicos, bioquímicos e moleculares. Dos 47 isolados testados, 12 causaram mortalidade acima 85% e apresentaram CL 50 entre 0.038E+8 a 0.855E+8 esporos mL -1 . Os menores valores de CL 50 foram obtidos pelos isolados BR83, BR145, BR09, BR78, S1534 e S1302, os quais não diferiram da linhagem padrão HD-1, com exceção do BR83. O perfil proteico revelou proteínas Cry entre 60 e 130 kDa, e a caracterização molecular mostrou a presença dos genes cry1, cry2, cry3 e cry11. A análise morfológica identificou três diferentes inclusões cristalinas: bipiramidais, esféricas e cuboides. Entre os isolados avaliados, 12 apresentam potencial biotecnológico para controle de E. lignosellus via formulação de novos bioinseticida ou produção de plantas transgênicas.Palavras-chave: controle biológico, genes cry...

show abstract

Selection and characterisation of an HD1‐like Bacillus thuringiensis isolate with a high insecticidal activity against Spodoptera littoralis (Lepidoptera: Noctuidae)

Azzouz

Kebaili-Ghribi

Farhat-Touzri

et al. 2013

Pest Management Science

View full text Add to dashboard Cite

show abstract

Selection and characterization of the Bacillus thuringiensis strains toxic to Spodoptera eridania (Cramer), Spodoptera cosmioides (Walker) and Spodoptera frugiperda (Smith) (Lepidoptera: Noctuidae)

Cited by 69 publications

References 33 publications

Hematotoxicity of Bacillus thuringiensis as Spore-crystal Strains Cry1Aa, Cry1Ab, Cry1Ac or Cry2Aa in Swiss Albino Mice

Hematotoxicity of Bacillus thuringiensis as Spore-crystal Strains Cry1Aa, Cry1Ab, Cry1Ac or Cry2Aa in Swiss Albino Mice

<b>Isolation and characterization of <i>Bacillus thuringiensis</i> strains active against <i>Elasmopalpus lignosellus</i> (Zeller, 1848) (Lepidoptera, Pyralidae)

Selection and characterisation of an HD1‐like Bacillus thuringiensis isolate with a high insecticidal activity against Spodoptera littoralis (Lepidoptera: Noctuidae)

Contact Info

Product

Resources

About