Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-26T21:53:31.106Z Has data issue: false hasContentIssue false

Bioassay of insecticidal Bacillus thuringiensis Cry IA delta-endotoxins against the spotted bollworm, Earias vittella Fabricius

Published online by Cambridge University Press:  19 September 2011

Gagana Kumar Mahapatro
Affiliation:
Division of Entomology
Gorakh Prasad Gupta
Affiliation:
Division of Entomology
P. Ananda Kumar
Affiliation:
National Research Centre (NRC) on Plant Biotechnology, Indian Agricultural Research Institute, New Delhi 110 012, India
Get access

Abstract

Insecticidal δ-endotoxins of Bacillus thuringiensis, Cry IA (a, b and c) were prepared from over-expressing cells of Escherichia coli and bioassayed against the third instars (6-day-old) of the spotted bollworm, Earias vittella Fabricius (Lepidoptera: Noctuidae), using artificial diet. The median lethal concentration (LC50) values were calculated for 6 days of exposure to δ-endotoxins. Cry IA(a) was found to be the most toxic (LC50 141.2 ng/cm2) followed by Cry IA(a) and Cry IA(b) with LC50 values of 224.5 and 300.5 ng/cm2 respectively. A highly significant reduction in larval weight took place in the surviving larvae treated with sub-lethal doses of the insecticidal crystal proteins.

Résumé

Les delta-endotoxines insecticides de Bacillus thuringiensis, Cry IA (a, b et c) ont été obtenues à partir de cellules d'Escherichia coli ayant un taux d'expression élevé et testées sur des chenilles du 3ème stade (âgées de 6 jours) du ver de la capsule Earias vittella Fabricius (Lepidoptera: Noctuidae), élevées sur milieu artificiel. Les valeurs de la dose létale moyenne (DL50) ont été calculées pour 6 jours d'exposition aux delta-endotoxines. Cry IA(c) est la plus toxique (DL50, 141,2 ng/cm2), suivie de Cry IA(a) et Cry IA(b) avec une DL50 de 224,5 et 300,5 ng/cm2 respectivement. Une réduction significative de poids a été constatée chez les chenilles survivantes traitées avec des doses sublétales des protéines cristallines insecticides.

Type
Research Articles
Copyright
Copyright © ICIPE 2001

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Bergvinson, D., Willcox, M. and Hoisington, D. (1997) Efficacy and deployment of transgenic plants for stemborer management. Insect Sci. Applic. 17, 157167.Google Scholar
Bradford, M.M. (1976) A rapid and sensitive method for the quantification of microgram quantities of protein utilizing the principle of protein dye binding. Analyt. Biochem. 72, 248.CrossRefGoogle Scholar
Finney, D. J. (1971) Probit Analysis. Cambridge University Press, London.Google Scholar
Gupta, G. P., Mahapatro, G. K., and Chandra, A. (1999) Partial larval rearing of Earias vittella (Fabricius). Insect Sci. Applic. 18, 371375.Google Scholar
Höfte, H., de Greve, H., Seurinck Jansen, J. S., Mahillon, J., Ampe, C., Vanderkerchove, J., Vanderbruggen, H., Montagu, M. V., Zabeau, M. and Vaek, M. (1986) Structural and functional analysis of a cloned delta-endotoxin of Bacillus thuringiensis Berliner 1715. Eur. J. Biochem. 161, 273280.Google Scholar
Höfte, H. and Whiteley, H. R. (1989) Insecticidal crystal proteins of Bacillus thuringiensis. Microbiol. Rev. 53, 242255.CrossRefGoogle ScholarPubMed
Huber Hans, E., Luthy, P., Ebersold, H. R. and Cordier, J. L. (1981) The subunits of the parasporal crystal of Bacillus thuringiensis: size, linkage and toxicity. Arch. Microbiol. 129, 1418.Google Scholar
Kranthi, S., Kranthi, K. R. and Lavhe, N. V. (1999) Baseline toxicity of Cry IA toxins to the spotted bollworm, Earias vittella F. Crop Prot. 18, 551555.Google Scholar
McGaughey, W. H. (1992) Problems of insect resistance to Bacillus thuringiensis, pp. 7885. In Proceedings of a Workshop on Bacillus thuringiensis, 24–26 September 1991 (Edited by Milner, R. and Chandler, C.), CSIRO, Division of Entomology, Canberra, ACT, 2601, Australia. 104 pp.Google Scholar
Padidam, M. (1992) The insecticidal crystal protein Cry IA(c) from Bacillus thuringiensis is highly toxic to Heliothis armigera. J. Invertebr. Pathol. 59, 109111.CrossRefGoogle Scholar
Plato, T. A. and Hood, E. M. (1992) Use of Bacillus thuringiensis chemical combinations against Heliothis species in cotton, pp. 7075. In Proceedings of a Workshop on Bacillus thuringiensis, 24–26 September 1991 (Edited by Milner, R. and Chandler, C.). CSIRO, Division of Entomology, Canberra, ACT 2601, Australia, 104 pp.Google Scholar