This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Reprints and Permissions Copyright Information Books from ASM Press MicrobeWorld Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Herrero, S. Articles by Ferré, J. Search for Related Content PubMed PubMed Citation Articles by Herrero, S. Articles by Ferré, J. Agricola Articles by Herrero, S. Articles by Ferré, J.

 Previous Article  |  Next Article 

Applied and Environmental Microbiology, August 2002, p. 4090-4094, Vol. 68, No. 8
0099-2240/02/$04.00+0     DOI: 10.1128/AEM.68.8.4090-4094.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.

Extent of Variation of the Bacillus thuringiensis Toxin Reservoir: the Case of the Geranium Bronze, Cacyreus marshalli Butler (Lepidoptera: Lycaenidae)

Salvador Herrero,¹ Marisé Borja,² and Juan Ferré^1*

Department of Genetics, University of Valencia, 46100 Burjassot (Valencia),¹ Department of Research and Development, Fundación PROMIVA, 28660 Boadilla del Monte (Madrid), Spain²

Received 21 February 2002/ Accepted 17 May 2002

Despite the fact that around 200 cry genes from Bacillus thuringiensis have already been cloned, only a few Cry proteins are toxic towards a given pest. A crucial step in the mode of action of Cry proteins is binding to specific sites in the midgut of susceptible insects. Binding studies in insects that have developed cross-resistance discourage the combined use of Cry proteins sharing the same binding site. If resistance management strategies are to be implemented, the arsenal of Cry proteins suitable to control a given pest may be not so vast as it might seem at first. The present study evaluates the potential of B. thuringiensis for the control of a new pest, the geranium bronze (Cacyreus marshalli Butler), a butterfly that is threatening the popularity of geraniums in Spain. Eleven of the most common Cry proteins from the three lepidopteran-active Cry families (Cry1, Cry2, and Cry9) were tested against the geranium bronze for their toxicity and binding site relationships. Using ¹²⁵I-labeled Cry1A proteins we found that, of the seven most active Cry proteins, six competed for binding to the same site. For the long-term control of the geranium bronze with B. thuringiensis-based insecticides it would be advisable to combine any of the Cry proteins sharing the binding site (preferably Cry1Ab, since it is the most toxic) with those not competing for the same site. Cry1Ba would be the best choice of these proteins, since it is significantly more toxic than the others not binding to the common site.

---

* Corresponding author. Mailing address: Department of Genetics, University of Valencia, Dr. Moliner 50, 46100 Burjassot (Valencia), Spain. Phone: (34) 96 386 4506. Fax: (34) 96 398 3029. E-mail: Juan.Ferre{at}uv.es.

---

Applied and Environmental Microbiology, August 2002, p. 4090-4094, Vol. 68, No. 8
0099-2240/02/$04.00+0     DOI: 10.1128/AEM.68.8.4090-4094.2002
Copyright © 2002, American Society for Microbiology. All Rights Reserved.

This article has been cited by other articles:

• Ruiz de Escudero, I., Estela, A., Escriche, B., Caballero, P. (2007). Potential of the Bacillus thuringiensis Toxin Reservoir for the Control of Lobesia botrana (Lepidoptera: Tortricidae), a Major Pest of Grape Plants. Appl. Environ. Microbiol. 73: 337-340 [Abstract] [Full Text]  
• Ibargutxi, M. A., Estela, A., Ferre, J., Caballero, P. (2006). Use of Bacillus thuringiensis Toxins for Control of the Cotton Pest Earias insulana (Boisd.) (Lepidoptera: Noctuidae). Appl. Environ. Microbiol. 72: 437-442 [Abstract] [Full Text]