There are currently 402 studies in the GENERA database.

Advanced Search

General Information

Document type
  • Peer-reviewed journal article
GE trait
  • insect resistance
Country
  • Switzerland

Results

Safety for environment
  • mixed

Effects of activated Bt transgene products (Cry1Ab, Cry3Bb) on immature stages of the ladybird Adalia bipunctata in laboratory ecotoxicity testing

Schmidt, JE; Braun, CU; Whitehouse, LP; Hilbeck, A
Archives of Environmental Contamination and Toxicology. 2009 February. 56(2):221-228

Link to full text (journal may charge for access)

PMID: 18712501 DOI: 10.1007/s00244-008-9191-9 ISSN: 1432-0703

Abstract

Insect-active Bacillus thuringiensis (Bt) proteins are expressed by several transgenic crop plants to control certain pests, but nontarget organisms such as ladybirds also can be exposed to these proteins in the field. We developed an improved ecotoxicity testing protocol and conducted feeding trials in a laboratory setting to test for possible adverse effects of different concentrations of microbially produced trypsin-activated Cry1Ab and Cry3Bb toxins on the coccinellid Adalia bipunctata. Larval/pupal mortality, development time, and overall body mass accumulation were recorded. Even at the lowest concentration (5 microg/ml), A. bipunctata larvae fed with the lepidopteran-active Cry1Ab toxin exhibited significantly higher mortality than the control group. In experiments with the coleopteran-active Cry3Bb, only a concentration of 25 microg/ml resulted in a marginally significantly higher mortality compared to the control. Both experiments revealed a slight decline in mortality at the highest concentration of 50 microg/ml, though this was statistically significant only in the Cry1Ab treatment. No differences were detected for development time and body mass of newly emerged adults. Dilutions of the expression vector pBD10--used as a control to exclude effects of the toxin production method--at concentrations between 10 and 100 microg/ml revealed no significant effects on either of the studied parameters. This suggests that the increased mortality of larvae in the toxin feeding trials was caused directly by the activated Bt toxins and raises questions regarding their commonly postulated specificity and their mode of action in A. bipunctata. Implications of the reported results for ladybird populations and their biological pest control functions in transgenic crop ecosystems are discussed.

Keywords

Bt; ladybird; ladybug; larvae; feeding trial; Cry1Ab; Cry2Bb

Funding

Funding source
  • European Commission
Funding country
  • European Union
Funding type
  • government

Links to outside analysis of this resource

Please contact us if you know of an independent summary or analysis of this resource.

Cite this study

MLA

Schmidt, JE, CU Braun, LP Whitehouse, A Hilbeck. "Effects of activated Bt transgene products (Cry1Ab, Cry3Bb) on immature stages of the ladybird Adalia bipunctata in laboratory ecotoxicity testing." Archives of Environmental Contamination and Toxicology 56.2 (2009): 221-228. Web. 18 Jul. 2018.

APA

Schmidt, JE., Braun, CU., Whitehouse, LP., & Hilbeck, A. (2009). Effects of activated Bt transgene products (Cry1Ab, Cry3Bb) on immature stages of the ladybird Adalia bipunctata in laboratory ecotoxicity testing. Archives of Environmental Contamination and Toxicology, 56(2), 221-228. doi:10.1007/s00244-008-9191-9

Please verify citations before use, citations are automatically generated based on information stored within the GENERA database and therefore may or may not be correct.