Entomologia Experimentalis et Applicata (2009) 131, 308-319

Michael Meissle and Jörg Romeis (2009)
Insecticidal activity of Cry3Bb1 expressed in Bt maize on larvae of the Colorado potato beetle, Leptinotarsa decemlineata
Entomologia Experimentalis et Applicata 131 (3), 308-319
Abstract: Environmental risk assessment for genetically modified crops producing insecticidal Cry proteins derived from Bacillus thuringiensis (Bt) includes the evaluation of adverse effects on non-target organisms. Although ELISA concentration measurements indicate the presence of Cry proteins, sensitive insect bioassays determine whether there is biological activity. The insecticidal activity of the coleopteran-active Cry3Bb1 expressed in different tissues of Bt maize, contained in maize-fed herbivores, and in spiked soil was measured in sensitive insect bioassays using larvae of the Colorado potato beetle, Leptinotarsa decemlineata (Say) (Coleoptera: Chrysomelidae). Biological activity was confirmed of Cry3Bb1 contained in pulverized Bt maize pollen, roots, leaves, silk, and Bt maize-fed spider mites and western corn rootworm adults. When test substances were incorporated into artificial diet at the same concentrations of Cry3Bb1 (measured by ELISA), maize pollen and leaf litter exhibited lower toxicity than fresh plant material and maize-fed arthropods. This suggests that nutritional quality of food and degradation of Cry proteins may influence toxicity to insects. When soil was spiked with Cry3Bb1, the Bt protein was highly adsorbed and retained its full biological activity. Because toxicity of Cry proteins contained in different matrices cannot always be determined from ELISA values alone, sensitive insect bioassays can improve hazard and exposure assessments in environmental risk assessment of Bt crops.
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Link to article at publishers website
Database assignments for author(s): Michael Meissle, Jörg Romeis

Research topic(s) for pests/diseases/weeds:
biocontrol - natural enemies
Research topic(s) for beneficials or antagonists:
non-target effects/fate in environm.

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Leptinotarsa decemlineata
Bacillus thuringiensis genes in crops (entomopathogen)
Bacillus thuringiensis Cry3B-toxin (entomopathogen)	Leptinotarsa decemlineata