Toxicity of Bacillus thuringiensis CryIAb toxin to the predator Chrysoperla carnea (Neuroptera: Chrysopidae)
Authors: Hilbeck, A., Moar, W.J., Pusztai-Carey, M., Filippini, A., Bigler, F.
Journal, Volume, Year: Environmental Entomology, volume 27(5): 1255-1263, 1998
Laboratory feeding studies were conducted to determine effects of Cry1Ab toxin on developmental time and mortality of Chrysoperla carnea larvae. Cry1Ab toxin (100 ug/ml of diet) was incorporated into a liquid diet that was encapsulated within small paraffin spheres. After reaching the 2nd instar, all larvae received the encapsulated artificial diet with or without CryIAb toxin. Mortality was higher in C. carnea fed the CryIAb-treated diet compared to the control. However, no or only small differences in developmental time were observed in C. carnea fed CryIAb-treated and untreated diets.
Although significant mortality of Chrysoperla carnea occurred in this study, extremely high concentrations of pure Cry1Ab protein in an artificial diet were used (100 ug/ml of diet). In addition, the lack of quantification of Bt consumption by C. carnea does not allow the authors to determine correlation between exposure to Bt and observed responses.