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ADVERSE IMPACTS OF TRANSGENIC CROPS/FOODS :A COMPILATION OF SCIENTIFIC REFERENCES WITH ABSTRACTS11. Hoss S, Arndt M, Baumgarte S, Tebbe C.C, Nguyen H.T. and Jehle J.A.(2008) : Effects of transgenic corn and Cry1Ab protein on the nematode,Caenorhabditis elegans. Ecotoxicology and Environmental Safety 70 (2) :334–340.The effects of the insecticidal Cry1Ab protein from Bacillus thuringiensis (Bt) onthe nematode, Caenorhabditis elegans, were studied with soil from experimentalûelds cultivated with transgenic Bt corn (MON810) and with trypsinized Cry1Abprotein expressed in Escherichia coli. The content of Cry1Ab protein was abovethe detection limit of an ELISA test in only half of the soil samples obtained fromtransgenic plots, ranging from 0.19 to 1.31 ng g 1dry weight. In a laboratorybioassay, C. elegans was exposed to rhizosphere and bulk soil from ûelds withisogenic or transgenic corn or to solutions of Cry1Ab protein (0, 24, 41, 63, 118,and 200 mg l1) over a period of 96 h, with growth and reproduction serving as thetest parameters. Nematode reproduction and growth were signiûcantly reducedin rhizosphere and bulk soil of Bt corn compared with soil from isogenic corn andwere signiûcantly correlated with concentrations of the Cry1Ab protein in the soilsamples. Moreover, the toxicity of pure Cry1Ab protein to the reproduction andgrowth of C. elegans was concentration-dependent. As signiûcant inhibitionoccurred at relatively high concentrations of the Cry1Ab protein (41 mg l1), theeffects of the soil samples from Bt corn could not be assigned directly to thetoxicity of the Cry1Ab protein. The results demonstrate that bioassays with thenematode, C. elegans, provide a promising tool for monitoring the potential effectsof Bt toxins in aqueous medium and soils.12. Icoz I. & Stotzky G. (2008) : Fate and effects of insect-resistant Bt crops insoil ecosystems. Soil Biology & Biochemistry 40: 559–586.Recent applications of biotechnology, especially genetic engineering, haverevolutionized crop improvement and increased theavailability of valuable newtraits. A current example is the use of the insecticidal Cry proteins from thebacterium, Bacillus thuringiensis (Bt), to improve crops, known as Bt crops, byreducing injury from various crop pests. The adoption of genetically modiûed(GM) cropshas increased dramatically in the last 11 years. However, theintroduction of GM plants into agricultural ecosystems has raised a numberofquestions, including the ecological impact of these plants on soil ecosystems.Crop residues are the primary source of carbon in soil, and root exudates governwhich organisms reside in the rhizosphere. Therefore, any change to the qualityof crop residues and rhizosphere inputs could modify the dynamics of thecomposition and activity of organisms in soil. Insect-resistant Bt crops have thepotential to change the microbial dynamics, biodiversity, and essential ecosystemfunctions in soil, because they usually produce insecticidal Cry proteins throughall parts of the plant. It is crucial that risk assessment studies on the commercialuse of Bt crops consider the impacts on organisms in soil. In general, few or notoxic effects of Cry proteins on woodlice, collembolans, mites, earthworms,nematodes, protozoa, and the activity of various enzymes in soil have been reported.Although some effects, ranging from no effect to minor and signiûcant effects, ofBt plants on microbial communities in soil have been reported, using both culturing(158)