testing pollen of single and stacked insect-resistant bt-maize on in vitro reared honey bee larvae测试单并把抗虫玉米堆在体外花粉饲养蜜蜂幼虫.pdf

Testing Pollen of Single and Stacked Insect-Resistant Bt- Maize on In vitro Reared Honey Bee Larvae ¨ Harmen P. Hendriksma*, Stephan Hartel, Ingolf Steffan-Dewenter ¨ ¨ Department of Animal Ecology and Tropical Biology, Biocentre, University of Wurzburg, Wurzburg, Germany Abstract The ecologically and economic important honey bee (Apis mellifera) is a key non-target arthropod species in environmental risk assessment (ERA) of genetically modified (GM) crops. Honey bee larvae are directly exposed to transgenic products by the consumption of GM pollen. But most ERA studies only consider responses of adult bees, although Bt-proteins primarily affect the larval phases of target organisms. We adopted an in vitro larvae rearing system, to assess lethal and sublethal effects of Bt-pollen consumption in a standardized eco-toxicological bioassay. The effects of pollen from two Bt-maize cultivars, one expressing a single and the other a total of three Bt-proteins, on the survival and prepupae weight of honey bee larvae were analyzed. The control treatments included pollen from three non-transgenic maize varieties and of Heliconia rostrata. Three days old larvae were fed the realistic exposure dose of 2 mg pollen within the semi-artificial diet. The larvae were monitored over 120 h, until the prepupal stage, where larvae terminate feeding and growing. Neither single nor stacked Bt-maize pollen showed an adverse effect on larval survival and the prepupal weight. In contrast, feeding of H. rostrata pollen caused significant toxic effects. The results of this study indicate that pollen of the tested Bt-varieties does not harm the development of in vitro reared A. mellifera larvae. To sustai