This paper is relevant to the impact areas in the following areas:
| Crops | Maize |
| Traits | Insect Res. (BT), Insect Resistance |
| Countries | Germany |
| Regions | Europe |
| Tags | environmental, non-targets |
Concerns have been raised that genetically modified Bt maize may harm non-target organisms, and there is a general call and need for a risk assessment of Bt maize. Spiders are important pest predators in agroecosystems and in maize, and can be exposed to the Bt toxin by herbivorous or pollen-collecting prey, by active Bt maize pollen feeding, and by ingesting their pollen-dusted webs. The foliage-dwelling spider fauna of Bt maize fields and adjacent margins was monitored and compared to non-transgenic maize fields. The study took place during the vegetation seasons of 2001–2003 in Bavaria, South Germany. Maize Welds and adjacent nettle field margins were colonized by a typical spider assemblage, dominated by space-web spiders (Theridiidae and Linyphiidae). Abundance and species richness of spiders was higher in nettle margins than in maize fields. The proportion of hunting spiders tended to be higher in nettle margins, whereas space-web spiders tended to be more frequent in maize fields. Bt maize showed no consistent effect on individual numbers, species richness and guild structure of spiders in maize fields and adjacent nettle field margin strips. The spider abundance was higher in Bt treatments in 2003, whereas in 2001 and 2002 no significant differences were found. The results provide an important contribution for the implementation of case-specifc and general surveillance of transgenic plants to be employed due to the regulations of the European Community.
A 3-year Weld-scale monitoring of foliage-dwelling spiders (Araneae) in transgenic Bt maize Welds and adjacent field margins (held on an external server, and so may require additional authentication details)
CropLife International fully acknowledges the source and authors of the publication as detailed above.