Decomposition dynamics and structural plant components of genetically modified <Emphasis Type="Italic">Bt</Emphasis> maize leaves do not differ from leaves of conventional hybrids |
| |
Authors: | Corinne Zurbrügg Linda Hönemann Michael Meissle Jörg Romeis Wolfgang Nentwig |
| |
Institution: | 1.Institute of Ecology and Evolution,University of Bern,Bern,Switzerland;2.Agroscope Reckenholz-T?nikon Research Station ART,Zurich,Switzerland;3.AGRIDEA,Lindau,Switzerland |
| |
Abstract: | The cultivation of genetically modified Bt maize has raised environmental concerns, as large amounts of plant residues remain in the field and may negatively impact
the soil ecosystem. In a field experiment, decomposition of leaf residues from three genetically modified (two expressing
the Cry1Ab, one the Cry3Bb1 protein) and six non-transgenic hybrids (the three corresponding non-transformed near-isolines
and three conventional hybrids) was investigated using litterbags. To elucidate the mechanisms that cause differences in plant
decomposition, structural plant components (i.e., C:N ratio, lignin, cellulose, hemicellulose) were examined. Furthermore,
Cry1Ab and Cry3Bb1 protein concentrations in maize leaf residues were measured from harvest to the next growing season. While
leaf residue decomposition in transgenic and non-transgenic plants was similar, differences among conventional cultivars were
evident. Similarly, plant components among conventional hybrids differed more than between transgenic and non-transgenic hybrids.
Moreover, differences in senescent plant material collected directly from plants were larger than after exposure to soil for
5 months. While the concentration of Cry3Bb1 was higher in senescent maize leaves than that of Cry1Ab, degradation was faster,
indicating that Cry3Bb1 has a shorter persistence in plant residues. As decomposition patterns of Bt-transgenic maize were shown to be well within the range of common conventional hybrids, there is no indication of ecologically
relevant, adverse effects on the activity of the decomposer community. |
| |
Keywords: | |
本文献已被 SpringerLink 等数据库收录! |
|