Bacterial communities influenced by transgenic plants

摘要

Field releases of transgenic sugar beet and potato plants in Germany in 1993 and 1994 were accompanied by research on potential effects of the transgenic plants on plant associated and soil bacteria. The objective of the studies was to deliver fielddata on the persistence of transgenic Agrobacterium tumefaciens in the released plants, on the persistence of transgenic plant DNA in the soil of the release site, and on horizontal gene transfer. Screening of plant material taken from the release siteby selective cultivation followed by molecular analysis revealed no indication for persisting agrobacteria in the sugar beet and potato plants tested. Analysis of DNA extracted directly from soil samples by polymerase chain reaction (PCR) showed a long-term persistence of transgenic plant DNA in soil samples collected at the disposal area. However, none of the more than 2,000 kanamycin (Km)-resistant bacteria screened for the presence of the construct by dot blot hybridizations contained the transgenicplant DNA. Furthermore, data from a study on the natural occurrence of the nptll gene and Tn5 will be discussed.