German Federal Agency for Nature Conservation (BfN)


Risk Assessment Requirements Concerning Deliberate Release of Genetically Modified Trees and Shrubs


Integration of nature conservation issues into genetic engineering policy

Research Code

201 67 430/02

Project Lifecycle

1 April 2001 – 30 June 2004

Research Focus and Aims


The aim of this three-year collaborative project was to improve the conditions for risk assessment in the deliberate release and placing on the market of genetically modified trees and shrubs. The transfer of genes from transgenic trees and shrubs to wild types could put natural ecosystems at risk. To assess the risk, it is necessary to identify the scope and frequency of the transfer. Little experience has been gathered in this area to date. Producing sterile plants acts as a safety measure to prevent the transfer of transgene trees and shrubs to wild types. One problem that remains unsolved is ongoing and stable expression of the sterility trait.

The project's first area of focus is thus to analyse available knowledge on the stability and/or instability of transgenes in trees and shrubs. A study of the literature at the start of the project showed that little knowledge is available on this issue globally.

Finally, a study was conducted on the expression of specific transgene constructs in the tree and shrub species aspen, larch, silver fir, Nordmann fir, rhododendron and rose under comparable environmental conditions achieved in climate chambers (no stress, or with UV and temperature stress) to allow conclusions to be drawn on the impact on gene stability and expression in various tree and shrub species. For the first time in a collaborative project, six tree and shrub species were studied for transgene stability. Under varying environmental conditions (with and without stress), more than 1,000 plants and over 5,000 embryos were used in trials conducted on gene constructs containing the same reporter gene (uidA) with the same promotor (S35). Another gene construct (rbcS-uidA) was tested in aspen.

The second main area of focus is the experimental analysis and modelling of gene flow. Parallel studies were conducted on the transfer in the open environment of two different non-transgenic tree and shrub species (aspen and rhododendron) using molecular markers. Gene flow models for transgenic trees are used first to gain knowledge on the dispersal potential and then to devise appropriate safety measures. In a sub-project, an 'Introgression' simulation model was developed and used to demonstrate dispersal of aspen pollen in open landscapes.

Research Body

Project Manager
Ministerium für Umwelt, Naturschutz und Landwirtschaft des Landes Schleswig-Holstein, Dr. Thomas Engelke

Project Participants
BioTechConsult Berlin, AG Dr. Pickardt/de Kathen
Bundesanstalt für Züchtungsforschung (Institut für Zierpflanzenzüchtung, Ahrensburg), AG Dr. Debener und AG Dr. Dunemann
Bundesforschungsanstalt für Forst- und Holzwirtschaft (Institut für Forstgenetik und Forstpflanzenzüchtung, Großhansdorf), AG Dr. Fladung
Humboldt-Universität Berlin (Institut für Biologie), AG Dr. Zoglauer
Phillips Universität Marburg (Fachbereich Biologie), AG Prof. Ziegenhagen
Universität Hamburg (Meteorologisches Institut), AG Prof. Schlünzen

Point of Contact at BfN

Hanka Teichmann FG II 2.3

Last Change: 05/07/2006