National research projects have been conducted to investigate out-crossing rates of some transgenic crops. Publicly funded research projects on issues relevant to co-existence have been conducted since 1999. Researchers measured pollen flow from GM maize into surrounding fields, determining minimum distances for preventing cross-pollination with conventional or organic fields, and considering relevant parameters like field size and wind direction.
During the test planting of GM maize in 2004, scientists at the University of Halle took samples from neighbouring conventional maize fields in various distances. The evaluation of the experiments showed that the share of GMOs in the conventional maize quickly decreases with increasing distance. At a distance of 10 metres, most maize samples contained GMO shares below the labelling threshold of 0.9 percent. With high confidence, maize at 20 metres from GM plantings will not require labelling. These results have become the basis for the codes of Good Farming Practice that seed companies provide to farmers as of 2005. The documentation is available in German at www.transgen.de (grain maize and forage maize).
The test planting in 2005 was coordinated by scientists of the University of Rostock. In contrast to the test planting in 2004, they designed experiments for several plant species to find out if plants like grasses, barley, potatoes, or fallows can serve as buffer zones for maize pollen. The final results have not yet been published. However, it has already become clear that conventional maize is a more effective at stopping the spread of GM than buffer strips with other crops. In contrast to the analyses in 2004, 2005’s preliminary findings seem to suggest that GM content above the labelling threshold of 0.9 percent can be found at distances of more than 20 metres downwind of the GM planting. However, samples were taken directly from the rows themselves, not from the entire harvest batch. What really matters is the GM content in the entire batch when the grain from the entire field is harvested together. Again, the documentation is available in German at www.transgen.de.
In parallel to the test plantings of 2004 and 2005, scientists in Bavaria conducted experiments on the co-existence of Bt maize cultivation and the production of honey. They placed bee colonies at various distances from Bt maize fields and analysed both the honey the pollen carried by the bees for potential traces of GM maize. The result: Only very slight traces Bt maize were found in the honey. The amounts were too small to be quantified precisely. In the collected pollen the scientists sometimes found Bt maize shares above 0.9 percent – but only if the bee populations had been placed directly besides Bt maize fields. Further information is available in German at www.transgen.de (2004 and 2005).
In 2005, scientists from the Federal Agricultural Research Centre (FAL) have started their own cultivation trials on co-existence commissioned by the Federal Ministry of Agriculture (BMELV). Similar to the test plantings, the main goal of the experiments is to identify minimum separation distances and other suitable measures for the co-existence of genetically modified and conventional maize in the same vicinity. In addition, the researchers aim to analyse the impact of clover/grass mixtures and crop stubbles as separation areas. A third aspect of the studies is the question of whether or not the direction of the maize rows relative to prevailing winds has a role in out-crossing rates. In 2006 the focus was on realistic cultivation trials at six locations. In 2007 the previous year's trials were repeated using an almost identical trial set-up.
More information on the trials in 2005 and 2006:
"Over the next few years our aim is to make our trials as realistic as possible." Gerhard Rühl talks about the BMELV coexistence research programme 2005.
BMELV coexistence research programme 2006: locations, experimental design and research questions
The Federal Ministry of Education and Research (BMBF) funded research on maize out-crossing between 1999 and 2002. The experiments sought to identify the frequency of out-crossing from Bt maize into conventional cultivars depending on various conditions such as weather and prevailing winds. The studied were also intended to help establish co-existence measures. The research programme was conducted by the Federal Biological Research Centre (BBA).
Among the results from this project was the conclusion that the presence of GM pollen drops off quickly with increasing distance from the GM maize field, both in the direction of and against prevailing winds. On average, out-crossing was twice as frequent downwind from the GM field than upwind.
At a distance of ten metres from the GM field, the frequency of out-crossings stayed below one percent on average. At distances of 25 metres, individual measurements were found above one percent, and at 50 metres, out-crossing always remained below one percent. Thus the BBA researchers created a set of basic data which has been largely confirmed by later projects like the test cultivations in 2004. The results are available at www.gmo-safety.eu (documentation and report).
In coorporation with the technical service provider TÜV Nord, the feed company Märka has developed a standard procedure for separating the commodity flows of genetically modified and conventional grain maize.
The goal is to collect and process conventional maize and maize requiring labelling separately. For the system to function the farmers planning to grow GM maize must inform the maize-growing neighbours of their plans. Conventional maize growers with fields less than 20 metres away from GM maize fields must share this with Märka. Once their harvest reaches Märka, this maize is merged with GM maize harvests. When the grain maize is dried during processing, the machine is flushed out with conventional maize after the machine is done with the GM maize, and the first batch of conventional maize is sold as GM. To evaluate the success of the separation system, samples were taken from all incoming maize loads and from points further along in processing in 2005. The analyses showed that the maize harvested more than 20 metres away from GM maize fields consistently stayed well below the 0.9 percent labelling threshold – that is if farmers comply with the seed companies’ codes of Good Farming Practice. Therefore, the system for separation has stood the test. The results are available in German at www.transgen.de.
Since no genetically modified rapeseed varieties have been approved for cultivation in the EU, there is no practical experience on the co-existence of genetically modified and conventional rapeseed, neither in Germany nor in other EU member states. Nonetheless, between 1999 and 2004 several research projects with GM rapeseed have been conducted in Germany in the framework of biosafety research, in which questions of relevance to co-existence have been studied. Several universities and research institutions were involved with a joint research programme investigating the spread of genetically modifed rapeseed.
The results: Unlike maize pollen, rapeseed pollen is spread mainly by bees. They can carry rapeseed pollen for several kilometres. However, the amount of rapeseed pollen decreases rapidly with increasing distance. In addition, only part of the transported rapeseed pollen actually fertilises conventional rapeseed plants. Above a field size of 15 hectares, the outcrossing from neighbouring GM fields remained below 0.5 percent.
Rapeseeds that fall to the ground during harvest can germinate the following years thereby spreading both conventional and genetically modified rapeseed plants. Thoroughly cultivating the soil reduces the number of these so-called volunteers significantly. Volunteer rapeseed can persist in agricultural fields and even in the wild, but never to a great extent. Further information is available at www.gmo-safety.eu.
Reliable and standardised detection systems are the basis for monitoring compliance with regulations on co-existence, labelling, and traceability. Detection methods are standardised for individual GM plant varieties at the EU level. This was made possible by testing activities in several different countries. The Federal Office of Consumer Protection and Food Safety (BVL) in Berlin coordinates monitoring activities in Germany and is also involved in the development of detection methods. The European Regulation regarding the Community reference laboratory for genetically modified organisms lists a total of 20 German national reference laboratories assisting in the testing and validation of methods for GMO detection.