Feb 4, 2011
Research Institute of Organic Agriculture:
Genetically modified Bt maize does not affect soil fertility
A team at the Swiss Research Institute of Organic Agriculture (FiBL) in Frick has established during greenhouse trials that the genetically modified Bt maize used in their experiments does not diminish soil fertility. This project is part of the Swiss national research programme on the benefits and risks of releasing GM crops (NFP 59). Since the NFP 59 trials conducted with GM wheat have not revealed any ecological risks either, the debate about continuing the Swiss ban on genetic engineering is intensifying.
Maize in the greenhouse
The Swiss national research programme NFP 59 involves 29 projects. The focus is on field trials with genetically modified wheat. Other projects are also looking at socioeconomic issues, including coexistence of GM and conventional crops. There are plans to publish a final report on these projects in summer 2011.
The research group led by Paul Mäder wanted to find out whether Bt maize has a negative impact on soil fertility. Soil micro-organisms break down plant material, thereby releasing plant nutrients. If Bt maize or the Bt protein it contains were to affect the soil micro-organisms, it could lead to a decline in soil fertility.
To test this hypothesis, the scientists planted Bt maize and conventional maize in the greenhouse and then analysed the bacterial diversity, the released nutrients and the breakdown rate for plant remains in the soil. They found that there was no difference between the Bt maize and the conventional maize. The type of soil used in the greenhouse did not affect the results either. The Bt maize had no impact on soil fertility compared with conventional maize, regardless of whether the soil had come from organic fields or conventional fields.
According to Mäder, the results cannot, however, be applied automatically to other Bt maize plants. Seed producers like Syngenta and Monsanto did not provide FiBL with recent seed. The Bt maize used in the trial was therefore a first-generation GM variety and contains a lower quantity of Bt than today’s Bt maize plants.
The experiments were conducted as part of the Swiss national research programme on the benefits and risks of releasing GM crops (NFP 59). The team has since submitted the results for publication in a scientific journal.
The NFP 59 programme released the results of two more trials with GM wheat last week. No negative effects on the ecosystem were found in these either. Against this background, the debate about the Swiss ban on genetic engineering, which runs out in 2013, is intensifying. Lieni Füglistaller, the SVP member of the Swiss National Council for Aargau, who is also President of the National Council’s Scientific Commission (WBK), does not see how the ban can be extended in view of the positive research results. According to Füglistaller, the National Council will have to decide now whether it is in favour of or against genetic engineering.
The Research Institute of Organic Farming, which conducted the maize trials on soil fertility, assesses the situation very differently. According to a FiBL press release, the results of the trial do not represent a clean bill of health for genetic engineering. Urs Niggli, FiBL’s Director, said that genetic engineering must be evaluated taking into account the sustainable development of Swiss agriculture and its quality strategy. Genetically modified plants were not, he claimed, an option in Switzerland’s fragmented farming landscape, where it was not possible to guarantee the coexistence of GM and conventional crops or to ensure freedom of choice for consumers. This was something else that FiBL research projects conducted as part of the NFP 59 programme had demonstrated. In addition, he said, the GM plants available today did not offer ecological or economic advantages for Swiss agriculture.