English
Deutsch8. June 2013 Recently, a non-authorised line of genetically engineered wheat was found in a field in Oregon. Currently it is unclear why the wheat was growing there. The wheat, which proved to be Monsanto wheat MON81700, was developed in the 1990s. Monsanto, however, stopped the commercialisation process for this crop in 2004. The plants contain a gene (cp4epsps) that makes them tolerant to herbicides with glyphosate as the active ingredient. The cp4epsps gene is also present in other herbicide tolerant crops such as soybean, maize, oilseed rape or cotton.
Much of the wheat grown in the US is for export and could possibly have contaminated exports to the EU. However, as Testbiotech learned from the German Federal Ministry of Food, Agriculture and Consumer Protection (BMELV), this is a rather remote probability because wheat from Oregon is mainly exported to Asia. According to the ministry, German food authorities have nonetheless been advised to test wheat products for contamination. Such tests can be conducted throughout Europe now because Monsanto has provided European laboratories with a validated test method for the detection of MON71800.
According to the US Department of Agriculture (USDA), Monsanto conducted more than 100 field trials with glyphosate tolerant wheat in many US states between 1998 and 2005. There were also field trials in Oregon up until 2001. However, the official number of „over 100“ field trials seems to underestimate the real numer of field trials. According to USDA data, Monsanto conducted nearly 200 field trials with herbicide tolerant wheat up until 2005.
After 2005, Monsanto developed new lines of herbicide tolerant wheat and has been testing them in the field since 2011. According to several newspapers, the company conducted one field trial in Hawaii in 2011 and another in North Dacota covering a total area of 72 hectars. However, a closer look at USDA data reveals that Monsanto actually notified the planting of herbicide tolerant wheat on 280 hectares at 14 test sites.
Right now, there are no real explanations as to why the herbicide tolerant wheat has been found growing in Oregon more than ten years after field trials were stopped in this US state. However, it is probable that the wheat plants do not stem directly from the Monsanto plants that were part of the field trials. In the field trials with MON71800, the company used a summer wheat variety called Bobwhite. The plants that were found in the Oregon field were winter wheat (varieties Rod or WB528).
Some possible scenarios:
1. The genetically engineered wheat has been present in the Oregon field since the end of the Oregon field trials in 2001 and has only just germinated
This assumption is quite improbable. Firstly, according to several sources, there were no field trials in the close proximity of the Oregon field. Secondly, wheat seed rapidly looses the potential for germination under field conditions. Volunteers of glyphosate tolerant wheat have been found three years after cultivation at the maximum.
2. Outcrossing by pollen
This is also quite improbable. Outcrossing in wheat was found in up to 2.7 kilometers from the pollen sources in experiments. But in general, wheat is not a plant known for long distance pollen dispersal. Even if outcrossing should have taken place, seeds would have lost fertility in a few years time.
3. Outcrossing in wild relatives
Gene flow between wheat (Triticum aestivum) and sexually compatible wild relatives was investigated in many studies. These publications show that wheat can easily hybridise with species like Aegilops cylindrica, A. biuncialis or A. geniculata and that these hybrids remain fertile to a certain extent. So there is a very low probability that the transgene construct from MON71800 wheat introgressed in a wild relative grass, and spread in the environment.
4. Contamination of commercial seed lots
Different cases in the US and Canada show that the seed system in North America is suspectible to contamination. This leads to regular incidents of unintentional cultivation of gentically engineered plants by farmers and contamination of the food chain. Well-known cases are Starlink maize, LL601 rice, Triffid flax or Bt10 maize (see for example Friends of the Earth, 2011; Then & Stolze, 2010). So there's in fact a certain probability that MON71800 has been present in the commercial wheat seed supply for a long time and wasn't discovered simply because there were no tests. The wheat variety WB528, which possibly contained the unauthorised glyphosate tolerance gene, stems from WestBred company which belongs to Monsanto.
Regarding the food safety of MON71800, there is not enough evidence for a reasoned statement, because, according to the information available, no feeding trials were conducted. However, DNA analysis shows that MON71800 contains two copies of the cp4epsps gene construct. One of them shows significant differences to the gene cassette that was originally implanted by Monsanto. Multicopy insertion of transgene raises the probability of undesired side effects.
Sources
US Department of Agriculture, Animal and Plant Health Inspection Service, http://www.aphis.usda.gov/newsroom/2013/05/ge_wheat_detection.shtml
Friends of the Earth (2011) The socio-economic effects of GMOs: Hidden costs for the food chain. http://www.epi-gen.de/publikationen/Socio_economic_effects_gmos_FoEEbrie...
Monsanto, http://www.monsanto.com/gmwheat/Pages/default.aspx
Then, C. & Stolze, M. (2010) Seed purity: costs, advantages and risk management for markets avoiding genetically engineered plants: Economic impacts of labelling thresholds for the adventitious presence of genetically engineered organisms in conventional and organic seeds. IFOAM report. http://www.testbiotech.org/sites/default/files/IFOAM-Econimic%20impacts%...
