Feral genetically modified herbicide tolerant oilseed rape from seed import spills: are concerns scientifically justified?

Abstract

Contact CEH NORA team at noraceh@ceh.ac.ukThe NERC and CEH trademarks and logos ('the Trademarks') are registered trademarks of NERC in the UK and other countries, and may not be used without the prior written consent of the Trademark owner.1 | P a g e KEYWORDSGenetically modified oilseed rape, herbicide tolerance, seed spillage, ferality, persistence, invasiveness, coexistence, introgression 2 | P a g e ABSTRACTOne of the concerns surrounding the import (for food and feed uses or processing) of genetically modified herbicide tolerant (GMHT) oilseed rape is that, through seed spillage, the herbicide tolerance (HT) trait will escape into agricultural or semi-natural habitats, causing environmental or economic problems. Based on these concerns, three EU countries have invoked national safeguard clauses to ban the marketing of specific GMHT oilseed rape events on their territory. However, the scientific basis for the environmental and economic concerns posed by feral GMHT oilseed rape resulting from seed import spills is debatable.While oilseed rape has characteristics such as secondary dormancy and small seed size that enable it to persist and be redistributed in the landscape, the presence of ferals is not in itself an environmental or economic problem. Crucially, feral oilseed rape has not become invasive outside cultivated and ruderal habitats, and HT traits are not likely to result in increased invasiveness. Feral GMHT oilseed rape has the potential to introduce HT traits to volunteer weeds in agricultural fields, but would only be amplified if the herbicides to which HT volunteers are tolerant were used routinely in the field. However, this worst-case scenario is most unlikely, as seed import spills are mostly confined to port areas. Economic concerns revolve around the potential for feral GMHT oilseed rape to contribute to GM admixtures in non-GM crops. Since feral plants derived from cultivation (as distinct from import) occur at too low a frequency to affect the coexistence threshold of 0.9% in the EU, it can be concluded that feral GMHT plants resulting from seed import spills will have little relevance as a potential source of pollen or seed for GM admixture. This paper concludes that feral oilseed rape in Europe should not be routinely managed, and certainly not in semi-natural habitats, as the benefits of such action would not outweigh the negative effects of management.3 | P a g e INTRODUCTIONThe global area cropped with genetically modified (GM) crops has consistently increased each year since they were first commercially cultivated in 1996 (1.7 million hectares), reaching 148 million hectares in 2010 (James, 2010). The advent of GM crops and their rapid expansion in terms of cropping area evoked intense debate about their safety (Hails, 2000; Devos et al., 2008b;Waltz, 2009; Gaskell et al., 2011). Concerns have been raised that the commercial release of GM crops could result in adverse environmental and economic effects.Environmental concerns include the potential for altered fitness of the crop ...

Scientific Opinion on application (EFSA‐GMO‐NL‐2010‐87) for the placing on the market of genetically modified herbicide tolerant oilseed rape GT73 for food containing or consisting of, and food produced from or containing ingredients produced from, oilseed rape GT73 (with the exception of refined oil and food additives) under Regulation (EC) No 1829/2003 from Monsanto

“…The EFSA GMO Panel previously evaluated the plant-to-plant gene transfer from feral oilseed rape GT73 plants to cross-compatible plant species and the potential environmental consequences of such gene transfer (EFSA, 2004(EFSA, , 2009c Newly published data since the adoption of the 2004 EFSA GMO Panel Scientific Opinion confirm that seed dispersal is likely to occur and to result in feral GMHT oilseed rape plants in regions where GMHT oilseed rape is cultivated and/or transported (reviewed by Devos et al, 2012). In regions where GMHT oilseed rape is widely grown such as western Canada and the USA, monitoring surveys revealed the widespread occurrence of feral GMHT oilseed rape plants along field margins of agricultural fields, as well as along transportation routes (such as road verges and railway lines).…”

Scientific Opinion on application (EFSA-GMO-BE-2010-81) for the placing on the market of genetically modified herbicide-tolerant oilseed rape Ms8, Rf3 and Ms8 × Rf3 for food containing or consisting of, and food produced from or containing ingredients pro

“…Demographic studies of feral oilseed rape have shown the ability of oilseed rape to establish selfperpetuating populations outside agricultural areas, mainly in semi-natural and ruderal habitats in different countries (reviewed by Devos et al, 2012). Oilseed rape is generally regarded as an opportunistic species and can take advantage of disturbed sites due to its potential to germinate and capture resources rapidly.…”

How to track genetically modified (GM) plants in the field? The VDI standard method of floristic mapping of GM plants as an efficient tool

“…The review of Devos et al (2012) on feral GM herbicide tolerant oilseed rape from seed import spills raises the question if concerns about environmental damages are scientifically justified. The question and the attempt of an answer fail to separate scientific analysis from evaluation.…”