Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-11-19T20:52:05.003Z Has data issue: false hasContentIssue false

Response to comments by DiGiovanni and Kevan on “Session V: Estimating Likelihood and Exposure”,by Zaida Lentini, Environ. Biosafety Res. 5 (2006) 193–195

Published online by Cambridge University Press:  13 June 2008

David I. Gustafson*
Affiliation:
Monsanto Company, 800 North Lindbergh Blvd, St. Louis, MO, 63167, USA

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

DiGiovanni and Kevan (2008, Environ. Biosafety Res.7: 105–108) commented extensively on the empirical approach that I and my co-authors took in our previous modeling of pollen-mediated gene flow in maize (Gustafson et al. (2006) Crop Sci.46: 2133–2140). As we detailed in that original paper, gene flow is a highly complex process that necessarily requires at least some level of empiricism in order to adequately quantify all of the biological, meteorological, and physical phenomena that are involved. DiGiovanni and Kevan favor a mechanistic modeling approach, and they proposed a number of potential advantages for such a method over our entirely empirical technique. However, the 20 m buffers we had proposed based on our empirical model continue to be supported by the rapidly growing body of experimental data on maize gene flow that has now been collected in Europe and elsewhere around the world. This does not mean there is no place for mechanistic modeling of gene flow, but it does suggest that properly implemented empirical approaches have a valid role to play. They offer a degree of simplicity and practical utility that is not available from more complicated approaches.


Type
Research Article
Copyright
© ISBR, EDP Sciences, 2008

References

Bannert M (2006) Simulation of transgenic pollen dispersal by use of different grain colour maize. Dissertation no. 16508. Swiss Federal Institute of Technology of Zürich. http://www.agrisite.de/doc/ge_img/pollen-swiss.pdf
Bannert, M, Stamp, P (2007) Cross-pollination of maize at long distance. Eur. J. Agron. 27: 4451 CrossRef
Bénétrix F (2005) Managing the coexistence of conventional and genetically modified maize from field to silo – a French initiative. Proceedings of the 2nd International conference on coexistence between GM and non-GM based agricultural supply chains, GMCC-05, 14–15 November 2005, Montpellier, France
Byrne PF, Gaines TA, Meyer RF, Alexander R (2007) Estimating pollen-mediated gene flow in Colorado corn fields with the blue kernel trait. Proceedings of the Gene Flow Symposium of the North Central Weed Science Society Annual Meeting, St. Louis, MO, Dec. 13–14, 2007
Della Porta G, Ederle D, Bucchini L, Prandi M, Pozzi C, Verderio A (2006) Gene flow between neighboring fields in the Po Valley. Publication of the Centro di Documentazione Agrobiotecnologie (CEDAB). http://www.cedab.it
Devos, Y, Reuhel, D, De Schrijver A (2005) The co-existence between transgenic and non-transgenic maize in the European Union: a focus on pollen flow and cross-fertilisation. Environ. Biosafety Res. 4: 7187 CrossRef
DiGiovanni F, Kevan PG (2008) Comment on “Session V: Estimating Likelihood and Exposure”. Environ. Biosafety Res. 7: 105–108
Goggi, AS, Caragea, P, Lopez-Sanchez, H, Westgate, M, Arritt, R, Clark, C (2006) Statistical analysis of outcrossing between adjacent maize grain production fields. Field Crops Res. 99: 147157 CrossRef
Gustafson, DI, Brants, IO, Horak, MJ, Remund, KM, Rosenbaum, EW, Soteres, JK (2006) Empirical modeling of genetically-modified maize grain production practices to achieve European Union labeling thresholds. Crop Sci. 46: 21332140 CrossRef
Joint Research Centre (2006) New case studies on the coexistence of GM and non GM crops in European agriculture. Eur 22102, JRC, IPTS Technical Report Series
Langhof, M, Hommel, B, Hüsken, A, Schiemann, J, Wehling, P, Wilhelm, R, Rühl, G (2008) Coexistence in maize: do nonmaize buffer zones reduce gene flow between maize fields? Crop Sci. 48: 305316 CrossRef
Messeguer J, Peñas G, Ballester J, Bas M, Serra J, Salvia J, Palaudelmàs M, Melé E (2006) Pollen-mediated gene flow in maize in real situations of coexistence. Plant Biotech. J. 4: 633–645
Ortega Molina J (2006) The Spanish experience with co-existence after 8 years of cultivation of GM maize. Proceedings of the Co-existence of GM, conventional and organic crops, Freedom of Choice Conference, Vienna, April 2006
Weber, WE, Bringezu, T, Broer, I, Holz, F, Eder, J (2006) Coexistence between GM and non-GM maize crops – tested in 2004 at the field scale level (Erprobungsanbau 2004). J. Agron. Crop Sci. 193: 7992 CrossRef
Weekes, R, Allnutt, T, Boffey, C, Morgan, S, Bilton, M, Daniels, R, Henry, C (2007) A study of crop-to-crop gene flow using farm scale sites of fodder maize (Zea mays L.) in the UK. Transg. Res. 16: 203211 CrossRef