Transgenic Research

, Volume 12, Issue 6, pp 731–737 | Cite as

Predicting the Spread of Herbicide Resistance in Australian Canola Fields



A common concern expressed about the commercial release of transgenic canola into cropping systems is the risks of unwanted gene flow between varieties. Experimental data is emerging that answers some of the theoretical questions that have been posed when considering gene flow on a landscape scale. This study developed models that utilise some of this published data in an attempt to quantify the spread of transgenes in a commercial farming system. The models, which included bootstrapping the empirical data and three mathematical simulations, were compared with each other and the published data. One of the mathematical models estimated average resistance frequency by imposing a Poisson distribution around the published mean value for a single transgenic field surrounded by conventional canola fields and the other two were derived from the theory that pollen flow decreased with distance in the form of a log decay curve. The predictions of all models suggested that the average frequency of resistance occurring from pollen flow in neighbouring canola fields, even when multiple transgenic fields are adjacent to the conventional fields, are likely to be below the current internationally accepted thresholds for contamination.

commercial canola gene flow herbicide resistance mathematical model transgene 


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  1. Colbach N, Clermont-Dauphin C et al. (2001a) GeneSys: a model of the influence of cropping system on gene escape from herbicide tolerant rapeseed crops to rape volunteers. I. Temporal evolution of a population of rapeseed volunteers. Agric Ecosyst Environ 83: 235–253.Google Scholar
  2. Colbach N, Clermont-Dauphin C et al. (2001b) GeneSys: a model of the influence of cropping system on gene escape from herbicide tolerant rapeseed crops to rape volunteers. II. Genetic exchanges among volunteer and cropped populations in a small region. Agric Ecosyst Environ 83: 255–270.Google Scholar
  3. Lavigne C, Godelle B et al. (1996) A method to determine the mean pollen dispersal of individual plants growing within a large pollen source. Theor Appl Genet 93: 1319–1326.Google Scholar
  4. Lavigne C, Klein EK et al. (1998) A pollen-dispersal experiment with transgenic oilseed rape. Estimation of the average pollen dispersal of an individual plant within a field. Theor Appl Genet 96: 886–896.Google Scholar
  5. Maxwell BD, Roush ML et al. (1990) Predicting the evolution and dynamics of herbicide resistance in weed populations. Weed Technol 4: 2–13.Google Scholar
  6. McCartney HA, Lacey ME (1991) Wind dispersal of pollen from crops of oilseed rape (Brassica napus L.). J Aerosol Sci 22: 467–477.Google Scholar
  7. Rakow G, Woods DL (1987) Outcrossing in rape and mustard under Saskatchewan (Canada) prairie conditions. Can J Plant Sci 67: 147–152.Google Scholar
  8. Richter O, Boettcher U et al. (2000) Modelling of spatial spread of herbicide resistance. Zeitschrift-fuer-Pflanzenkrankheiten-und-Pflanzenschutz. (Special Iss. 17): 329–336.Google Scholar
  9. Rieger MA, Lamond M et al. (2002) Pollen-mediated movement of herbicide resistance between commercial canola fields. Science 296: 2386–2388.Google Scholar
  10. Scheffler JA, Parkinson R et al. (1993) Frequency and distance of pollen dispersal from transgenic oilseed rape (Brassica napus). Transgenic Res 2: 356–364.Google Scholar
  11. Scheffler JA, Parkinson R et al. (1995) Evaluating the effectiveness of isolation distances for field plots of oilseed rape (Brassica napus) using a herbicide-resistance transgene as a selectable marker. Plant Breed 114: 317–321.Google Scholar
  12. Snow AA, Moran-Palma P (1997) Commercialization of transgenic plants: potential ecological risks. Bioscience 47: 86–96.Google Scholar
  13. Squire GR (1999) Temperature and heterogeneity of emergence time in oilseed rape. Ann Appl Biol 135: 439–447.Google Scholar
  14. Squire GR, Burn D et al. (1997) A model for the impact of herbicide tolerance on the performance of oilseed rape as a volunteer weed. Ann Appl Biol 131: 315–338.Google Scholar
  15. Staniland BK, McVetty PBE et al. (2000). Effectiveness of border areas in confining the spread of transgenic Brassica napus pollen. Can J Plant Sci 80: 521–526.Google Scholar
  16. Thompson CE, Squire G et al. (1999) Regional patterns of gene flow and its consequences for GM oilseed rape. Gene Flow and Agriculture. Relevance for Transgenic Crops. BCP Council, University of Keele, Staffordshire.Google Scholar

Copyright information

© Kluwer Academic Publishers 2003

Authors and Affiliations

  1. 1.Department of Applied and Molecular Ecology, Cooperative Research Centre for Australian Weed ManagementUniversity of Adelaide, PMB 1Glen OsmondAustralia

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