Abstract
Propagule flow in populations of virtually all organisms has importance for both the genetic cohesion of the species and for its interaction with natural selection. It’s relevance` for the deployment of genetically modified organisms (GMOs) is that propagules can be expected to move, under a wide range of circumstances, and will carry transgenic elements with them. Any consideration of the potential risks of deploying GMOs in the wild must include an assessment of how far and how fast introduced elements are transferred to surrounding conspecific (and sometimes congeneric) populations. In practice, we need estimates of the rates/distances of both pollen and seed movement. There are analytical methods to characterize seed (maternity), pollen (paternity), and established offspring (parent-pair) data, but spatial limitations restrict the area that one can study, and these approaches require modification for application to propagule flow in GMOs. We can apply indirect methods to estimate male gamete dispersal based on pollen pool analysis for single mothers, when some degree of precision can be sacrificed in return for compensating gains in the spatial coverage, but the loss of precision is problematic for GMO tracking. Special methods have been developed for GMO tracking, and we shall show how to assess spatial movement of both transgene-carrying seeds and pollen and will illustrate with an example from Brassica napus, a well-studied crop species.
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Acknowledgements
The authors wish to thank Fred Austerlitz, Eva Gonzales, Victoria Sork, B Wang, and a trio of anonymous reviewers for many helpful comments on the manuscript. PES was supported by USDA/NJAES-17111 and by NSF-DEB-0211430 and NSF-DEB-0514956; JJR-A was supported by a postdoctoral fellowship from the Spanish Secretaría de Estado de Educación y Universidades, financed in part by the European Social Fund; SCG-M was supported by the ‘Ramón y Cajal’ fellowship RC02-2941 and by AGL2005-07440-C02-01 grant (Ministerio de Educación y Ciencia, Spain).
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Communicated by Ronald Sederoff
Institute of Forest Biotechnology conference on Ecological Risks Associated with the Products of Forest Biotechnology
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Smouse, P.E., Robledo-Arnuncio, J.J. & González-Martínez, S.C. Implications of natural propagule flow for containment of genetically modified forest trees. Tree Genetics & Genomes 3, 141–152 (2007). https://doi.org/10.1007/s11295-006-0075-8
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DOI: https://doi.org/10.1007/s11295-006-0075-8