Expert response from Dr. L. Curtis Hannah
Professor, University of Florida
Wednesday, 09/04/2013 15:14
First, thank you very much for your series of questions. In terms of regulatory issues for releasing transgenic cultivars that are hybrid (such as corn or maize), versus, I assume, ones that are not (such as soybeans), there are no formal differences in the regulatory process. Questions concerning the nature of the gene, its function, its insertion site in the host genome, effect on plant growth and composition, allergenic properties of the added protein, etc., must be satisfied before the transgene can be “deregulated” and used commercially.
Your question may be getting at the fact that we normally associate hybrid commercial plants with ones that normally outcross in nature, versus ones that normally self-pollinate. In corn, for example, the female and male flowers are separate and pollen from one plant will commonly pollinate an egg born on a different plant. In contrast, soybeans and many other plants have perfect flowers, and the amount of “outcrossing” in male-fertile soybeans is virtually zero. Soybean seeds result from a fusion of a sperm and egg produced on the same plant.
The distance of pollen flow and rates of outcrossing are considered in testing of regulated, experimental transgenic plants not yet commercialized. In corn, for example, experimental transgenic corn must be separated by 660 feet from other conventional corn. This distance greatly minimizes the amount of transgenic pollen fertilizing neighboring corn.
Questions of liability of transgenic crops are complex, and I refer you to a nice overview by Drew Kershen, 2004, Crop Science volume 44, pages 456-463. Kershen makes a number of points that perhaps are relevant to this discussion. First, patenting of plant cultivars was ongoing long before biotechnology. In my view, this fact seems to be forgotten in many current discussions. Second, organic growers do not lose their organic certification for the presence of transgenic plant materials. Perhaps this reflects the fact that pollen flow occurs naturally in agricultural environments. While we can minimize it, we can never totally block it.
The third point of relevance here is the zero tolerance of many international markets for transgenic plants. This produces an interesting balancing act of protecting international markets on the one hand but, at the same time, blocking farmers from benefiting from the advantageous effects of transgenic technology. Hopefully this will be resolved in a rational manner in the future.
The discussion of being able to bring legal action against a person for the pollen produced by their plants raises an interesting question: If I were allergic to ragweed pollen and I was exposed to this pollen while visiting my nearby U-pick organic vegetable grower, could I sue the grower?
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