affected farmers’ economic welfare so far, but research is needed on how market structure may affect ongoing access to non-GE or single-trait seeds and future seed prices. Furthermore, there has been comparatively little research on how changes in farmer social networks and seed-industry concentration might be affecting farmers’ planting decisions and options, overall yield benefits, crop genetic diversity, and economic returns.

A final set of social issues has to do with complex legal issues, including the adoption of and the use of genetic-engineering technology. U.S. and Canadian courts have upheld the legal rights of seed companies to prohibit seed-saving practices through the use of contracts. The issue of gene flow is complicated. One important question being raised is whether adventitious presence of genetic material from GE crops into non-GE crops impinges on the rights of producers, including organic producers, who do not wish to use specific GE traits. The legal debates may mask deeper social and ideological divisions over the use of GE plants and how to define and implement sustainable agricultural practices.

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