In addition, the cumulative effects of additional transgenic protective traits on this weedy crop relative deserve further scrutiny, especially if the traits are linked and inherited as a unit. Protection from several common cucurbit viruses is expected to have a greater effect on weedy populations than resistance to only two or three.

In conclusion,

USDA's assessment about how the spread of virus-protective transgenes will affect free-living C. pepo populations is not well supported by scientific studies.

A precedent was set with the deregulation of Freedom II, which had protective traits similar to those of a conventionally bred variety. On the basis of its approval of Asgrow's CZW-3 squash, USDA seems unconcerned about incremental increases in the number of viral-protection traits that will be transferred to weedy wild relatives of squash. In cases like this, the committee recommends that

USDA should require original data to support agency decision-making concerning transgenic crops when published data are insufficient.

In cases when crucial scientific data are lacking about the potential impacts of gene flow on wild or weedy relatives, the committee recommends delaying approval of deregulation pending sufficient data (for example, surveys from several years over several regions), establishing a scientifically rigorous monitoring program in key areas to check for undesirable effects of resistance transgenes after the transgenic pest-protected plant is commercialized, or restricting the initial areas where the plants can be grown.

Restricting the areas where the squash can be initially grown would be preferable to unconditional deregulation, at least until more data are available.


Papaya (Carica papaya) is an important fruit crop in lowland regions of many subtropical and tropical countries, including Brazil, India, Mexico, Thailand, Vietnam, and Australia. It is a fast-growing, tree-like herbaceous plant that bears fruit in its first year and is usually replanted after 2 years, when the fruits are too high to harvest easily. In commercial plantations, papaya is often infected by the common, aphid-transmitted papaya ringspot virus (PRSV), which causes severe stunting and low fruit

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