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SAMPLE PETITIONHerbicide-Tolerant Plants

D. Appearance of Glyphosate-Resistant Weeds

A decade ago, herbicide-resistant weeds were virtually unknown. Today there are some 109 herbicide-resistant weed biotypes and more than half of them are resistant to triazine (LeBaron, 1991). Certain herbicide characteristics and application regimes favor the development of resist- ant weeds: a single target site and a specific mode of action, broad spectrum of activity, long residual activity the capacity to control weeds through out the year, and frequent applications without rotation to other herbicides or cultural control practices. Current application data sug- gest that glyphosate is unlikely to engender the develop- ment of resistance in target vegetation (Benbrook 1991).

E. Weediness of Banjaran

Will the introduction of the herbicide-tolerance genes to a plant increase its weediness? Exactly which characters define a weed is debatable, but a general consensus of the traits shared by many weeds was developed by Baker (1974). They include (1) the ability to germinate in many different environments; (2) discontinuous germination and great longevity of seed; (3) rapid growth through vegeta- tive phase to flowering; (4) continuous seed production for as long as growing conditions permit; (5) self- compatibility but partially autogamous and apometic;

(6) ability to be cross-pollinated by unspecialized visitors or wind-pollinated; (7) high seed output in favorable environments and some seed production in a wide range of environments; (8) adaption for short and long-distance dispersal; (9) vegetative production or regeneration from fragments and brittleness (hard to remove from the ground); and (10) ability to compete interspecifically by special means (e.g., rosette formation and presence of allelochemicals). Weeds need not have all these charac- teristics to be successful. G. hirsutum cv. Stoneville 825 that was genetically transformed is not considered a weed and has few of the 10 weedy traits. Introduction of the herbicide tolerance gene into this cultivar did not signifi- cantly change its weedy characteristics. No change was noted with transformed cultivar in the number of seeds


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