Tougher Weeds? Borrowed gene helps wild sunflower

Tests of sunflowers show for the first time that a gene from a genetically engineered crop gives a wild, weedy relative an edge in life outdoors, say researchers. That extra toughness feeds worries that genes escaping from transgenic crops could create feistier weeds.

Thanks to a gene borrowed from the Bacillus thuringiensis bacterium, the sunflower variety used in the test makes built-in Bt pesticide.