“Bt cotton” is genetically modified to produce a toxin from the bacteria Bacillus thuringiensis (Bt) that is deadly to the bollworm. More than 4 million hectares of Bt cotton are now grown in China.
But according to Nature:
“Numbers of mirid bugs (insects of the Miridae family), previously only minor pests in northern China, have increased 12-fold since 1997.”
Mirids are now the main pest in the region, and their rise in number can be directly linked to the scale of Bt cotton cultivation.Meanwhile, in the United States, farmers’ widespread use of Roundup weedkiller is spurring the creation of superweeds. There are now at least 10 different species of superweeds resistant to Roundup, spread over 22 states and millions of crop acres.
Sources:NYTimes.com May 4, 2010
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