Insect Resistance to Bt Crops: Lessons from the First Seven Years
نویسندگان
چکیده
Large scale planting of Bt crops began in 1996 and grew quickly to more than 10 million ha per year. The cumulative area of Bt crops grown globally from 1996 to 2002 exceeded 62 million ha, enough to cover the states of California and Iowa. More than 99% of this area was planted with either Bt corn or Bt cotton producing Bt toxins Cry1Ab or Cry1Ac to kill larvae of lepidopteran pests. These Bt crops expose pests to Bt toxin throughout the growing season.
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