Too Much Of A Good Thing: The Cautionary Tale of Biotech Crops

Resistance

The evolution of insect resistance to Bt crops has become a significant challenge for farmers. Dan Charles explains that genetic variations among insects, like cotton bollworms, have led to some developing resistance to Bt crops due to selection pressure 1. This resistance has emerged over time, with insects evolving to withstand different Bt genes, sometimes taking as long as 20 years 1.

It's evolution right in front of your eyes.

--- Dan Charles

The introduction of Bt crops initially reduced the need for insecticide sprays, benefiting both farmers and the environment. However, as resistance grows, farmers face the challenge of managing these resilient pests 2.

   

Advice

Scientific recommendations have been made to manage Bt crop resistance, but implementation has been inconsistent. Dan Charles notes that scientists have long advocated for planting non-Bt crops as refuges to slow resistance development, but these measures were not fully adopted 1. The Environmental Protection Agency's advisors suggest limiting the use of certain Bt genes to prevent overuse, but companies like Syngenta resist these changes 3.

If current farming practices don't change, it's possible that all of the BT genes that are currently on the market will stop working reliably within ten years.

--- Dan Charles

Without changes, farmers may need to revert to older pest control methods, such as crop rotation, to combat resistant insects effectively 3.