|
Bt GM (genetically modified)
crops
Since
1996 plants have been modified with short sequences of genes from Bt
to express the crystal protein Bt makes. With this method, plants
themselves can produce the proteins and protect themselves from insects
without any external Bt and/or synthetic pesticide sprays. In
1999, 29 million acres of Bt corn, potato and cotton were grown
globally. It has been estimated that by using Bt protected cotton,
the United States was able to save approximately $92 million.
Bt GM crops are protected specifically against
European corn borer, southwestern corn borer, tobacco budworm, cotton
bollworm, pink bollworm and the Colorado potato beetle. Other benefits
attributed to using Bt include:
- Increased opportunity for beneficial insects – Bt proteins
will not kill beneficial insects.
- Reduced pesticide exposure to farm workers and non-target organisms.
Potential risks to using Bt:
-
Invasiveness – Genetic modifications, through
traditional breeding or by genetic engineering can potentially change
the organism to become invasive. Few introduced organisms become invasive,
yet it’s a concern for the users.
-
Resistance to
Bt - The biggest potential risk to using Bt-crops
is resistance. Farmers have taken many steps to help prevent resistance.
|