Rootworms Show Resistance To Bt Corn

From Bloomberg, via nc links:

Monsanto Co. (MON) corn that’s genetically engineered to kill insects may be losing its effectiveness against rootworms in four states, the U.S. Environmental Protection Agency said.
Rootworms in Iowa, Illinois, Minnesota and Nebraska are suspected of developing tolerance to the plants’ insecticide, based on documented cases of severe crop damage and reports from entomologists, the EPA said in a memo dated Nov. 22 and posted Nov. 30 on a government website. Monsanto’s program for monitoring suspected cases of resistance is “inadequate,” the EPA said.
“Resistance is suspected in at least some portions of four states in which ‘unexpected damage’ reports originated,” the EPA said in the memo, which reviewed damage reports.
The insects, which begin life as root-chewing grubs before developing into adult beetles, are among the most destructive corn pests, costing U.S. farmers about $1 billion a year in damages and chemical pesticides, according to the U.S. Department of Agriculture.

And this:

The agency said in the memo that SmartStax could lose its effectiveness if it’s planted in fields where bugs have developed a tolerance to Monsanto’s Bt gene, known as CRY3bB1. That’s because SmartStax’s effectiveness is predicated on both types of Bt working as designed. SmartStax corn produces the second type of Bt, called Cry34/35, with a gene licensed from Dow Chemical Co. (DOW)
To deter resistance to all types of Bt corn, the EPA requires farmers who use the modified crop to also plant corn that doesn’t produce the pesticide. The agency reasons that bugs in the so-called refuge that are not exposed to the toxin will mate with any resistant rootworms, creating a new generation of insects that are once again susceptible to the insecticide.
Some corn farmers don’t appear to be planting the required refuges in Minnesota, where moderate to severe rootworm damage is spreading and occurred for a third straight year in 2011, according to the EPA.

This is bad news for everyone involved.  Here in western Ohio, where corn-soybean rotations are almost always employed, I haven't heard of much rootworm damage.  But that may soon change, and would bring some very nasty insecticides back into wide use.