Tough times for corn

Wilting corn

[audio:http://wamcradio.org/EarthWise/wp-content/uploads/2012/09/EW-10-19-12-Ag-War.mp3|titles=EW 10-19-12 Ag War]

This year, drought dealt a heavy blow to U.S. corn production, with the U.S. Department of Agriculture listing half the crops in poor or very poor shape. Yields are down and corn prices are rising–bad news for food processors, dairy operations, and livestock farms. Further complicating things, low inland water levels are causing shipping headaches for the barges that haul the grain.

And if this was not enough, genetically-modified corn crops are losing their ability to repel root worms, a costly agricultural pest.

Over the past fifteen years there has been widespread adoption of what scientists call “Bt corn.” Plants are modified with genes from Bacillus thuringiensis, a soil bacterium that creates natural pesticides. This allows Bt corn to kill foraging pests, saving millions in crops damages.

But there has long been concern that continued Bt exposure could lead to disease resistant pests. This situation is magnified when farmers fail to plant ‘refuge fields’ nearby; these sites encourage surviving resistant insects to mate with partners that are not likely to be disease resistant.

Unfortunately, less than half of the Bt corn grown in the Midwest complies with EPA requirements for refuge fields.

So it was no surprise last year when University of Iowa researchers confirmed that rootworms collected from damaged Iowa crops had elevated Bt resistance.

The EPA is recommending that biotech companies adopt a remedial action plan to combat Bt insect resistance in the Corn Belt. Without proper management, our arms race with crop pests will only continue to escalate.