From the Independent:
Previous studies into the economics of growing GM crops have concentrated on the farmers who have taken up the technology, but the latest research looked at a wider area, including non-GM fields that may have benefited from being near fields planted with GM varieties.GM maize, which is called corn in the US, has a bacterial gene called “Bt” added to it so that the plant excretes a protein which has a toxic effect on the European corn borer, a serious insect pest introduced accidentally into America in 1917.
Nearly two-thirds of the US corn belt is now cultivated with Bt maize, and it has had a dramatic impact on the decline of the corn borer moth, which cannot distinguish between the GM and conventional varieties. When female moths lay their eggs on Bt corn, the larvae die within two days of hatching.
Paul Mitchell, an agricultural economist at the University of Wisconsin-Madison where the work was carried out, said the main corn-growing states of Wisconsin, Minnesota, Illinois, Iowa and Nebraska experienced a total economic benefit of $6.9bn (£4.6bn) over the period from 1996 to 2009 as a result of less maize being lost to the corn-borer pest.
But the non-GM corn areas accounted for 62 per cent of this total economic benefit because, in addition to preventing crop losses resulting from lower levels of pests, these farmers did not have to spend any extra money on the technology fees associated with the purchase of GM maize.
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