The Growing Roundup-Resistant Weed Problem

THIRD WORLD NETWORK BIOSAFETY INFORMATION SERVICE

Dear Friends and colleagues,

RE: Growing Roundup-Resistant Weed Problem

The adoption of crops that are genetically engineered to tolerate the herbicide Roundup has resulted in a growing number of weed species that are resistant to glyphosate, the active ingredient in Roundup, due to widespread use of the herbicide. This has also led to a decline in the effectiveness of glyphosate as a weed-management tool.

According to weed expert David Mortensen, during the period since the introduction of glyphosate-tolerant crops, the number of weedy plant species that have evolved resistance to glyphosate has increased dramatically, from zero in 1995 to 19 in June of 2010. Based on the most recent data, glyphosate-tolerant weeds were reported on 30,000 sites and affected up to 11.4 million acres, up from 3,251 sites covering about 2.4 million acres in 2007.

The cost of forestalling and controlling herbicide-tolerant weeds is estimated to cost farmers almost $1 billion each year, at an additional cost of $10-20 per acre.

The trend is set to continue and the problem of resistance may worsen if multiple herbicide-tolerant crops are introduced, as increased use of herbicides is expected.

With best wishes,

Third World Network
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Growing Roundup-resistant weed problem must be dealt with, expert says Physorg.com
September 14, 2010
http://www.physorg.com/news203697204.html

Penn State weed scientist David Mortensen.

(PhysOrg.com) -- When Penn State weed scientist David Mortensen told members of the U.S. House Oversight Committee this summer that the government should restrict the use of herbicide-tolerant crops and impose a tax on biotech seeds to fund research and educational programs for farmers, it caused quite a stir.