Genetically modified seeds, introduced in 1980, revolutionized farming, but their resistance to the commonly-used weed killer Round-Up may no longer be an advantage as Sandy Hausman reports.
Most corn and soy beans in this country are grown from seeds resistant to weed killers and bugs, but in 1996 Australian farmers reported weeds that were highly resistant to the herbicide Round-Up. Now, 20 years later, an economist at the University of Virginia says American farmers may also be finding that weeds can fight back.
“The adoption of these GMO seeds has decreased the use of insecticide," he says. " For herbicides what we have seen is there was a decrease in the use of chemicals, but over time it has been going up.”
Federico Ciliberto and two of his colleagues studied the chemicals used by 5,000 farmers and discovered they were using more herbicides – specifically, products other than Round-Up. Their findings are published in Science Advances.