Genetically modified crops are planted throughout the Midwest, but some scientists are concerned genes from these crops could escape and work their way into weedy plants. With these genes, weeds could become more vigorous and harder to kill. New research shows this can happen between closely related crops and weeds. The Great Lakes Radio Consortium’s Cristina Rumbaitis-del Rio prepared this report:
Genetically modified crops are planted throughout the Midwest, but some scientists are
concerned genes from these crops could escape and work their way into weedy plants. With
these genes, weeds could become more vigorous and harder to kill. New research shows this can
happen between closely related crops and weeds. The Great Lakes Radio Consortium’s Cristina
Rumbaitis-del Rio prepared this report:
Genetically modified crops have been around for quite a while. In the U.S. last year more than 88
million acres were planted with genetically modified soybean, corn, cotton and other crops. Some
of these plants are engineered to be more resistant to herbicides, making it easier for farmers to
get rid of weeds without damaging their crop. Others are engineered to resist plant-eating insects.
But some scientists worry about the ecological effects of these crops. Allison Snow is a professor
of ecology at Ohio State University. She studies genetically modified sunflowers. Snow says she
got involved in this research when genetically modified crops were first being introduced because
she was afraid no one else was looking at the environmental effects of these crops.
“It was kind out of a fear factor for me of wanting to make sure that someone was watching to see
what the environmental effects might be.”
The sunflowers Snow studies have a gene added to them, which produces an organic insecticide
that kills insects feeding on the plants.
According to Snow, the problem with these pesticide-producing sunflowers is the insect-killing
gene can be transferred from crop sunflowers to their weedy cousins, which are often growing on
the edges of fields. Bees, flies and other insects can transfer the gene to the weeds by cross-
pollinating the plants, which are close relatives. Snow’s research shows once the gene gets into
the weed population, the weeds become insect-resistant as well.
“The new gene worked really, really well in the weeds. It protected them from the insects. And
because they were protected, they had more energy to devote to making seeds.”
Snow says the most startling result was the number of seeds these weeds were making.
“In one of our study sites, they made 55% percent more seeds per plant – just because of one
gene. Which is kind of unheard of. We’ve never seen a result like that – where one gene would
cause the whole population to suddenly start making 55% more seeds.”
The gene might make weeding a more difficult task, but Snow says she wouldn’t quite call them
“super weeds,” a term some environmentalists have used.
“We might see that the weedy sunflowers become worse weeds, I wouldn’t call them super
weeds, because to me that would imply that they have many different features instead of just one
that causes them to make more seeds. But I could imagine in the future there might be enough
traits out there that could turn a regular weed into something much more difficult to control – like
really would be a super weed.”
Snow says she will have to do more research to see if the extra seeds made by the weeds will turn
into more weeds and hardier weeds in farmer’s fields.
But, she might not be able to finish her research on sunflowers because the companies that make
the crop have decided not to renew her funding and won’t give her access to the sunflowers or the
“It was all about stewardship and responsibility.”
Doyle Karr is a spokesperson for pioneer hi bred, one of the companies which makes the
sunflowers. He says the company realized a few years ago there wasn’t enough demand for the
product to justify commercially producing it. As a result, he says, the company couldn’t continue
funding sunflower research, and doesn’t want to be held responsible for keeping the gene safe
while the research is being conducted.
It’s an issue of a biotech trait that we are not pursuing and not bringing to the market, and if we’re
not bringing it to the market, we can’t justify taking the responsibility of having that trait out
being worked with, with a third party.”
While some academic researchers argue the universities take on legal liability when they work
with genetically modified plants, Karr says the university’s liability is often limited by state law.
He says the company is ultimately held responsible if only by the court of public opinion.
“Should something happen with this gene that was not expected or a mistake happened – that
would ultimately come back to those who initially made the gene available.”
While this issue remains unresolved, Snow is continuing her research. Genetically modified
sunflowers are not the only crop to study. Snow is now working in Vietnam where weedy species
of rice grow naturally, and where genetically modified rice might be introduced in coming years.
She’s concerned the traits of the genetically altered rice might be transferred to the wild species
of rice, just as happened with the sunflowers.
For the Great Lakes Radio Consortium, I’m Cristina Rumbaitis-del Rio.