GM cotton genes found in wild species

Monday, 28 May 2012

GM crops

GM cotton genes found in wild species

María Elena Hurtado

13 October 2011 | EN | ES

Just under a quarter of the wild cotton seeds assessed contained transgenes from modified cotton

Flickr/João de Deus Medeiros

[SANTIAGO, CHILE] Genetically modified (GM) cotton genes have been found in wild populations for the first time, making it the third plant species — after Brassica and bentgrass — in which transgenes have established in the wild.

The discovery was made in Mexico by six Mexican researchers investigating the flow of genes to wild cotton populations of the species Gossypium hirsutum.

They found transgenes from cotton that had been modified to resist insects, herbicides or antibiotics in just under a quarter of the 270 wild cotton seeds assessed for that purpose. One of the contaminated seeds came from a wild plant located 755 kilometres away from the nearest GM cotton plantation. Others were beyond first-generation hybrids because they carried multiple and different transgenes.

According to the researchers, the GM seeds could have been dispersed by long distance lorry drivers transporting seeds for animal feed or oil extraction; by mild or strong winds; by fresh or salt water; or by birds and animals that had eaten them.

Norman Ellstrand, professor of genetics at the University of California, Riverside, United States, said this is the first study that finds transgenes in unmanaged cotton populations. He added that this is third system, after Brassica and bentgrass, in which transgenes have established in the wild

"It also highlights how seed dispersal has been an under-appreciated avenue of transgene movement," he said.

The flow of genes between cultivated GM or non-GM cotton plants and their wild relatives reduces the genetic diversity of cotton. This can have consequences for the environment, food safety and health, as well as legal and commercial implications.

"It is urgent to stop the flow of genes between cultivated and wild plants," Ana Wegier, lead author of the study and a researcher at the National Autonomous University of Mexico's ecology institute, told SciDev.Net.

"Post-harvest seeds must be destroyed and Mexico must have active monitoring, control and mitigation programmes," she said.

But Jonathan Wendel, an expert in the evolution of cotton and head of the Department of Ecology, Evolution, Biology and Organismal Biology at Iowa State University, United States, is cautious about the results of the study.

"The plants they identified may, for various reasons, be not truly wild but derived from cultivated plants. If this is the case, the long distance gene flow between transgene and wild populations reported may reflect human, not natural activity," Wendel told SciDev.Net.

More than 95 per cent of cultivated cotton worldwide was domesticated from G. hirsutum, which originated and diversified in Mexico. The first permits for planting GM cotton in Mexico were granted in 1996.

The study was published in the October edition of Molecular Ecology.

Link to abstract in Molecular Ecology

References

Molecular Ecology doi: 10.1111/j.1365-294X.2011.05258.x (2011)

Comments (5)

Nagib Nassar,Universidade Brasilia,Brasil ( Brazil )

17 October 2011

If this examined wild cotton is no more than (ESCAPEE) as J.Wenel tells, this may support claims that resistant to herbicide GM cotton varieties turn to be very dangerous weeds. They compete with weeds and grows wildly in distant and new habitats. Human has to control them before they devast all the area. A new beast now is born. See more in

http://www.the-scientist.com/news/20051130/01
and
http://www.geneconserve.pro.br/excerpts08.htm
and
http://www.geneconserve.pro.br/excerpts06.htm

Robert ( United States of America )

17 October 2011

"But Jonathan Wendel, an expert in the evolution of cotton and head of the Department of Ecology, Evolution, Biology and Organismal Biology at Iowa State University, United States, is cautious about the results of the study."

Of course! We should just throw caution to the wind and plant genetically-engineered versions of every crop completely willy-nilly because it won't hurt anything at all. Right.

Alison Tottenham ( www.tigergreen.co.uk | United Kingdom )

17 October 2011

GM genes in wild Cotton 755km away from the parental crop, is no surprise. After all, anyone who has studied, botany and a modicum of meterology (weather behaviour) realized long ago that this is exactly what will happen. Nagib Nassar is absolutely correct. Although most plants breed true for most of the time, this does not happen 100% of the time; and genes from one plant can jump species and with the help of thermals, birds and insects, these genes can travel long distances. Most worrying of all, a farmer buying land, will have no idea which pesticidal resistances have been bred into previous crops, and may therefore be present in his weeds! While this may not worry the big seed companies, it could bring a very heavy financial burden to the host of small farmers who produce most of the world's food.

RP ( New Zealand )

18 October 2011

Hi Alison, Once the herbicide resistant gene is in the wild population it is of no use to the plant as no one sprays herbicides in the wild. It may float around but will not be the beast Nagib is worried about. What is the importance of herbicide resistance for natural evolution of a plant population? However, each country/continent should regulate the characters introduced in crops so the gene flow does not make wild populations vulnerable, whether the characters are introduced through GM or other means.

J. Fulcher ( United Kingdom )

12 January 2012

Does RP underestimate the effect of the GM cotton? Surely it doesn't matter whether Mother Nature is interested or not, it's how the plant interacts with other cotton plants wherever it lands. If it does interact, as pointed out, there could be a mass of crossed plants not killed by herbicide and free to spread wherever. Mother Nature couldn't give a damn, they are all her 'children'. As someone who worked on pollen analysis for some years, the statements given out years ago about a 25 metre gap around the crops was 'quite sufficient ' to stop spread was both laughable and criminal, knowing that pollen grains are found in the upper atmosphere. J.Fulcher

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