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In the wild, resistance to herbicides may confer advantages on plants.

Credit: Xiao Yang
It has been established that a technique for genetic modification, which is widely used to make crops herbicide-resistant, confers advantages on a weedy variety of rice. This suggests that these modifications may affect the environment beyond farms.

Many cultivars have been genetically modified so that they can ward off the effects of glyphosate. ラウンドアップ ラウンドアップ This herbicide was first offered under the trade name Roundup. Farmers can eliminate the majority of the weeds that grow in their fields by using this glyphosate-resistant crop without causing damage to their crops.

ラウンドアップ Glyphosate inhibits an enzyme known as EPSP synthase which is responsible for the creation of specific amino acids and various other molecules. It also can hinder the growth of plants. The technique of genetic modification that is employed by Monsanto’s Roundup Ready crops, which are located in St Louis (Missouri), typically involves inserting genes into a crop’s DNA to increase EPSP synthase production. ラウンドアップ The genes are usually derived from bacteria that cause disease in plants.

This additional EPSP synthase allows plants to resist the effects from glyphosate. Biotechnology labs have also attempted to make use of the genes of plants to increase the EPSP synthase enzyme, in part to exploit an American loophole which permits the approval of regulatory authorities of transgenes which are not derived from by bacterial pests.

There aren’t many studies that have examined whether transgenes such as those that confer resistance to glyphosate can — once they get into weedy or wild relatives through cross-pollination -make plants more competitive in survival and reproduction. ラウンドアップ Norman Ellstrand of the University of California, Riverside, stated that the conventional expectation was that any transgene will be detrimental to nature if there was no pressure to select. This is because extra machinery could reduce the effectiveness of.

Lu Baorong, an ecologist from Fudan University in Shanghai has changed the way that he views this. He discovered that resistance to glyphosate provides an impressive fitness boost to the weedy variant of the standard rice plant Oryza Sativa.

Lu and colleagues altered cultivars of rice to increase the production of EPSP synthase. The modified rice was then cross-bred with a wild relative.

The team then allowed offspring to crossbreed with one another, resulting in second generation hybrids which are genetically similar to their parents, except for the number of copies of the gene that encodes EPSP synthase. As expected, the hybrids that had more copies of the gene had a higher chance to make more tryptophan as well as have higher enzyme levels than the unmodified hybrids.

Researchers also found that transgenics had higher rates, had more flowers and 48 to 125 percent more seeds per plant than nontransgenics.

Lu believes that making rice that is weedy less competitive might make it more difficult for farmers who have their land infested by pests.

“If the EPSP-synthase gene gets into the wild rice plant, their genetic diversity, which is really important to conserve, could be threatened because the transgene’s genetic make-up would outcompete the normal species,” Brian Ford-Lloyd who is a plant geneticist at the University of Birmingham, UK. “This is one the most evident examples of highly plausible harmful impacts of GM crops] on the environment.”

The general public believes that genetically engineered crops with more copies or microorganisms’ genes are less risky than those containing only the genes of their owners. Lu declares, “Our study shows this is not necessarily true.”

Some researchers believe this finding needs to be reviewed in light of future regulation of genetically modified crops. Ellstrand claims that some people believe biosafety regulations can be relaxed given the past over two years of genetic engineering. The study showed that new products need to be carefully evaluated.