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Herbicide resistance may confer an advantage on plants in the wild.

Credit Xiao Yang
One of the most common methods that makes crops resistant to herbicides was found to be superior over rice varieties that are weedy. The results suggest that the effects of such modification could extend beyond farms and into the wild. Many varieties of crops are created genetically to be resistant to the glyphosate. ラウンドアップ The herbicide, first called Roundup, was introduced to the market in 1996 under the tradename Roundup. This allows farmers to eradicate weeds from their fields without harming their crops.

Glyphosate blocks an enzyme called EPSP synthase that is responsible for the production of specific amino acids and other molecules. It can also inhibit the growth of plants. ラウンドアップ The technique of genetic modification utilized, for instance, in the Roundup Ready crops made by the biotech giant Monsanto, based in St Louis, Missouri -generally involves inserting genes into a plant’s genome to increase EPSP-synthase’s production. The genes typically come from bacteria that have affected the plants.

The plant is able to resist the effects of glyphosate because of the addition of EPSP synthase. Biotechnology labs have tried using plant genes to boost EPSP synthase production. This was partly to make use of a loophole that is in US law that permits regulatory approval of transgenes contained in organisms that are not derived from bacteria pests.

A few studies have looked into the possibility that transgenes, such as glyphosate-resistant ones are able to — when introduced to wild or weedy plants through cross-pollination increase the competitiveness of these plants in survival, reproduction and growth. ラウンドアップ “The conventional belief is that any transgene will confer disadvantage in the wild in the absence of pressure to select, because the additional machinery could reduce the fitness,” says Norman Ellstrand an expert in plant genetics at the University of California in Riverside.

Lu Baorong from Fudan University in Shanghai is now challenging that view. The study shows that resistance to glyphosate even when not applied to a weedy variety of the rice crop can provide a significant health boost.

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

The group then let the offspring of crossbreeding to cross-breed with one other to produce second-generation hybrids. They were identical genetically with the exception of the amount of EPSP synthase genes they carried. The team found that those that had greater than one copy of the gene that codes for EPSP synthase expressed more enzyme and produced more tryptophan, as expected.

Researchers also discovered that the transgenic hybrids had higher rates of photosynthesis. They also they grew larger flowers and shoots and produced 48 to 125 percent more seeds than the non-transgenic hybridswithout the use of glyphosate.

Making weedy rice more competitive may exacerbate the problems it causes for farmers around the world where plots are ravaged by pests, Lu says.

Brian Ford Lloyd, a UK plant scientist, has said that the EPSP Synthase gene is able to get into wild rice species. This would threaten the genetic diversity of their species, which is very important. “This is an example of the extremely plausible detrimental effects [of GM plantson our environment.”

This study challenges public perception that genetically modified crops with additional copies of their own genes are more secure than those that contain genes from microorganisms. “Our study shows that this is not always the case,” Lu says. Lu.

According to some researchers this research suggests that the future regulation of genetically engineered crops needs to be rethought. ラウンドアップ Ellstrand claims that “some people now believe that biosafety regulations can be relaxed because we have the most comfort with genetic engineering over the last two decades.” “But the study proved that new products require careful analysis.”