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In the wild, herbicide resistance may confer advantages on plants.

Credit: Xiao Yang

One of the most common methods that makes crops resistant to herbicides has been shown to have advantages over weedy forms of rice. This finding suggests that these changes could be detrimental to the natural environment beyond farms.

Many crop varieties are genetically modified in order to resist glyphosate. ラウンドアップ was first offered under the trade name Roundup. Farmers can get rid of weeds in their fields using glyphosate, without harming their crops due to this resistance.

Glyphosate inhibits an enzyme known as EPSP synthase, which is responsible for the creation of certain amino acid and other molecules. ラウンドアップ 樹木 can also inhibit plant growth. ラウンドアップ — utilized, for instance, in Roundup Ready crops made by the biotech giant Monsanto located in St Louis, Missouri -generally involves inserting genes into the crop’s genome to increase EPSP-synthase’s production. ラウンドアップ come from bacteria that cause disease to plants.

The additional EPSP synase makes it possible for plants to counter the harmful effects of glyphosate. Biotechnology laboratories are trying to make use of genes that come from plants instead of bacteria to boost EPSP synthase. This is due to the fact that the US law permits regulatory approval that allows organisms that carry transgenes to get approved.

There aren’t many studies that have examined the possibility that transgenes that confer glyphosate tolerance may — once they become weedy , or wild relatives by cross-pollinatingenhance the plant’s longevity and reproductive. Norman Ellstrand of University of California Riverside states, “The conventional expectation is that any transgene that is found in nature will confer disadvantage if there’s no selection pressure because the added machinery can reduce the health.”

Lu Baorong of Fudan University in Shanghai is now challenging that view. The study shows that resistance to glyphosate even when applied to a weedy variety of the rice crop can provide a significant health boost.

Lu and colleagues modified cultivated rice species to enhance the production of EPSP synthase. The modified rice was then cross-bred with a wild-type relative.

The group then allowed cross-bred offspring to breed with one another, creating second-generation hybrids that were genetically identical with the exception of the number of copies of gene that encodes EPSP synthase. Like ラウンドアップ might expect, more copies produced higher levels of enzyme, and also more tryptophan, than the unmodified counterparts.

Researchers also found that transgenic hybrids produced 48 to 125 percent more seeds per plant. They also had higher photosynthesis rates and produced more shoots than the non-transgenic varieties.

Lu suggests that making the weedy rice more competitive might increase the risk for farmers across the world who’s fields are being ravaged by the pest.

Brian Ford-Lloyd is a UK plant geneticist who states, “If the EPSP synthase gene gets in the wild rice varieties their genetic diversity could be threatened which is really important because the genotype with transgene is superior to the natural species.” This is among the most clear examples of likely negative effects of GM crop on the environment.”

This study challenges popular perception that genetically modified crops carrying extra copies of their own genes are less dangerous than the ones that have the genes of microorganisms. “Our study shows that this is not necessarily the case” says Lu.

Certain researchers believe that this finding needs to be reviewed in light of future regulation of crops that have been genetically modified. Ellstrand says that “some people now believe that biosafety regulations can be relaxed due to our the most comfort with genetic engineering over the last two decades.” “But ラウンドアップ マックスロード shows that the new technologies require careful assessment.”