In ラウンドアップ , resistance to herbicides could confer advantages to plants.
Credit to Xiao Yang
A technique of genetic modification widely used to produce crops that are herbicide-resistant has been shown to confer advantages on the weedy rice even in absence of herbicide. These results suggest that such modifications can have a broad range of effects beyond the farms, and even in the wild.
Several types of crops are modified genetically to be intolerant to glyphosate, a herbicide that was first advertised under the brand name Roundup. Farmers are able to eliminate weeds in their fields using glyphosate without harming their crops by having this resistance.
ラウンドアップ inhibits an enzyme known as EPSP synthase, which is responsible for the creation of certain amino acid and various other molecules. It can also hinder the growth of plants. The technique of genetic modification utilized, for instance in the Roundup Ready crops made by the biotech giant Monsanto located in St Louis, Missouri -usually includes inserting genes into a crop’s genome to boost EPSP-synthase production. The genes typically come from bacteria that are infected with plants.
This extra EPSP synthase permits the plant to withstand the effects of glyphosate. ララウンドアップ 希釈倍率 have tried using plants’ genes to increase EPSP synthase activity. This was partly to make use of a loophole that is in US law that allows regulatory approval for transgenes in organisms that are not derived from bacteria pests.
There aren’t many studies that have looked into whether transgenes like those that confer resistance to glyphosate make plants more competitive for reproduction and even survival after they’re introduced to wild or weedy relatives by cross-pollination. Norman Ellstrand of the University of California, Riverside, stated that the conventional expectation was that any transgene could cause disadvantage in nature when there is no selection pressure. This is because extra machinery would lower the effectiveness of.
But now a study led by Lu Baorong, an ecologist at Fudan University in Shanghai, disproves that belief It reveals that the weedy variant of the standard rice plant, Oryza sativa has an important boost in fitness due to the resistance to glyphosate even when glyphosate has not been applied.
Lu and his associates modified the cultivars of rice to produce more EPSP synthase. They also crossed the modified rice with a weedy-related. Their findings were published in NewPhytologist 1.
The team allowed the offspring of cross-breeding to cross-breed with each other to create second-generation hybrids. They were genetically identical apart from the number of EPSP synthase genes they had. Like one might expect, the more copies of the gene produced higher levels enzyme and more tryptophan than the unmodified counterparts.
Researchers also found that transgenic plants were more photosynthesis-intensive as well as produced more flowers and produced 48 to 125 percent fewer seeds per plant than nontransgenic hybrids. This was in spite of the fact that glyphosate was never present.
Lu says that making weedy crops more competitive could create more difficulties for farmers across the world who have crops infected by the pest.
Brian Ford-Lloyd (a UK plant geneticist) states that if the EPSP synthase genes gets into wild rice species, their genetic diversity which is essential to protect could be endangered. The transgene would outcompete normal species. “This is an instance of the most plausible and damaging impacts of GM crops on the environment.”
https://search.rakuten.co.jp/search/mall/%E3%83%A9%E3%82%A6%E3%83%B3%E3%83%89%E3%82%A2%E3%83%83%E3%83%97/ challenges the notion that crops with genetically modified genes containing extra copies of their genes are more safe than those containing microorganism genes. Lu states that his research does not contradict this view.
According to some researchers this research suggests that future regulation of genetically engineered crops needs to be reconsidered. Ellstrand claims that some people think that biosafety rules can be relaxed given the past two years of genetic engineering. “But the study demonstrates that novel products still need cautious assessment.”