Herbicide resistance may confer an advantage on plants in the wild.
Credit: Xiao Yang
It has been demonstrated that a technique for genetic modification is extensively used to make crops herbicide-resistant, gives advantages to the rice that is weedy. https://auctions.yahoo.co.jp/search/search?rkf=2&p=%E3%83%A9%E3%82%A6%E3%83%B3%E3%83%89%E3%82%A2%E3%83%83%E3%83%97&aucmaxprice=999999999&thumb=1&s1=score2&o1=a&isdd=1&ei=utf-8&fixed=3&nockie=1&isnext=1&ex_cat=2084006160,2084008038,2084034075&rewrite_ok_wand_re_search=1 suggest that the benefits of such modification have the potential to extend beyond farms and into the wild.
Many crop varieties are genetically altered so that they can resist the glyphosate. ラウンドアップ was initially sold under the tradename Roundup. Farmers can eradicate most the weeds that grow in their fields by using this glyphosate-resistant crop without damaging their crops.
Glyphosate inhibits growth of plants by inhibiting EPSP synthase (an enzyme that plays a role in the production of specific amino acids as well as other molecules). The enzyme can make up as much as 35 percent or more of a plant’s total mass. The technique of genetic modification employed, for example in the Roundup Ready crops made by the biotechnology giant Monsanto, based in St Louis, Missouri -usually involves inserting genes into the crop’s genome to boost EPSP-synthase production. Genes are typically obtained from bacteria that infects crops.
The plant can withstand the effects of glyphosate because of the extra EPSP synthase. Biotechnology labs have also tried to make use of genes from plants instead of bacteria to boost EPSP-synthase production partly to make use of a loophole that is in US law that allows the approval of regulatory agencies for organisms that carry transgenes that are not derived from bacterial pests.
A few studies have explored whether transgenes like those that confer glyphosate resistant can help plants compete for reproduction and even survival after they’re introduced to weedy or wild relatives by cross-pollination. Norman Ellstrand is a University of California Riverside plant geneticist. “The hypothesis is that any transgene will cause disadvantage in the wild, in absence of pressure to select, because it would reduce fitness,” Ellstrand said.
Lu Baorong is an Ecologist in Fudan University Shanghai. ラウンドアップ shows that resistance to glyphosate provides a significant fitness benefit, even though it isn’t applied.
In the study published this month in New Phytologist 1, Lu and his colleagues genetically modified the cultivated rice species to enhance its own EPSP synthase and cross-bred the altered rice with a weedy relative.
The group then permitted cross-breeding offspring to be bred with each other to produce second-generation hybrids. These were genetically identical except for the number and count of EPSP synthase gene. The ones with more copies expressed greater levels of the enzyme and also produced more amino acids tryptophan than the unmodified ones.
Researchers also discovered that transgenic hybrids have higher rates of photosynthesis, grew more shoots and flowers and produced 48-125% more seeds than the non-transgenic hybridswithout the use of the chemical glyphosate.
ラウンドアップ believes that making weedy rice less competitive could make it more difficult for farmers who have their plots affected by the pest.
Brian Ford Lloyd, a UK plant scientist, stated that the EPSP Synthase gene could get in wild rice varieties. This would erode their genetic diversity, which is important. “This is among the most clear instances of the extremely damaging impacts [of GM crops] on the environment.”
The study also challenges the perception that genetically modified crops that carry additional copies of their own genes are safer than those containing genes from microorganisms. “Our study suggests that this isn’t necessarily the case” Lu says. Lu.
Researchers say this finding calls for review of the regulations for the future on genetically modified crops. Ellstrand claims that “some people are now of the opinion that biosafety regulations could be relaxed since we have a a high degree of comfort with genetic engineering over the last two decades.” The study revealed that the newest products must be carefully evaluated.