The wild plants could have an herbicide resistance advantage.
Credit: Xiao Yang
It has been proven that a genetic modification technique that is used extensively to create crops that are herbicide-resistant confers advantages on a weedy variety of rice. https://www.komeri.com/disp/CKmSfGoodsPageMain_001.jsp?GOODS_NO=1713321 suggests that these modifications may affect the environment beyond farms.
A range of crop varieties have been modified genetically so that they are immune to Roundup herbicide glyphosate. This glyphosate resistance enables farmers to wipe out most weeds from the fields without damaging their crop.
Glyphosate blocks the enzyme EPSP synthase which is responsible for the production of certain amino acid and other molecules. It can also inhibit the growth of plants. The genetic modification method used in Roundup Ready crops by Monsanto (based in St Louis in Missouri) involves inserting genetic material into a crop to increase EPSP synthase’s output. Genes are typically derived usually from bacteria that cause disease to plants.
The plant is able to resist the adverse effects of glyphosate due to its additional EPSP-synthase. Biotechnology labs are also trying to make use of genes from plants instead of bacteria to increase EPSP synthase. This is mainly due to the US law allows regulatory approval that allows organisms that have transgenes to be recognized as acceptable.
A few studies have looked into whether transgenes , such as those that confer resistance to glyphosate are able to — once they are wild or weedy relatives via cross-pollination -make plants more competitive for survival and reproduction. Norman Ellstrand of University of California Riverside states, “The conventional expectation is that any transgene found in the wild could confer disadvantage if there’s no selection pressure because the extra machinery could lower the fitness.”
Lu Baorong from Fudan University in Shanghai is in the process of challenging this notion. The study demonstrates that glyphosate resistance even when applied to the weedy type of rice crop can give a significant health boost.
In the study which was published this month in New Phytologist 1, Lu and his colleagues modified the genetics of the rice cultivar to enhance the species’ own EPSP synthase. They also crossed-bred the modified rice with a weedy cousin.
ラウンドアップ allowed the offspring of crossbreeding to crossbreed with each other, resulting in second-generation hybrids that are genetically identical with each other , with the exception of the amount of copies of the gene encodes EPSP synase. Like 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 might expect, more copies resulted in higher levels of enzyme as well as more tryptophan than their counterparts that were not modified.
https://www.jacom.or.jp/nouyaku/news/2019/10/191024-39457.php found that transgenic hybrids grew between 48-125percent more seeds per plant, and had more photosynthesis, and had more shoots than non-transgenic ones.
Lu believes that making weedy invasive rice more competitive may make it more difficult for farmers to repair the damage caused by this insect.
Brian Ford-Lloyd (a UK plant geneticist) states that if the EPSP synthase gene is introduced into wild rice, then their genetic diversity, which is essential to protect could be at risk. The transgene would outcompete natural species. “This is a prime example of the most plausible and damaging effects of GM crops on the environment.”
This study challenges belief that crops modified genetically carrying additional copies of their genes are less dangerous than those that contain genes from microorganisms. “Our study suggests that this isn’t necessarily the case” says Lu.
ラウンドアップ believe this discovery calls for a review of future regulation of crops that have been genetically modified. Ellstrand believes that biosafety regulations may be relaxed because we benefit from a high degree of comfort from two decades worth of genetic engineering. The study revealed that the newest products need to be carefully evaluated.