In the wild, herbicide resistance might confer an advantage to plants.
Credit Xiao Yang
A common method of genetic modification that makes crops resistant to herbicides was shown to be superior over the weedy varieties of rice. The findings suggest that this modification may be able to be beneficial to wild rice varieties and crop varieties.
https://search.kakaku.com/%8F%9C%91%90%8D%DC%20%83%89%83E%83%93%83h%83A%83b%83v%83%7D%83b%83N%83X%83%8D%81%5B%83h/ Many cultivars have been genetically modified so that they can resist the glyphosate. The herbicide was initially offered under the trade name Roundup. This resistance to glyphosate permits farmers to eliminate plants without doing any harm to their crops.
Glyphosate inhibits growth of plants by blocking EPSP synthase (an enzyme that plays a role in the creation of certain amino acids as well as various other molecules). https://search.rakuten.co.jp/search/mall/ラウンドアップ+マックスロード/ The enzyme can make up as much as 35 percent or more of the plant’s total mass. 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 The genetic-modification method, employed for Roundup Ready crops by Monsanto (based in St Louis in Missouri) is the process of inserting genes into the crop to increase EPSP-synthase output. Genes are typically derived usually from bacteria that cause disease to plants.
The plant is able to resist the effects of glyphosate because of the addition of EPSP synthase. Biotechnology labs are also trying to make use of genes that come from plants instead of bacteria to boost EPSP synthase. This is mainly due to the US law permits regulatory approval that allows organisms that carry transgenes to get recognized as acceptable.
A few studies have looked into the possibility that transgenes that confer glyphosate tolerance may — once they become weedy , or wild relatives via cross-pollinating -enhance the plant’s longevity and reproductive. Norman Ellstrand of the University of California, Riverside, said that the traditional expectation was that any transgene would confer disadvantage in nature if there is no selection pressure. This is because extra machines would reduce the fitness.
Lu Baorong (an ecologist at Fudan University, Shanghai) has now questioned that opinion. It shows that resistance to glyphosate can provide a significant fitness boost to the weedy rice crop called Oryza sativa even when not used.
Lu and colleagues altered cultivars of rice to increase the production of EPSP synthase. https://www.zennoh.or.jp/tc/einou/pesticides/ulv5/ The modified rice was then cross-bred with a wild-type relative.
ラウンドアップ The team then allowed the offspring of cross-breeding to be bred with each other to produce second-generation hybrids. These were genetically identical, with the exception of the number and copy count of the EPSP synthase gene. The ones with more copies expressed higher amounts of the enzyme and produced more amino acid tryptophan than the unmodified ones.
Researchers also found that transgenics have higher rates, had more flowers and 48-125% more seeds/plant than nontransgenics.
Lu claims that making the weedy grain more competitive can cause more problems to farmers all over the world whose crops are infected by the pest.
“If the EPSP-synthase gene gets into the wild rice plant, their genetic diversity, which is important to conserve may be at risk as the genotype with the transgene would outcompete the normal species,” says Brian Ford-Lloyd an expert in plant genetics at the University of Birmingham, UK. “This is among the most clear instances of the extremely damaging effects of GM crops] on the environment.”
The belief of the public that genetically modified crops with additional copies their genes are safe is disproved by this research. Lu states that the study “shows that this isn’t always the case”.
The finding calls for a review of future regulation of the genetically altered crops, scientists claim. Ellstrand states that “some people believe that biosafety regulations can be relaxed since we have a a high degree of comfort with genetic engineering over the last two decades.” “But the study demonstrates that new products require cautious examination.”