Herbicide resistance could confer an advantage on plants in the wild.
Weedy rice may absorb transgenes derived from genetically modified crops by cross-pollinating. Credit: Xiao Yang
A common method of genetic modification used to make crops more resistant to herbicides was shown to be superior over weedy forms of rice. This finding suggests that the modifications could have an impact on the environment beyond farms.
A variety of crop varieties have been modified genetically to make them immune to Roundup herbicide glyphosate. This glyphosate resistance enables farmers to eradicate the majority of weeds from the fields without causing damage to their crop.
Glyphosate may hinder the growth of plants by blocking EPSP synase which is an enzyme involved in the production of amino acids, as well as other chemical compounds that comprise about 35% of plant mass. Genetic modification, such as the Roundup Ready crops manufactured by Monsanto in St. Louis, Missouri, involves inserting genes into the genetic code in order to increase EPSP production. The genes are often derived from bacteria that have caused the infection of plants.
This additional EPSP synthase permits plants to counteract the effects of glyphosate. ラウンドアップ Biotechnology labs also have tried to create EPSP synthase with more plant-based components than bacteria using genes taken from plants. https://search.rakuten.co.jp/search/mall/ラウンドアップ+マックスロード/ This was partially done to exploit the loophole in US law that allows regulatory approval for species which aren’t the result of bacteria.
Few studies have examined whether transgenes like those that confer resistance to glyphosate make plants more competitive in reproductive success and longevity once they are introduced to wild or weedy relatives by cross-pollination. ラウンドアップ Norman Ellstrand of the University of California, Riverside, stated that the conventional expectation was that any transgene would be detrimental to nature if there is no selection pressure. This is due to the fact that any additional machinery would lower the performance of the.
ラウンドアップ Lu Baorong of Fudan University in Shanghai is now challenging that view. The study demonstrates that glyphosate resistance even when applied to a weedy variety of the rice crop can give a significant health boost.
Lu and his associates modified cultivars of rice to make more EPSP synthase. They also crossed the modified rice with a weedy-related. Their findings were published in NewPhytologist 1.
The researchers then allowed the hybrid offspring of crossbreds to reproduce with one another, resulting in second-generation hybrids genetically identical except in the number of copies of the gene that encodes EPSP synthase. Like one might expect, more copies produced higher levels of enzyme, and also more tryptophan, than their unmodified counterparts.
Researchers also found that transgenic hybrids are more photogenic, produced more plants per plant and had 48-125% higher yields of seeds than non-transgenic varieties.
Making the weedy rice more competitive may increase the issues it creates for farmers around the world whose plots are invaded by the pest, Lu says.
Brian Ford Lloyd, a UK plant scientist, has said that the EPSP Synthase gene may be introduced into wild rice species. This would erode their genetic diversity, which is extremely important. This is among the most clear examples of plausible negative effects [of GM crop] on the environment.”
https://www.komeri.com/search/%E3%83%A9%E3%82%A6%E3%83%B3%E3%83%89%E3%82%A2%E3%83%83%E3%83%97/?dispNo=&codeSearch=0&searchFirst=1 The public belief that genetically-modified crops with additional copies their genes are more secure is questioned by this study. Lu states that his study does not support this view.
According to some researchers this finding suggests that any future regulation for genetically engineered plants should be reconsidered. Ellstrand believes that some believe biosafety regulations can be relaxed because we’ve had two years of genetic engineering. “But the study demonstrates that the new technologies require careful evaluation.”