Herbicide resistance might confer an advantage on plants in the wild.
Credit Xiao Yang
A common technique for genetic modification of crops that make them herbicide-resistant has been proven to provide advantages to the weedy varieties of rice even when herbicide isn’t in use. This finding suggests that these modifications may be detrimental to the natural environment beyond farms.
Many crops are created genetically to resist the glyphosate. ラウンドアップ , first known as Roundup and then introduced into the market in 1996 under the tradename Roundup. Farmers can eliminate the majority of weeds from their fields with this glyphosate resistance , without causing damage to their crops.
Glyphosate blocks an enzyme called EPSP synthase that is responsible for the production of certain amino acid and various other molecules. It can also hinder plant growth. The technique of genetic modification is employed in, for instance, Roundup Ready plants made by Monsanto Biotechnology Inc., a biotech firm based out of St Louis, Missouri. It involves inserting genes into the genome of a crop to increase EPSP synthase synthase synthase production. ラウンドアップ come from bacteria that infect plants.
The plant can withstand the effects caused by glyphosate because it has an additional EPSP-synthase. Biotechnology labs are also looking to use genes from plants rather than bacteria to increase EPSP synthase. This is due to the fact that the US law allows for regulatory approval to allow organisms with transgenes to be recognized as acceptable.
There aren’t many studies that have examined whether transgeneslike ones that confer resistance to glyphosate, can help plants to be more resilient in survival and reproduction once they cross-pollinate with wild or weedy species. Norman Ellstrand of University of California Riverside says, “The conventional expectation is that any transgene that is found in nature will confer disadvantage if there’s no selection pressure because the additional machinery may decrease the health.”
ラウンドアップ , an ecologist from Fudan University in Shanghai has changed the way that he views this. He found that resistance to glyphosate provides an impressive fitness boost to a weedy version of the popular rice crop Oryza Sativa.
ラウンドアップ and his coworkers genetically modified the cultivated Rice species to express its EPSP synthase. Then, ラウンドアップ crossed it with an weedy parent.
The group then allowed the offspring of cross-breeding to cross-breed to create second-generation hybrids. They were genetically identical except for the amount of EPSP synthase genes they had. As expected, the ones with more copies had higher enzyme levels and produced an increased amount of amino acid tryptophan compared to their counterparts that were not modified.
ラウンドアップ found that plants with transgenic genes were more photosynthesis-intensive, produced more flowers, and produced 48 to 125 percent fewer seeds per plant than nontransgenic hybrids. This was despite the fact that glyphosate was never present.
Making the weedy rice more competitive can exacerbate the problems it causes for farmers all over the world whose plots are invaded by the pest, Lu says.
Brian Ford-Lloyd (a UK plant geneticist) says that if the EPSP-synthase genes are introduced into wild rice species, then their genetic diversity, which is vital to preserve could be threatened. The transgene could outcompete normal species. “This is one of the most clear instances of the extremely damaging consequences [of GM crops] on the environment.”
Many people believe that genetically modified plants containing more than one copy of their genes than microorganisms are safe. This is not supported by this study. “Our study shows that this is not necessarily the case” says Lu.
The findings call for a rethinking of future regulations for the genetically altered crops, researchers say. Ellstrand believes that some believe biosafety regulations can be relaxed because we’ve had over two years of genetic engineering. https://www.komeri.com/disp/CKmSfGoodsPageMain_001.jsp?GOODS_NO=1013169 found that any new products should be carefully evaluated.