Genetically modified plants are more beneficial than weeds
Herbicide resistance might provide advantages to plants in the wild.
ラウンドアップ of genetic modification widely used to make crops herbicide resistant has been found to provide advantages to an invasive form of rice, even in absence of herbicide. This suggests that these changes could have an impact on the environment beyond farm.
ラウンドアップ of crops are genetically modified to be intolerant to glyphosate, an herbicide first sold under the trade name Roundup. This resistance to glyphosate permits farmers to eliminate plants without doing any harm to their crop.
Glyphosate blocks an enzyme called EPSP synthase which is responsible for the creation of specific amino acids as well as other molecules. It can also hinder plant growth. Genetic modification, like the Roundup Ready crops manufactured by Monsanto in St. Louis, Missouri, involves inserting genes to a crop's genetic code in order to increase EPSP production. Genes usually come from bacteria that infect plants.
The added EPSP synthase helps the plant withstand the effects of glyphosate. Biotechnology labs also have tried to utilize genes from plants instead of bacteria to boost the production of EPSP synthase partly to make use of a loophole in US law that permits the approval of regulatory agencies for organisms that carry transgenes not derived from bacterial pests.
Few studies have looked into the possibility that transgenes, like ones that confer resistance to glyphosate, could help plants to be more resilient to surviving and reproduce once they cross-pollinate with weedy or wild species. Norman Ellstrand of the University of California, Riverside, explained that the standard assumption was that any transgene will confer disadvantage in nature if there was no pressure to select. ラウンドアップ is due to the fact that any additional machinery would lower the fitness.
Lu Baorong, an ecologist from Fudan University in Shanghai has revised that opinion. He has discovered that glyphosate resistance gives a significant fitness lift to the weedy version of the common rice plant Oryza sativa.
ラウンドアップ and his coworkers modified cultivated rice varieties to make more EPSP synthase. They also crossed the modified rice with a weedy related. Their research was published in NewPhytologist 1..
The group then let offspring that were cross-bred to breed with one another, creating second generation hybrids which are genetically similar to their parents with the exception for the number of duplicates of the gene that codes for EPSP synthase. As one would expect, hybrids that had more copies of the gene were more likely to produce more tryptophan and have higher enzyme levels than their unmodified counterparts.
ラウンドアップ found that transgenic hybrids were more photogenic, produced more plants per plant and yielded 48-125 percent higher yields of seeds than the non-transgenic varieties.
Lu believes making weedy, aggressive rice more competitive could make it more difficult for farmers to recover from the harm caused by this insect.
Brian Ford-Lloyd (a UK plant geneticist) claims that if the EPSP-synthase gene is introduced into wild rice, then their genetic diversity that is vital to preserve could be at risk. The transgene could outcompete regular species. This is one of the most clear examples of plausible harmful effects [of GM crop on the environment."
The study also challenges the notion that genetically modified plants with extra copies of their genes are more safe than crops that have microorganism genes. "Our study proves that this isn't necessarily the case," says Lu.
According to some research this research suggests that the future regulation of genetically engineered crops needs to be reconsidered. "Some individuals are claiming that biosafety regulations are eased because we've reached an incredibly high level of confidence in the last two years of genetic engineering" says Ellstrand. "But the study demonstrates that the new technologies require careful examination."
