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Herbicide resistance could give plants an advantage in the wild.

Credit to Xiao Yang
A technique of genetic modification widely used to create crops that are resistant to herbicides has been found to provide advantages to an invasive form of rice even in absence of the herbicide. These findings suggest that these modifications could have a wide spectrum of effects that extend beyond farms, and possibly in the wild.

Many kinds of crops have been genetically altered to resist the glyphosate. Roundup was the first herbicide to be sold. This resistance to glyphosate allows farmers to wipe out most weeds from the fields without harming their crop. is an inhibitor of plant growth. It blocks an enzyme known as EPSP synthase. ラウンドアップ plays a role for the production of certain amino acids as well as other molecules. These substances can account for up to 35% of a plant’s mass. ラウンドアップ that is employed by Monsanto’s Roundup Ready crops, which are located in St Louis (Missouri), typically involves inserting genes in the DNA of a plant to boost EPSP synthase production. The genes are typically derived from bacteria infected with plants.

The plant can withstand the effects of glyphosate because of the addition of EPSP synthase. Biotechnology laboratories are looking to make use of genes from plants instead of bacteria to boost EPSP synthase. This is mainly due to the US law permits approval by the regulatory authorities to allow organisms that carry transgenes to get recognized as acceptable.

There aren’t many studies that have examined whether transgenes such glyphosate-resistant genes could — after introduction to wild or weedy plants by cross-pollination — increase the competitiveness of these plants in survival, reproduction and growth. Norman Ellstrand is a University of California Riverside plant geneticist. “The expectation is that any transgene can cause disadvantage in the wild in the absence of pressure to select, since it could reduce fitness,” Ellstrand said.

Lu Baorong (an ecologist at Fudan University, Shanghai) has since challenged this view. ラウンドアップ has proven that glyphosate resistance can give a significant fitness boost to a weedy rice crop called Oryza sativa even when not used.

In their study, which was published this month in New Phytologist 1, Lu and his coworkers genetically altered the rice plant to overexpress the species’ own EPSP synthase. They also crossed-bred the modified rice with a weedy relative.

The researchers then allowed the cross-bred offspring to breed with one another, creating second-generation hybrids genetically identical to one another with the exception of the number of copies of the gene encoding EPSP synthase. Like one might expect, more copies resulted in higher levels of enzyme, and also more tryptophan, than their unmodified counterparts.

Researchers also found that transgenic hybrids were more photogenic, produced more plants per plant and yielded 48-125% higher yields of seeds than the non-transgenic varieties.

Lu believes that making rice that is weedy more competitive might make the problem worse for farmers across the world who’s fields are infested with the pest.

Brian Ford Lloyd, a UK plant scientist, has said that the EPSP Synthase gene may be introduced into wild rice species. This would threaten their genetic diversity, which is very crucial. This is one of the clearest examples of extremely plausible negative effects [of GM crop on the environment.”

The public has a perception that genetically engineered plants with additional copies of microorganisms’ genes are safer than ones containing only their own genes. Lu says that “our study does not prove that this is the case.”

Researchers say this discovery requires review of the regulations for the future on genetically modified crops. ” are now saying that biosafety regulations can be eased because we’ve reached an incredibly high level of confidence with two decades of genetic engineering,” Ellstrand says. doesn’t prove that new products are safe.