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The wild plants could have the advantage of resistance to herbicides.

Weedy rice can absorb transgenes derived from genetically modified crops through cross-pollination. ラウンドアップ Credit: Xiao Yang
A common method of genetic modification used to make crops more resistant to herbicides has been shown to offer advantages over rice varieties that are weedy. This indicates that these changes could be detrimental to the environment beyond farm.

A variety of kinds of crops have been genetically altered to resist glyphosate. ラウンドアップ Roundup was the first herbicide to be sold. ラウンドアップ This resistance to glyphosate permits farmers to get rid of weeds without causing any damage to their crops.

Glyphosate hinders growth of plants by blocking an enzyme referred to as EPSP synthase. This enzyme is involved in the creation of certain amino acids and other molecules that account for about 35% of the plant’s mass. The genetic modification method employed in 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 typically come from bacteria that infects plants.

ラウンドアップ ラウンドアップ The additional EPSP synthase lets the plant resist the effects of glyphosate. Biotechnology labs have also attempted to create EPSP-synthase that is more plant-based than bacteria using genes that come from plants. This was partially used to take advantage of an inconsistency found in US law, which permits the approval of regulatory authorities for organisms which aren’t the result of bacterial parasites.

Few studies have looked into whether transgenes, such as ones that confer resistance to the chemical glyphosate can help plants to be more resilient to surviving and reproduce once they cross-pollinate with weedy or wild species. Norman Ellstrand, a University of California plant geneticist, says that without competition, any type of transgene would be expected to confer disadvantage on wild plants. The added machinery will decrease fitness.

But now a study led by Lu Baorong, an ecologist at Fudan University in Shanghai, challenges that view It reveals that a weedy version of the popular rice plant, Oryza sativa is given an impressive fitness boost due to the resistance to glyphosate even when glyphosate has not been used.

In their study, which was published this month in New Phytologist 1, Lu and his colleagues genetically modified the rice plant to overexpress its own EPSP synthase. They crossed the altered rice with a weedy cousin.

The team allowed the offspring of crossbreeding to crossbreed with one another, resulting in second-generation hybrids that are genetically identical to one another, except for the amount of copies of the gene encoding EPSP synase. Likely, the ones with more copies expressed greater amounts of the enzyme, and produced more amino acid tryptophan than their non-modified counterparts.

Researchers also found that transgenic plants were more photosynthesis-intensive and produced more flowers and produced 48-125% fewer seeds per plant than non-transgenic hybrids. This was in spite of the fact that glyphosate was never present.

Lu believes that making weedy rice less competitive might make it more difficult for farmers who have their plots affected by pests.

Brian Ford-Lloyd, an UK plant geneticist who states, “If the EPSP synthase gene is introduced into wild rice varieties their genetic diversity could be at risk, which is significant because the genotype with transgene has a higher level of competition than the standard species.” “This is one example of the most plausible and damaging negative effects of GM crops on the environment.”

The general public believes that genetically engineered crops with additional copies of microorganisms’ genes are safer than ones containing only their own genes. Lu claims that the study does not support this notion. The research results call for a rethinking of future regulation of genetically modified crops, some scientists suggest. Ellstrand says that some people think that biosafety rules can be relaxed because we’ve had more than two years of genetic engineering. The study does not prove that new products are safe.