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Wild plants may be able to resist herbicides.

Weedy rice may pick up transgenes from genetically modified crop rice by cross-pollinating. Credit: Xiao Yang
A genetic-modification technique used widely to make crops herbicide resistant has been found to confer advantages on the weedy rice even in absence of herbicide. This suggests that the benefits of such modifications could extend beyond the confines of farms out into the wild.

Many cultivars are genetically altered so that they can ward off glyphosate. The herbicide was initially available under the trade name Roundup. Farmers are able to eliminate weeds in their fields using glyphosate without harming their crops because of this resistance.

Glyphosate inhibits plant growth through blocking an enzyme, known as EPSP synthase, which is involved in the production of certain amino acids and other molecules that make up about 35% of the plant’s mass. The technique of genetic modification employed, for example, in Roundup Ready crops made by the biotechnology giant Monsanto which is headquartered in St Louis, Missouri -generally includes inserting genes into the crop’s genome to increase the production of EPSP synthase. The genes are typically derived from bacteria that are infected with plants.

The extra EPSP synase allows for the plant to resist the harmful effects of glyphosate. Biotechnology labs have also tried to use genes from plants rather than bacteria to increase EPSP-synthase levels, in part to exploit an inconsistency within US law that facilitates approval by regulators of organisms that have transgenes that are not made from bacterial pests.

A few studies have explored whether transgenes like those that confer resistance to glyphosate increase the competitiveness of plants in reproductive success and longevity once they’re introduced to wild or weedy cousins by cross-pollination. Norman Ellstrand of University of California Riverside states, “The conventional expectation is that any transgene in the wild will confer disadvantage if there’s no pressure to select because the extra machinery could reduce the fitness.”

ラウンドアップ Lu Baorong, an ecologist from Fudan University in Shanghai has rewritten that view. He has discovered that glyphosate resistance gives an impressive fitness boost to the weedy version of the common rice crop Oryza sativa. Lu and colleagues modified cultivated rice species to enhance the production of EPSP synthase. ラウンドアップ The modified rice was then crossed with a wild relative.

The team allowed the offspring of cross-breeding to mix with one another, resulting in second-generation hybrids genetically identical to one another, except for the amount of copies the gene that encodes EPSP synase. As was expected, those with more copies had greater levels of enzymes and produced more amino acid tryptophan when compared to their counterparts that were not modified.

The researchers also found that the transgenic hybrids had higher rates of photosynthesis.除草剤 ラウンドアップ 業務用/ They also grew more shoots and flowers and produced 48 to 125 percent more seeds per plant than non-transgenic hybridswith or without glyphosate.

Lu believes making weedy, aggressive rice more competitive could hinder farmers to repair the damage caused by this bug.

Brian Ford-Lloyd, a UK plant geneticist. He says, “If the EPSP synthase gene becomes present in wild rice varieties their genetic diversity will be endangered, which is crucial because the genotype that has transgene is superior to the natural species.” “This is among the most obvious examples of highly plausible harmful consequences of GM crops] on the environment.”

Many people believe that genetically modified plants containing more copies of their own genes than microorganisms are safe. This notion is also challenged by this study. Lu says that “our study doesn’t prove that this is true.”

The finding calls for a reconsideration of the future regulations for genetically modified crops, some scientists claim. ラウンドアップ “Some individuals are suggesting that biosafety regulation can be relaxed because we have a high level of comfort with the two years of genetic engineering” Ellstrand says. “But the research shows that novel products still need cautious evaluation.”