Sentences with phrase «bt toxin»

Part of the problem in bollworms developing resistance to the Bt toxin is over-cultivation of the GM crop, in the sense of planting too much of it close together and not providing so - called «refuge» space between fields and farms.

The Bt toxin being used in GMO corn, for example, was recently detected in the blood of pregnant women and their babies.

According to Dr. Mercola, it was reported that doctors in a hospital in Quebec (Canada) actually found Bt toxin in the blood of 93 % of pregnant women tested, 80 % of their babies, and almost 70 % of non-pregnant women.

Synthetic chemicals have largely been responsible for accomplishing the task but the agricultural industry has more recently started a biological warfare campaign against insects with an organism known as Bacillus thuringiensis, or the Bt toxin.

This study overturns the assumptions that Bt toxin is destroyed during digestion and is not biologically active in mammals.

Mice were fed with either GM potatoes engineered to produce Bt toxin or natural potatoes spiked with Bt toxin.

Genetic Roulette claims that effects seen by Fares and El - Sayed in 1998 with a traditional non-GM bacterial Bt toxin were also obtained with potatoes genetically manipulated to make that toxin.

Unlike typical broad - spectrum insecticides, which kill most insects, pests or not, the Bt toxin only targets certain insect species.

Based on laboratory experiments aimed at determining the molecular mechanisms involved, scientists knew that pink bollworm could evolve resistance against the Bt toxin, but they had to go all the way to India to observe this happening in the field.

Mutations that disrupt cadherin block this binding, which leaves the insect unscathed by the Bt toxin.

Binding of Bt toxin to cadherin is an essential step in the intoxication process.

Their findings, reported in the May 19 issue of the journal PLOS ONE, shed light on how the global caterpillar pest called pink bollworm overcomes biotech cotton, which was designed to make an insect - killing bacterial protein called Bt toxin.

The emergence of resistant pink bollworm in India provided the researchers an opportunity to test the hypothesis that insects in the field would evolve resistance to Bt toxin by the same genetic mechanism found previously in the lab.

Then the team let loose a special strain of diamondback moth pupa, some of which carried at least one copy of a resistance gene to the Bt toxin.

Companies selling Bt seeds hope to avoid that in part by designing plants that make more than one Bt toxin, but this strategy may not work if resistance to several toxins is tied to a single gene, says Tabashnik, who is now at the University of Arizona.

The modified crops pump out Bt toxin, a natural insecticide created by bacteria.

The idea is that insects in the refuges would remain vulnerable to Bt toxin, and the bugs would interbreed to keep the whole population susceptible.

If a host lacks galactosyltransferase, however, the Bt toxin cant locate the intestines and the worm sustains no damage to its internal composition.

In a second article appearing in the same journal, a team of geneticists studying the tobacco budworm moth discovered a recessive gene (BtR - 4) that provides resistance to Bt toxin.

Conventional growers also help to stop corn borers becoming resistant to the Bt toxin by hosting pest populations that are susceptible to it, according to the team's research.

The report was commissioned by India environment minister Jairam Ramesh, who earlier this year had imposed an indefinite moratorium on the release of brinjal engineered to make the Bt toxin that helps the plant resist insect pests.

Turlings's team is now looking into creating super-resistant maize by inserting the gene for caryophyllene into plants that are already engineered to produce the Bt toxin against rootworms.

Genetically modified (GMO) soybean oil, GMO sugar (Roundup Ready sugar beets), cottonseed oil (Bt Toxin GMO cotton), high fructose corn syrup (Roundup Ready and / or Bt Toxin GMO corn), and soy lecithin (Roundup Ready and / or Bt Toxin soybeans).

Organic growers have used Bt toxins in sprays for decades, and conventional farmers have widely adopted transgenic Bt crops since 1996.

Recognizing that resistance is not «all or none» and that intermediate levels of resistance can have a continuum of effects on pest control, the authors describe five categories of field - evolved resistance and use them to classify 13 cases of resistance to five Bt toxins in transgenic corn and cotton based on monitoring data from five continents for nine major pest species.

This will be critically important information as more crops are engineered to produce Bt toxins.»

Mario Sobern of the National Autonomous University of Mexico and his colleagues investigated the most commonly used Bt toxins, which work by binding to specific receptors in pest midguts.

But as the use of Bt toxins increases, so does the fear of developing Bt - resistant strains of insects.

The scientists speculate that crystalline Bt toxins recognize the outer surface of intestinal cells through carbohydrates and sugars.

Now something similar is happening with animal pests and Bt toxins, although the Bt crops are largely holding their own after about 15 years of global use: cases of resistance are rare, popping up only where farmers fail to cultivate correctly (see «Super-pests are fighting back against killer crops «-RRB-.

The finding, published in today's issue of the Proceedings of the National Academy of Sciences, boosts fears that some insects could quickly develop resistance to these pesticides, bacterial proteins known as Bt toxins, and render them useless.

Farmers are also trying to thwart resistance by growing plants that lack the Bt toxins near their fields, cultivating populations of normal insects that could swamp the resistance genes, says Randy Deaton, a Bt researcher at Monsanto, which developed some Bt crops.

In the U.S., pink bollworm populations have not evolved resistance to Bt toxins in the wild.

Not exact matches

A 2002 Greenpeace report, based on Chinese lab tests, found that the toxin level in Bt crops was severely «limited.»

Bt eggplant is genetically modified to produce toxins against the fruit and shoot borer.

The first transgenic crop likely to be put forward for approval for open trials and commercial release is Bt cotton — which has added genes from the Bacillus thuringiensis bacterium, making the plant produce toxins that confer resistance to some insect pests.

Comparing proteins produced by normal genes to those produced by mutant Bt resistant ones, the team discovered that enzymes play a key role in determining whether or not a worm succumbs to the toxin.

DNA analyses of the Oaxaca corn revealed several signs of gene transfer from transgenic plants, including a gene of Bacillus thuringiensis (Bt), a bacterium that produces a toxin lethal to common pests.

In a warmer world, the corn earworm may evolve resistance faster to Bt corn, a crop that has been genetically modified to produce an insect - killing toxin, researchers propose.

Some commercial varieties of corn have been engineered with genes for a toxin borrowed from the bacterium Bacillus thuringiensis, known as Bt, that kills the earworms when they eat the crop.

Genetically modified crops that produce the pest - killing toxin Bt increase yields and reduce the use of noxious chemical insecticides.

In South Africa, most farmers are still cultivating single - toxin Bt maize.

In the medium term, single - toxin Bt maize is being progressively replaced by a stacked variety producing two different toxins but, in a worst case scenario, one can not exclude that Busseola fusca could also quickly adapt to varieties expressing more than one toxin.

The active ingredient in the insecticide was a second toxin also derived from the same Bt bacteria.

In line with other known cases of Bt - resistance, resistance in Busseola fusca was expected to involve modification of the cells in the gut wall, which prevents the toxin from binding.

Among research that has faced industry disapproval, says Benbrook, are studies on evolving weed resistance, on plant pathogens, and on susceptibility of non-pest insects to the Bacillus thuringiensis (Bt)- derived toxins that protect the GM plants against insect pests.

Bt - toxin kills insects by destroying the lining of their digestive tracts.

Organic farmers actually use Bt - toxin - producing bacteria as an effective nematode control.

GMO Corn for example was combined with bacteria in order to produce its own insecticide, called Bt - toxin.

Bt - toxin was originally derived from bacteria, the DNA of which was combined with corn.