Tuesday, April 2, 2013

Symbiotic bacteria program daily rhythms in squid using light and chemicals

Apr. 2, 2013 ? Glowing bacteria inside squids use light and chemical signals to control circadian-like rhythms in the animals, according to a study to be published on April 2 in mBio?, the online open-access journal of the American Society for Microbiology.

The Hawaiian bobtail squid, Euprymna scolopes, houses a colony of Vibrio fischeri bacteria in its light organ, using the bacteria at night as an antipredatory camouflage while it ventures out to hunt. The results of the study show that, in addition to acting as a built-in lamp, the bacteria also control when the squid expresses a gene that entrains, or synchronizes, circadian rhythms in animals.

"To our knowledge, this is the first report of bacteria entraining the daily rhythms of host tissues," says corresponding author Margaret McFall-Ngai of the University of Wisconsin -- Madison. If bacteria can entrain daily rhythms in an animal, McFall-Ngai says, it's reasonable to think these influences will eventually be found in other animals. It's possible that microbial partners in the human gut, for instance, could similarly influence human daily rhythms through chemical signaling.

Like all animals, squids make proteins that set their inner clock to environmental light. E. scolopes produces two of these "light entrainment" proteins (cryptochromes, or CRYs), and one is regulated in the squid's head, just like every other animal. McFall-Ngai and her co-authors noticed that escry1, the gene that encodes the other protein, is most highly expressed in the light organ, where the squid houses its glowing bacterial symbionts. "The animal uses the luminescence in the evening, so the luminescence is greatest at night. The gene escry1 cycles with the bioluminescence of the animal and not with environmental light," says McFall-Ngai.

But is it the bacterial luminescence that synchronizes the cycling, or is it the bacteria themselves? It's both, says McFall-Ngai.

The bacteria are necessary for cycling, she says, since squid grown without their bacterial symbionts do not cycle their expression of escry1, and mimicking the bacterial light with a blue light did not induce the cycling.

And they showed that the light is also necessary, because squids grown with defective V. fischeri symbionts that lack the ability to luminesce didn't cycle their expression of escry1 either. With light-defective bacteria in their light organs, squids exposed to the blue light got back on track, cycling escry1 production as usual.

What is it about the bacteria that could be signaling to the squid? Long experience taught McFall-Ngai where to turn next: microbe-associated molecular patterns (MAMPs), molecules that signal the presence of microbes to other creatures. "In this system we have found again and again that bacterial surface molecules are active at inducing all kinds of cellular behavior in the host," says McFall-Ngai.

Her hunch was right. MAMPs plus light turned cycling on. In squid grown without symbionts, light, combined with MAMPs (either the lipid A component of lipopolysaccharide or the peptidoglycan monomer), could induce some degree of cycling. The squid did not respond fully, though, maybe because the MAMPs were only injected into their seawater habitat, not presented directly to the light organ.

The fact that a bacterium can control a daily rhythm in a squid is exciting for other areas of biology, says McFall-Ngai, because all animals, including humans, have clock genes like escry1.

"Recently, in two different studies, biologists have found that there is profound circadian rhythm in both the epithelium [of the human gut] and the mucosal immune system of the gut that is controlled by these clock genes. What are we missing? Are the bacteria affected by or inducing the cycling of the tissues with which they associate?" We don't know," says McFall-Ngai, but it's an area ripe for study.

Moving forward with the squid symbiosis, McFall-Ngai says her lab will try to tie in the transcription of escry1 with cycling in the squid's metabolism to see what changes the squid actually experiences while it's under the spell of its bacterial symbionts.

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The above story is reprinted from materials provided by American Society for Microbiology, via EurekAlert!, a service of AAAS.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal Reference:

  1. Elizabeth A. C. Heath-Heckman, Suzanne M. Peyer, Cheryl A. Whistler, Michael A. Apicella, William E. Goldman and Margaret J. McFall-Ngai. Bacterial Bioluminescence Regulates Expression of a Host Cryptochrome Gene in the Squid-Vibrio Symbiosis. mBio, 2013; DOI: 10.1128/mBio.00167-13

Note: If no author is given, the source is cited instead.

Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/top_news/~3/ewKxwMhY9ms/130402091646.htm

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AP IMPACT: Cartels dispatch agents deep inside US

In this Feb. 14, 2013 photo, Art Bilek, executive vice president of the Chicago Crime Commission, left, announces that Joaquin ``El Chapo'' Guzman, a drug kingpin in Mexico, has been named Chicago's Public Enemy No. 1, during a news conference in Chicago. Looking on is Jack Riley, right, head of the Drug Enforcement Administration in Chicago and Peter Bensinger, former Administrator of the United States DEA. Ruthless drug cartels have long been the nation?s No. 1 supplier of illegal drugs, but in the past, their operatives rarely ventured beyond the border. A wide-ranging Associated Press review of federal court cases and government drug-enforcement data, plus interviews with many top law enforcement officials, indicate the groups have begun deploying agents from their inner circles to the U.S. (AP Photo/M. Spencer Green)

In this Feb. 14, 2013 photo, Art Bilek, executive vice president of the Chicago Crime Commission, left, announces that Joaquin ``El Chapo'' Guzman, a drug kingpin in Mexico, has been named Chicago's Public Enemy No. 1, during a news conference in Chicago. Looking on is Jack Riley, right, head of the Drug Enforcement Administration in Chicago and Peter Bensinger, former Administrator of the United States DEA. Ruthless drug cartels have long been the nation?s No. 1 supplier of illegal drugs, but in the past, their operatives rarely ventured beyond the border. A wide-ranging Associated Press review of federal court cases and government drug-enforcement data, plus interviews with many top law enforcement officials, indicate the groups have begun deploying agents from their inner circles to the U.S. (AP Photo/M. Spencer Green)

In this Dec. 11, 2012 file photo, Jack Riley, head of the Drug Enforcement Administration in Chicago, points out local Mexican drug cartel problem areas on a map in the new interagency Strike Force office in Chicago. Looking on is DEA agent Vince Balbo. The ruthless syndicates have long been the nation?s No. 1 supplier of illegal drugs, but in the past, their operatives rarely ventured beyond the border. A wide-ranging Associated Press review of federal court cases and government drug-enforcement data, plus interviews with many top law enforcement officials, indicate the groups have begun deploying agents from their inner circles to the U.S. (AP Photo/M. Spencer Green, File)

This 2009 photo provided by the Gwinnett County Sheriff's Department in Lawrenceville, Ga., shows reputed cartel operative Socorro Hernandez-Rodriguez after his arrest in a suburb of Atlanta. Hernandez-Rodriguez was later convicted of sweeping drug trafficking charges. Prosecutors said he was a high-ranking figure in the La Familia cartel, sent to the U.S. to run a drug cell. His defense lawyers denied he was a major figure in the cartel. (AP Photo/Courtesy of the Gwinnett County Sheriff?s Department)

This photo dated in 2007 from federal court documents provided by attorneys for Jose Gonzales-Zavala shows Gonzales-Zavala with two of his children allegedly taken in Mexico. Prosecutors say Gonzales-Zavala was a member of the La Familia cartel, based in southwestern Mexico, and dispatched to the Chicago area to oversee one of the cartel's lucrative trafficking cells. His defense team entered the photograph into evidence during the sentence stage of his case in arguing for leniency. In 2011, he was sentenced to 40 years in prison by a federal judge in Chicago. (AP Photo/Attorneys for Jose Gonzales-Zavala)

FILE - In this Oct. 22, 2009 file photo, weapons and drugs seized in special joint operation conducted with the Drug Enforecement Administration against the La Familia drug cartel based out of Michoacan, Mexico and operating in San Bernardino and surrounding counties, are on display at a news conference at sheriff's headquarters in San Bernardino, Calif. Drug cartels have long been the nation?s No. 1 supplier of illegal drugs, but in the past, their operatives rarely ventured beyond the border. A wide-ranging Associated Press review of federal court cases and government drug-enforcement data, plus interviews with many top law enforcement officials, indicate the groups have begun deploying agents from their inner circles to the U.S. (AP Photo/Reed Saxon, File)

(AP) ? Mexican drug cartels whose operatives once rarely ventured beyond the U.S. border are dispatching some of their most trusted agents to live and work deep inside the United States ? an emboldened presence that experts believe is meant to tighten their grip on the world's most lucrative narcotics market and maximize profits.

If left unchecked, authorities say, the cartels' move into the American interior could render the syndicates harder than ever to dislodge and pave the way for them to expand into other criminal enterprises such as prostitution, kidnapping-and-extortion rackets and money laundering.

Cartel activity in the U.S. is certainly not new. Starting in the 1990s, the ruthless syndicates became the nation's No. 1 supplier of illegal drugs, using unaffiliated middlemen to smuggle cocaine, marijuana and heroin beyond the border or even to grow pot here.

But a wide-ranging Associated Press review of federal court cases and government drug-enforcement data, plus interviews with many top law enforcement officials, indicate the groups have begun deploying agents from their inner circles to the U.S. Cartel operatives are suspected of running drug-distribution networks in at least nine non-border states, often in middle-class suburbs in the Midwest, South and Northeast.

"It's probably the most serious threat the United States has faced from organized crime," said Jack Riley, head of the Drug Enforcement Administration's Chicago office.

The cartel threat looms so large that one of Mexico's most notorious drug kingpins ? a man who has never set foot in Chicago ? was recently named the city's Public Enemy No. 1, the same notorious label once assigned to Al Capone.

The Chicago Crime Commission, a non-government agency that tracks crime trends in the region, said it considers Joaquin "El Chapo" Guzman even more menacing than Capone because Guzman leads the deadly Sinaloa cartel, which supplies most of the narcotics sold in Chicago and in many cities across the U.S.

Years ago, Mexico faced the same problem ? of then-nascent cartels expanding their power ? "and didn't nip the problem in the bud," said Jack Killorin, head of an anti-trafficking program in Atlanta for the Office of National Drug Control Policy. "And see where they are now."

Riley sounds a similar alarm: "People think, 'The border's 1,700 miles away. This isn't our problem.' Well, it is. These days, we operate as if Chicago is on the border."

Border states from Texas to California have long grappled with a cartel presence. But cases involving cartel members have now emerged in the suburbs of Chicago and Atlanta, as well as Columbus, Ohio, Louisville, Ky., and rural North Carolina. Suspects have also surfaced in Indiana, Michigan, Minnesota and Pennsylvania.

Mexican drug cartels "are taking over our neighborhoods," Pennsylvania Attorney General Kathleen Kane warned a legislative committee in February. State Police Commissioner Frank Noonan disputed her claim, saying cartels are primarily drug suppliers, not the ones trafficking drugs on the ground.

For years, cartels were more inclined to make deals in Mexico with American traffickers, who would then handle transportation to and distribution within major cities, said Art Bilek, a former organized crime investigator who is now executive vice president of the crime commission.

As their organizations grew more sophisticated, the cartels began scheming to keep more profits for themselves. So leaders sought to cut out middlemen and assume more direct control, pushing aside American traffickers, he said.

Beginning two or three years ago, authorities noticed that cartels were putting "deputies on the ground here," Bilek said. "Chicago became such a massive market ... it was critical that they had firm control."

To help fight the syndicates, Chicago recently opened a first-of-its-kind facility at a secret location where 70 federal agents work side-by-side with police and prosecutors. Their primary focus is the point of contact between suburban-based cartel operatives and city street gangs who act as retail salesmen. That is when both sides are most vulnerable to detection, when they are most likely to meet in the open or use cellphones that can be wiretapped.

Others are skeptical about claims cartels are expanding their presence, saying law-enforcement agencies are prone to exaggerating threats to justify bigger budgets.

David Shirk, of the University of San Diego's Trans-Border Institute, said there is a dearth of reliable intelligence that cartels are dispatching operatives from Mexico on a large scale.

"We know astonishingly little about the structure and dynamics of cartels north of the border," Shirk said. "We need to be very cautious about the assumptions we make."

Statistics from the DEA suggest a heightened cartel presence in more U.S. cities. In 2008, around 230 American communities reported some level of cartel presence. That number climbed to more than 1,200 in 2011, the most recent year for which information is available, though the increase is partly due to better reporting.

Federal agents and local police say they have become more adept at identifying cartel members or operatives using wiretapped conversations, informants or confessions. Hundreds of court documents reviewed by the AP appear to support those statements.

"This is the first time we've been seeing it ? cartels who have their operatives actually sent here," said Richard Pearson, a lieutenant with the Louisville Metropolitan Police Department, which arrested four alleged operatives of the Zetas cartel in November in the suburb of Okolona.

People who live on the tree-lined street where authorities seized more than 2,400 pounds of marijuana and more than $1 million in cash were shocked to learn their low-key neighbors were accused of working for one of Mexico's most violent drug syndicates, Pearson said.

One of the best documented cases is Jose Gonzalez-Zavala, who was dispatched to the U.S. by the La Familia cartel, according to court filings.

In 2008, the former taxi driver and father of five moved into a spacious home at 1416 Brookfield Drive in a middle-class neighborhood of Joliet, southwest of Chicago. From there, court papers indicate, he oversaw wholesale shipments of cocaine in Illinois, Wisconsin and Indiana.

Wiretap transcripts reveal he called an unidentified cartel boss in Mexico almost every day, displaying the deference any midlevel executive might show to someone higher up the corporate ladder. Once he stammered as he explained that one customer would not pay a debt until after a trip.

"No," snaps the boss. "What we need is for him to pay."

The same cartel assigned Jorge Guadalupe Ayala-German to guard a Chicago-area stash house for $300 a week, plus a promised $35,000 lump-sum payment once he returned to Mexico after a year or two, according to court documents.

Ayala-German brought his wife and child to help give the house the appearance of an ordinary family residence. But he was arrested before he could return home and pleaded guilty to multiple trafficking charges. He will be sentenced later this year.

Socorro Hernandez-Rodriguez was convicted in 2011 of heading a massive drug operation in suburban Atlanta's Gwinnett County. The chief prosecutor said he and his associates were high-ranking figures in the La Familia cartel ? an allegation defense lawyers denied.

And at the end of February outside Columbus, Ohio, authorities arrested 34-year-old Isaac Eli Perez Neri, who allegedly told investigators he was a debt collector for the Sinaloa cartel.

An Atlanta attorney who has represented reputed cartel members says authorities sometimes overstate the threat such men pose.

"Often, you have a kid whose first time leaving Mexico is sleeping on a mattress at a stash house playing Game Boy, eating Burger King, just checking drugs or money in and out," said Bruce Harvey. "Then he's arrested and gets a gargantuan sentence. It's sad."

Typically, cartel operatives are not U.S. citizens and make no attempt to acquire visas, choosing instead to sneak across the border. They are so accustomed to slipping back and forth between the two countries that they regularly return home for family weddings and holidays, Riley said.

Because cartels accumulate houses full of cash, they run the constant risk associates will skim off the top. That points to the main reason cartels prefer their own people: Trust is hard to come by in their cutthroat world. There's also a fear factor. Cartels can exert more control on their operatives than on middlemen, often by threatening to torture or kill loved ones back home.

Danny Porter, chief prosecutor in Gwinnett County, Ga., said he has tried to entice dozens of suspected cartel members to cooperate with American authorities. Nearly all declined. Some laughed in his face.

"They say, 'We are more scared of them (the cartels) than we are of you. We talk and they'll boil our family in acid,'" Porter said. "Their families are essentially hostages."

Citing the safety of his own family, Gonzalez-Zavala declined to cooperate with authorities in exchange for years being shaved off his 40-year sentence.

In other cases, cartel brass send their own family members to the U.S.

"They're sometimes married or related to people in the cartels," Porter said. "They don't hire casual labor." So meticulous have cartels become that some even have operatives fill out job applications before being dispatched to the U.S., Riley added.

In Mexico, the cartels are known for a staggering number of killings ? more than 50,000, according to one tally. Beheadings are sometimes a signature.

So far, cartels don't appear to be directly responsible for large numbers of slayings in the United States, though the Texas Department of Public Safety reported 22 killings and five kidnappings in Texas at the hands of Mexican cartels from 2010 through mid- 2011.

Still, police worry that increased cartel activity could fuel heightened violence.

In Chicago, the police commander who oversees narcotics investigations, James O'Grady, said street-gang disputes over turf account for most of the city's uptick in murders last year, when slayings topped 500 for the first time since 2008. Although the cartels aren't dictating the territorial wars, they are the source of drugs.

Riley's assessment is stark: He argues that the cartels should be seen as an underlying cause of Chicago's disturbingly high murder rate.

"They are the puppeteers," he said. "Maybe the shooter didn't know and maybe the victim didn't know that. But if you follow it down the line, the cartels are ultimately responsible."

___

Follow Michael Tarm at www.twitter.com/mtarm .

Associated Press

Source: http://hosted2.ap.org/APDEFAULT/3d281c11a96b4ad082fe88aa0db04305/Article_2013-04-01-Cartels-Coming%20to%20America/id-c5632c7893744bd1931ed864dc864b32

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Shower Enclosure Shelf - DIY Home Improvement, Remodeling ...

Hi All,

I have a fiber glass shower insert and want to install a shelf. I have tried the suction cup things and the ceiling to floor tension rods and they don't work or we don't like them. Does anyone know where I can get a corner shelf that I can either screw into the wall or use epoxy or some type of strong glue?

Thanks

Source: http://www.houserepairtalk.com/f33/shower-enclosure-shelf-15785/

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Monday, April 1, 2013

Ask Engadget: best Android e-mail client?

Ask Engadget best Android email client

We know you've got questions, and if you're brave enough to ask the world for answers, then here's the outlet to do so. This week's Ask Engadget inquiry is from Saad, who's got wants some of that Mailbox goodness for himself. If you're looking to ask one of your own, drop us a line at ask [at] engadget [dawt] com.

"I've seen wonderful applications like Mailbox and Sparrow on iOS, which do the job and aren't too shabby in the looks department. Having used Sparrow on the iPad, I've been looking for an alternative that can be used on my Android phone. Any suggestions? Thanks!"

We can tell you're not a fan of the Gmail app, so what about alternatives? Well, perhaps something like Aqua Mail, MailDroid or K-9 Mail could float your ocean-going vessel. If not those, then maybe it's time to ask what the Engadget faithful use on their daily drivers, so have at it, friends.

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Comments

Source: http://feeds.engadget.com/~r/weblogsinc/engadget/~3/wODDCwJEG4w/

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Stocks are mixed on Wall Street after holiday

NEW YORK (AP) ? Stocks are mixed in early trading on Wall Street after the long Easter holiday weekend.

Markets were closed Friday in observance of Good Friday. European markets were still closed Monday for Easter.

The Dow Jones industrial average was up eight points, less than 0.1 percent, to 14,587 shortly after the opening bell.

The broader Standard & Poor's 500 index was up a fraction of a point at 1,569. The Nasdaq composite was up two points, 0.1 percent, at 3,270.

The yield on the benchmark 10-year Treasury note was little changed at 1.86 percent.

Asian markets finished mostly lower.

The Institute for Supply Management is expected to report that its manufacturing index grew for the fourth consecutive month in March, although at a slightly slower pace than in February.

Source: http://news.yahoo.com/stocks-mixed-wall-street-holiday-134352990--finance.html

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Cute Kid Note Of The Day: Dear Easter Bunny

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    Multi-toxin biotech crops not silver bullets, scientists warn

    Mar. 29, 2013 ? The popular new strategy of planting genetically engineered crops that make two or more toxins to fend off insect pests rests on assumptions that don't always apply, UA researchers have discovered. Their study helps explain why one major pest is evolving resistance much faster than predicted and offers ideas for more sustainable pest control.

    A strategy widely used to prevent pests from quickly adapting to crop-protecting toxins may fail in some cases unless better preventive actions are taken, suggests new research by University of Arizona entomologists published in the Proceedings of the National Academy of Sciences.

    Corn and cotton have been genetically modified to produce pest-killing proteins from the bacterium Bacillus thuringiensis, or Bt for short. Compared with typical insecticide sprays, the Bt toxins produced by genetically engineered crops are much safer for people and the environment, explained Yves Carri?re, a professor of entomology in the UA College of Agriculture and Life Sciences who led the study.

    Although Bt crops have helped to reduce insecticide sprays, boost crop yields and increase farmer profits, their benefits will be short-lived if pests adapt rapidly, said Bruce Tabashnik, a co-author of the study and head of the UA department of entomology. "Our goal is to understand how insects evolve resistance so we can develop and implement more sustainable, environmentally friendly pest management," he said. Tabashnik and Carri?re are both members of the UA's BIO5 Institute.

    Bt crops were first grown widely in 1996, and several pests have already become resistant to plants that produce a single Bt toxin. To thwart further evolution of pest resistance to Bt crops, farmers have recently shifted to the "pyramid" strategy: each plant produces two or more toxins that kill the same pest. As reported in the study, the pyramid strategy has been adopted extensively, with two-toxin Bt cotton completely replacing one-toxin Bt cotton since 2011 in the U.S.

    Most scientists agree that two-toxin plants will be more durable than one-toxin plants. The extent of the advantage of the pyramid strategy, however, rests on assumptions that are not always met, the study reports. Using lab experiments, computer simulations and analysis of published experimental data, the new results help explain why one major pest has started to become resistant faster than anticipated.

    "The pyramid strategy has been touted mostly on the basis of simulation models," said Carri?re. "We tested the underlying assumptions of the models in lab experiments with a major pest of corn and cotton. The results provide empirical data that can help to improve the models and make the crops more durable."

    One critical assumption of the pyramid strategy is that the crops provide redundant killing, Carri?re explained. "Redundant killing can be achieved by plants producing two toxins that act in different ways to kill the same pest," he said, "so, if an individual pest has resistance to one toxin, the other toxin will kill it."

    In the real world, things are a bit more complicated, Carri?re's team found out. Thierry Br?vault, a visiting scientist from France, led the lab experiments at the UA. His home institution, the Center for Agricultural Research for Development, or CIRAD, is keenly interested in factors that could affect pest resistance to Bt crops in Africa.

    "We obviously can't release resistant insects into the field, so we breed them in the lab and bring in the crop plants to do feeding experiments," Carri?re said. For their experiments, the group collected cotton bollworm -- also known as corn earworm or Helicoverpa zea -, a species of moth that is a major agricultural pest, and selected it for resistance against one of the Bt toxins, Cry1Ac.

    As expected, the resistant caterpillars survived after munching on cotton plants producing only that toxin. The surprise came when Carri?re's team put them on pyramided Bt cotton containing Cry2Ab in addition to Cry1Ac.

    If the assumption of redundant killing is correct, caterpillars resistant to the first toxin should survive on one-toxin plants, but not on two-toxin plants, because the second toxin should kill them, Carri?re explained.

    "But on the two-toxin plants, the caterpillars selected for resistance to one toxin survived significantly better than caterpillars from a susceptible strain."

    These findings show that the crucial assumption of redundant killing does not apply in this case and may also explain the reports indicating some field populations of cotton bollworm rapidly evolved resistance to both toxins.

    Moreover, the team's analysis of published data from eight species of pests reveals that some degree of cross-resistance between Cry1 and Cry2 toxins occurred in 19 of 21 experiments. Contradicting the concept of redundant killing, cross-resistance means that selection with one toxin increases resistance to the other toxin.

    According to the study's authors, even low levels of cross-resistance can reduce redundant killing and undermine the pyramid strategy. Carri?re explained that this is especially problematic with cotton bollworm and some other pests that are not highly susceptible to Bt toxins to begin with.

    The team found violations of other assumptions required for optimal success of the pyramid strategy. In particular, inheritance of resistance to plants producing only Bt toxin Cry1Ac was dominant, which is expected to reduce the ability of refuges to delay resistance.

    Refuges consist of standard plants that do not make Bt toxins and thus allow survival of susceptible pests. Under ideal conditions, inheritance of resistance is not dominant and the susceptible pests emerging from refuges greatly outnumber the resistant pests. If so, the matings between two resistant pests needed to produce resistant offspring are unlikely. But if inheritance of resistance is dominant, as seen with cotton bollworm, matings between a resistant moth and a susceptible moth can produce resistant offspring, which hastens resistance.

    According to Tabashnik, overly optimistic assumptions have led the EPA to greatly reduce requirements for planting refuges to slow evolution of pest resistance to two-toxin Bt crops.

    The new results should come as a wakeup call to consider larger refuges to push resistance further into the future, Carri?re pointed out. "Our simulations tell us that with 10 percent of acreage set aside for refuges, resistance evolves quite fast, but if you put 30 or 40 percent aside, you can substantially delay it."

    "Our main message is to be more cautious, especially with a pest like the cotton bollworm," Carri?re said. "We need more empirical data to refine our simulation models, optimize our strategies and really know how much refuge area is required. Meanwhile, let's not assume that the pyramid strategy is a silver bullet."

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    Story Source:

    The above story is reprinted from materials provided by University of Arizona. The original article was written by Daniel Stolte.

    Note: Materials may be edited for content and length. For further information, please contact the source cited above.


    Journal Reference:

    1. T. Brevault, S. Heuberger, M. Zhang, C. Ellers-Kirk, X. Ni, L. Masson, X. Li, B. E. Tabashnik, Y. Carriere. Potential shortfall of pyramided transgenic cotton for insect resistance management. Proceedings of the National Academy of Sciences, 2013; DOI: 10.1073/pnas.1216719110

    Note: If no author is given, the source is cited instead.

    Disclaimer: Views expressed in this article do not necessarily reflect those of ScienceDaily or its staff.

    Source: http://feeds.sciencedaily.com/~r/sciencedaily/~3/wYWT6YRzi0Y/130330130838.htm

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