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Archive for the ‘Research’ Category

The Secret of Dragonflies’ Flight
By controlling each of their four wings individually, dragonflies can manipulate fluid dynamics to execute a wide range of aerial maneuvers

Released: 14-Nov-2014 8:00 AM EST
Embargo expired: 23-Nov-2014 9:00 PM EST
Source Newsroom: American Physical Society’s Division of Fluid Dynamics

http://www.newswise.com/articles/view/626203/?sc=dwtn

dragonflies image (1)

Jane Wang research group, Cornell University
A collage of dragonflies during recovery flight. Yellow arrows indicate the body orientation, and the circles on the wings are tracked points, overlaid on top of the image.

 

 

 

 

Newswise — WASHINGTON, D.C., November 23, 2014 — Dragonflies can easily right themselves and maneuver tight turns while flying. Each of their four wings is controlled by separate muscles, giving them exquisite control over their flight.
Researchers from Cornell University are investigating the physics behind this ability by recording high-speed video footage of dragonflies in flight and integrating the data into computer models, and they will present their findings at the 67th annual meeting of the American Physical Society (APS) Division of Fluid Dynamics, held Nov. 23-25 in San Francisco.
“Dragonflies tend to have unpredictable flight — that’s what makes them fascinating. They hover for a bit, and every so often they’ll make a quick, sharp turn. They rarely stay right in front of your camera for us to contemplate on,” explained lead researcher Jane Wang.
In collaboration with Anthony Leonardo at Janelia Farm, the research campus of the Howard Hughes Medical Institute, Wang devised a unique experimental method to make dragonflies perform repeatable aerial maneuvers: to attach a tiny magnet to the underside of each insect that allowed them to hang upside down from a metal rod. When the magnet is released, said Wang, “Dragonflies somehow understand the orientation and they do a stereotypical maneuver: they roll their body to make a 180-degree turn.”
By tracking the body and wing orientations using high-speed video recording of this rapid roll in high resolutions, the team uncovered how dragonflies were altering the aerodynamics on their wings to execute the turn.
“The wings on an airplane are oriented at some fixed angle. But insects have freedom to rotate their wings,” explained Wang. By adjusting the wing orientation, dragonflies can change the aerodynamic forces acting on each of their four wings.
The iridescent insects can also change the direction in which they flap their wings — known technically as their “stroke plane.” The new data showed that dragonflies can adjust the stroke plane orientation of each wing independently.
With so many different variables, understanding how dragonflies control their flight is a complicated task. “Our job is to try to find out the key strategies that dragonflies use to turn,” explained Wang. She and her graduate student James Melfi Jr. are incorporating their data into a computer simulation of insects in free flight, which allows them to examine the separate effect of each kinematic change.
Wang described her group’s work as “using physical principles to explain animal behavior.”
“Even though biological organisms are complex, they still obey some basic laws — in this case, fluid dynamics. … I’m hoping to understand how these basic laws influence evolution of insects and the wiring of their neural circuitry.”
The presentation, “Roll Dynamics in a Free Flying Dragonfly,” was presented at 6:15 p.m. PT on Sunday, Nov. 23, 2014 in the Moscone West Convention Center, 2nd Floor Lobby. ABSTRACT: http://meetings.aps.org/Mehttp://meetings.aps.org/Meeting/DFD14/Session/F1.16eting/DFD14/Session/F1.16
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Wheat streak mosaic KSU(1)

Wheat streak mosaic virus is one of the most damaging and costly diseases wheat producers encounter, but plant pathologists have recently uncovered a way for the wheat plant to defend itself against this particular virus and others.

 

Helping Wheat Defend Itself Against Damaging Viruses

Patent-pending technology has shown success in disease resistance to wheat streak mosaic virus and triticum mosaic virus, among others.

Released: 18-Nov-2014 10:30 AM EST
Source Newsroom: Kansas State University Research and Extension

Newswise — MANHATTAN, Kan. – Wheat diseases caused by a host of viruses that might include wheat streak mosaic, triticum mosaic, soil-borne mosaic and barley yellow dwarf could cost producers 5 to 10 percent or more in yield reductions per crop, but a major advance in developing broad disease-resistant wheat is on the horizon.
John Fellers, molecular biologist for the U.S. Department of Agriculture’s Agricultural Research Service, and Harold Trick, plant geneticist for Kansas State University, have led an effort to develop a patent-pending genetic engineering technology that builds resistance to certain viruses in the wheat plant itself. And although genetically engineered wheat is not an option in the market today, their research is building this resistance in non-genetically engineered wheat lines as well.
“(Wheat viruses) are a serious problem,” Trick said. “Wheat streak mosaic virus is one of the most devastating viruses we have. It’s prevalent this year. In addition to that, we have several other diseases, triticum mosaic virus and soil-borne mosaic virus, that are serious diseases.”
Knowing how costly these diseases can be for producers, Fellers has worked on finding solutions for resistance throughout his career. As a doctoral student at the University of Kentucky, he used a technology in his research called pathogen-derived resistance, or RNA-mediated resistance—a process that requires putting a piece of a virus into a plant to make it resistant to that particular virus. Most of the viruses that infect wheat are RNA viruses, he said.
“The plant has its own biological defense system,” Fellers said. “We were just triggering that with this technology.”
Now Fellers, with the help of Trick, his wheat transformation facility and K-State graduate students, have developed transgenic wheat lines that contain small pieces of wheat streak mosaic virus and triticum mosaic virus RNA.
“It’s kind of like forming a hairpin of RNA,” Fellers said. “What happens is the plant recognizes this RNA isn’t right, so it clips a piece of it and chops it up, but then it keeps a copy for itself. Then we have a resistance element.”
Fellers compared the process to the old days of viewing most wanted posters on the post office wall. The piece of foreign RNA from the virus, which is a parasite, is one of those most wanted posters. Because the virus is a parasite, it has to seize or hijack part of the plant system to make proteins that it needs to replicate.
When the virus comes into the plant, the plant holds up that poster from the post office wall, recognizes the virus, and doesn’t allow the virus to replicate and go through its lifecycle.
A broad resistance goal
Trick said it wasn’t difficult to incorporate the RNA into the wheat, as it involved a standard transformation process where the DNA encoding the RNA was introduced into plant cells, plants were regenerated from these transformed cells, and then the transgenic plants underwent testing for disease resistance.
“The problem with this technology is the most wanted poster is only for one individual,” Trick added. “If we were trying to target multiple genes, we’d have to make another vector for a second virus, then create that transgenic, which we have done. So, we have different plants that are genetically resistant to wheat streak mosaic virus and plants that are resistant to triticum mosaic virus. We would like to get something that has broad resistance to many different viruses.”
Knowing again that the viruses are parasites that rely on part of the plant system to replicate, it may be possible to shut off these plant systems to prevent viral replication, Trick said, which in essence means making a most wanted poster for specific plant genes.
Fellers and Trick have made additional transgenic plants with a most wanted poster for these plant genes and tested their new plants for resistance to a number of wheat viruses.
“We’re now able to target barley yellow dwarf and soil-borne mosaic viruses,” Fellers said. “We’ve also done mixed infection tests with wheat streak mosaic and triticum mosaic (viruses), and our initial results now are that they’re all resistant. We’re very cautious, but our initial indications show we have come up with something that provides broad resistance to these four viruses. We thought it was important enough to file for a patent.”
Fellers said this work is a proof of concept, meaning it shows that researchers have an ability now to address these virus issues. The fact that the process uses genetic engineering would mean that getting broad-resistance wheat would take some time considering the public and industry would have to accept it first.
However, Trick said they are now pursuing a non-genetically engineered method that involves turning off specific plant genes using mutations. With this method, the researchers could develop the technology and incorporate it into the K-State breeding program without regulations.
“We would hope the turn around time would be quick, but it’s still classical breeding,” Fellers said of using mutations. “It’s a matter of developing markers and getting them in the varieties. We have been using Jagger and Karl 92, varieties that are already past their prime, so we have to get them in some newer varieties.”
The Kansas Wheat Commission has provided funding for this research. More information about K-State’s Department of Plant Pathology is available online (http://www.plantpath.ksu.edu). A video interview with Fellers and Trick can be found on the K-State Research and Extension YouTube page (http://youtu.be/mXiw78MpS0E).

 

 

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NEWS Science and Environment

7 October 2014 Last updated at 12:39 ET

By Claire Marshall
BBC environment correspondent

A closer look at how a tree injection works

Injecting trees with a concentrated form of garlic might help save trees in the UK from deadly diseases.

Operating under an experimental government licence, a prototype piece of technology to administer the solution is being trialled on a woodland estate in Northamptonshire.

Widespread use of the injection process is impractical and expensive.

But it could potentially help save trees of historic or sentimental value.

Garlic is one of nature’s most powerful antibacterial and antifungal agents.

It contains a compound called allicin, which scientists are interested in harnessing.

The experimental injection device is made up of a pressurised chamber and eight “octopus” tubes.

The pressure punches the solution through the tubes and through special injection units in to the tree’s sap system. The needles are positioned in a way to get allicin evenly around the tree.

The moment the active agent starts to encounter the disease, it destroys it. The poison is organic and isn’t rejected by the tree.

tree injection_78065849_78065848Tree injection

The treatment could potentially help save trees of historic or sentimental value
It is pulled up the trunk out along the branches and in to the leaves by the process of transpiration – the flow of water through a plant.

Tree consultant Jonathan Cocking is involved with the development and deployment of the treatment.

“Over the last four years we have treated 60 trees suffering badly with bleeding canker of horse chestnut. All of the trees were cured.

This result has been broadly backed up by 350 trees we have treated all over the country where we have had a 95% success rate.”

Oak trees with acute oak decline – which eventually kills the tree – have improved after being treated. In laboratory conditions allicin kills the pathogen chalara which is responsible for ash dieback.

The solution is made by a company in Wales. “Organic cloves of garlic are crushed,” said Mr Cocking, “and a patented method is used to amplify the volume of allicin and improve the quality of it so it is stable for up to one year. Allicin in the natural world only lasts for about 5-10 minutes.

If you go back to the tree the day after, and crush a leaf that is in the extremity of the crown, you can often smell the garlic.”

The goal is to get a commercial licence by the beginning of next year.

According to Prof Stephen Woodward, a tree expert at Aberdeen University: “The antibacterial properties of allicin are well-known in the laboratory. I have not heard of it being used in trees before, but yes this is interesting. It could work.”

However Mr Woodward cautioned about such methods of “biological control”. “Despite being plant-based that doesn’t mean it can’t harm an ecosystem. For example cyanide is plant-based.”

Many conservationists also caution against such drastic intervention. Dr Anne Edwards from the John Innes Centre was one of the first to identify ash dieback in a coppice wood in Norfolk.

She said that this treatment would not be effective for ash dieback: “In a woodland setting we really have to let nature take its course. It’s very depressing,” she explained.

The Woodland Trust also favours a different approach. The organization is investing £1.5m in a seed bank. The idea is to grow trees that are fully traceable and therefore free from foreign disease.

Austin Brady, director of conservation and external affairs, said: “Our native woodland needs to build its resilience to disease and pests. By starting from the beginning of the supply chain we can ensure that millions of trees will have the best possible chance of survival in the long term.”

In recognition of the threat posed by current and future tree and plant biosecurity, Defra recently appointed a Chief Plant Health Officer, and has earmarked £4 million for research in to treatments.

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http://www.scidev.net/global/farming/news/cheap-chemicals-entice-caterpillar-eating-wasps-to-crops.html

8B16D57EC04D470B1ECDE2E20E9DC85A image credit: Flickr/CIMMYT

Speed read
Plant growth promoters are already used to boost crop yields

Applying them early could also attract caterpillar-eating wasps

The researchers say seeds could be soaked in the chemicals before planting

[CAIRO] It may be a win-win situation: treating seeds with commercially available growth promoters before planting could have the added benefit of attracting parasitic wasps that feed on caterpillar pests, suggests a study.

The protective effect of these cheap, commercially available chemicals, known as ‘plant strengtheners’, can help protect young crops when they are particularly vulnerable to caterpillars, according to research published last month (19 February) in the Philosophical Transactions of the Royal Society B.

“In the new study we show that the effect is long-lasting: even a week after treatment, we can see the effect,” says study co-author Ted Turlings, an ecologist at the University of Neuchâtel, Switzerland.
——————————————————————————–
“This is an excellent pest control strategy.”

Mohamed Ragaei, Egyptian National Research Centre

———————————————————————————
It is estimated that pathogens and pests account for 25 to 40 per cent of total crop loss. When under attack, plants naturally emit oils that attract the natural predators of the pests. It is possible to up-regulate this process — so more oil is emitted— using genetic modification.

But genetic modification up-regulates only the production of specific chemicals, and research indicates that it is a mixture of various chemicals that is most effective at attracting predators.

Since the mid-2000s scientists have known that spraying with plant strengtheners — a generic term for compounds that boost the vigour, resilience and performance of crops — also elicits the release of a range of extra predator-attracting chemicals. Though the exact biology involved is not well understood and the technique had not performed well in field trials.

Turlings team thought that this poor performance during previous large trials might be partly because the strengtheners were applied too late and partly because heavily pest-infested fields were used for the trials. If this was the case, then the strengtheners could still be useful if applied earlier — by soaking seeds in them, for example.

The scientists tried this idea out on a small scale in their study; soaking maize seeds in two kinds of strengtheners for 12 hours, planting them, and — after a few days growth — counting how many wasps they attracted as compared with control seeds soaked in water. They found that plants treated with both kinds of strengthener, compounds known as BTH and laminarin, attracted more wasps than the controls. They say larger scale trials should now go ahead.

The researchers still do not know exactly how the growth promoters increase the attraction of the parasitic wasps. But they say that treating plants with them may be the most environmentally friendly and effective option available to simultaneously increase crop yields and attract pest predators. It is also cheaper and less controversial than genetic modification of seeds.

“I could imagine that cheap versions of the plant strengtheners could be used by subsistence farmers to boost the performance of their crops,” says Turlings.

Entomologist Mohamed Ragaei of the Egyptian National Research Centre in Cairo tells SciDev.Net that the approach looks “really promising”.

“This is an excellent pest control strategy,” he says. “Especially as the statistics show perfectly the effectiveness of a naturally treated plant to attract parasitoids and enhance the [oil] emissions.”

Link to abstract in Philosophical Transactions of the Royal Society B
References
Philosophical Transactions of the Royal Society B doi:10.1098/rstb.2012.0283 (2013)

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Phys.Org

Aug 22,2014

http://phys.org/news/2014-08-virus-dna.html

dnaplantscanswi

A team of virologists and plant geneticists at Wageningen UR has demonstrated that when tomato plants contain Ty-1 resistance to the important Tomato yellow leaf curl virus (TYLCV), parts of the virus DNA (the genome) become hyper-methylated, the result being that virus replication and transcription is inhibited. The team has also shown that this resistance has its Achilles heel: if a plant is simultaneously infected with another important (RNA) virus, the Cucumber mosaic virus (CMV), the resistance mechanism is compromised.

Antiviral defence via RNAi
Plant defence to viruses usually depends on RNA interference (RNAi). The genetic material of many viruses consists of RNA. A complex process in the plant causes the virus RNA to be chopped up into pieces, which means the virus can no longer multiply. In contrast to most other disease-causing plant viruses, the genetic material in TYLCV is DNA, not RNA. Therefore antiviral RNAi defence to these viruses has to happen somewhat different.

TYLCV is one of the most economically important plant viruses in the world; for this virus a number of resistance genes (Ty-1 to Ty-6) are available to commercial plant breeders. In 2013 the researchers in Wageningen succeeded in identifying and cloning the Ty-1 gene, which happened to present a member from an important class of RNAi-pathway genes. This led to a publication in PLoS Genetics. Their recent publication in the journal PNAS shows that although Ty-1 resistance depends on RNAi, instead of the genetic material being chopped up, it is being ‘blocked’ by methylation of the virus DNA.

No cross protection
A well-known phenomenon in the plant world is the ‘immunisation’ of plants by infecting them with relatively harmless viruses. The latter ensures that the defence mechanisms in plants are activated and provide ‘cross protection’ against more harmful, related viruses.

To their great surprise, the Wageningen researchers discovered that infection with CMV, a virus that contains RNA as genetic material and that, as a result, is not affected by the Ty-1 resistance mechanism, actually compromised resistance to the TYLCV virus. According to the researchers, this is a warning to plant breeders. The use of the Ty-1 gene does provide resistance, but the mechanism will be at risk in plants grown in greenhouses and fields if the plants are attacked by various other types of viruses.

Explore further: Virus rounds up enzymes, disarms plant
More information: Patrick Butterbach, Maarten G. Verlaan, Annette Dullemans, Dick Lohuis, Richard G. F. Visser, Yuling Bai, and Richard Kormelink. “Tomato yellow leaf curl virus resistance by Ty-1 involves increased cytosine methylation of viral genomes and is compromised by cucumber mosaic virus infection.” PNAS 2014 ; published ahead of print August 18, 2014, DOI: 10.1073/pnas.1400894111
Journal reference: PLoS Genetics Proceedings of the National Academy of Sciences
Provided by Wageningen University

Read more at: http://phys.org/news/2014-08-virus-dna.html#jCp

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PUBLIC RELEASE DATE: 3-Jul-2014

Contact: Caroline Wood
cwood4@sheffield.ac.uk
44-7771-765335
Society for Experimental Biology

http://www.eurekalert.org/pub_releases/2014-07/sfeb-owh062714.php

 

Many modern crops have high productivity, but have lost their ability to produce certain defence chemicals, making them vulnerable to attack by insects and pathogens. Swiss scientists are exploring ways to help protect 21st century maize by re-arming it with its ancestral chemical weapons.

The researchers, led by Dr Ted Turlings (University of Neuchâtel, Switzerland), found that many varieties of modern maize have lost their ability to produce a chemical called E-β-caryophyllene. This chemical is normally produced by traditional ancestors of modern maize roots when the plant is under attack from invading corn rootworms. The chemical attracts ‘friendly’ nematode worms from the surrounding soil which, in turn, kill the corn rootworm larvae within a few days.

The scientists used genetic transformation to investigate if restoring E-β-caryophyllene emission would protect maize plants against corn rootworms. After introducing a gene from oregano, the transformed maize plants released E- β-caryophyllene constantly. As a result, these plants attracted more nematodes and suffered less damage from an infestation of Western Corn Rootworms.

“Plant defences can be direct, such as the production of toxins, or indirect, using volatile substances that attract the natural enemies of the herbivores” says lead scientist, Dr Ted Turlings (University of Neuchâtel, Switzerland). One of the types of toxins that maize plants produce against their enemies is a class of chemicals called benzoxazinoids. These protect maize against a range of insects, bacteria and fungi pests, yet some species have developed resistance against these toxins and may even exploit them to identify the most nutritious plant tissues.

These results show how knowledge of natural plant defences can be practically applied in agricultural systems. “We are studying the wild ancestor of maize (teosinte) to find out which other chemical defences may have been lost during domestication of maize” Dr Turlings added. “These lost defences might then be reintroduced into modern cultivars”.

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PRI’s The World
Reporter Cynthia Graber
July 02, 2014 · 2:15 PM EDT

http://www.pri.org/stories/2014-07-02/future-agriculture-may-be-too-small-see-think-microbes

microbe2+

Thin filaments of fungi form a dense network between the roots of most of the world’s food crops. Some researchers believe that working with such microbes rather than against them, as has often been the case in conventional agriculture, will help the world grow more food with less environmental impact.

 

 

 

cassava

Geneticist Ian Sanders and his colleagues grew cassava in this field in Colombia using a fungal gel that he says improved yields by 20 percent. Cassava, which is native to Colombia, is one of the world’s most important food crops, feeding over a billion people.

 

Thin filaments of fungi form a dense network between the roots of most of the world’s food crops. Some researchers believe that working with such microbes rather than against them, as has often been the case in conventional agriculture, will help the world grow more food with less environmental impact.

Stick a shovel in the ground and you’ll dig up some soil, maybe a few little rocks and, of course, some roots.

Now — take those roots inside for a closer look and you’ll see something else as well.

“When you hold this thing up to the light, what you can see is little tiny filaments,” says geneticist Ian Sanders, holding up a root in his lab at the University of Lausanne in Switzerland.

The filaments look like tiny strands of cotton..

“That’s the fungus,” says Sanders.

Sanders is obsessed with fungi, because he thinks they can play a big role in solving the world’s big food challenges in a time of rapid climate change and population growth.

In particular, Sanders is obsessed with a type of fungi that live on the roots of about 80 percent of the plants on the planet. Their tiny filaments help plants grow by drawing water and nutrients to the plant. In return, the plants feed sugars to the fungi.

It’s a symbiotic relationship that Sanders says is incredibly important.

“Almost all our food plants naturally form this association with these fungi,” he says.

And these species of fungi aren’t alone. There are thousands, maybe millions of kinds of fungi, bacteria and other microbes that help plants in a variety of ways.

But their role has been almost invisible to people. In fact, critics say, modern agriculture actively works against them.

“What we’ve done over the last hundred years in agriculture, is to try to take microorganisms out of the picture,” says Seattle microbiologist Rusty Rodriguez.

“And by doing that, by disrupting the soil with tillage, by using chemical pesticides, we have greatly altered the agricultural microbiome.”

Rodriguez is also obsessed with fungi. And like Sanders, he wants to re-alter the agricultural mircobiome. Both are part of a growing field of researchers and entrepreneurs working to bring microorganisms like fungi back into the agricultural mix, but in a new and targeted way. Sanders is breeding new varieties in the lab, while Rodriguez’s company gathers fungi from extreme environments all over the US and cultivates them in their lab and greenhouse in Seattle.

Right now, Rodriguez is using the fungi to help grow tomatoes, soybeans and corn. His hope is that the microbes will help crops like these survive growing climate stresses like droughts and floods and extreme heat and cold.

Rodriguez is working with different kinds of fungi than Sanders. His grow throughout the plant, not just on roots. But his goal is the same — to find and develop fungi that make agriculture both more productive and more sustainable. And, he says, his first two products using these microbes are just about ready for prime time, with a possible launch later this year.

Sanders’s work isn’t quite there yet. He and his colleagues are still conducting field tests in places like Colombia. But he says the results so far have been very promising.

Columbia is home to cassava, a root crop that feeds more than a billion people around the world. Sanders and a group of Colombian researchers set up experimental plots there to grow cassava using a new fungal gel that they hoped would significant increase yields while significantly reducing fertilizer use.

When they harvested their first crop a year later, Sanders says, they were “delighted” by the results — the plants had grown up to 20 percent more roots.

Sanders says the result actually surprised him, but that it was just the beginning. The research team has since grown cassava with different varieties of lab-bred fungi, and so far, he says, the impact has been even more dramatic.

Rodriguez, in Seattle, shares Sanders’s bullish view of the future of agricultural fungi and bacteria.

“Biologics,” he believes, “are the next paradigm for agriculture.”

Of course we’ve heard talk like that before. Think chemical pesticides, synthetic fertilizers and GMOs, all of which brought big initial benefits, but also big environmental problems, or at least big concerns.

So far, there hasn’t been much push-back on biologics from environmentalists, but just because something’s natural doesn’t mean it’s safe. Which is why both Sanders and Rodriguez say they’re working to make sure the fungi they’re developing won’t bring any unwanted impacts.

“You have to know the organism is safe,” Rodriquez says. “I never want to be in a situation where I stand up in front of an audience and they ask me that question and I say ‘I don’t know.’”

What Rodriguez does know is that lots of tools will be needed to help produce more food, more sustainably.

And Sanders says we’ve been standing on some of those tools all along.

“Sometimes people think you have to go to unexplored wilderness to find something completely new,” Sanders says. “But we just have to look in the soil that’s beneath our feet.”

 

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