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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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USDA/Agricultural Research Service

http://www.ars.usda.gov/is/pr/2014/140218.htm

By Dennis O’Brien
February 18, 2014

ImageThis SoySNP50K iSelect SNP beadchip has 24 etched rectangles, which hold hundreds of thousands of microbeads, allowing detection of more than 50,000 bits of genetic information from a soybean DNA sample.

U.S. Department of Agriculture (USDA) researchers in Beltsville, Md. have developed a new tool to search for soybean genes that will make soybean plants more productive and better able to resist pests and diseases.

Scientists are constantly searching for genes to breed into soybeans that improve on disease resistance, yields, drought tolerance and other important characteristics. The tool was developed by Agricultural Research Service (ARS) scientists Perry Cregan, Qijian Song and Charles Quigley at the Soybean Genomics and Improvement Laboratory in Beltsville. Using the new tool, scientists can collect genetic information in three days that previously took weeks to gather.

The tool, called the SoySNP50K iSelect SNP BeadChip, is a glass chip about 3 inches long with an etched surface that holds thousands of DNA markers. The markers can be used to characterize the genomes of large numbers of soybean plants.

To create it, the researchers analyzed and compared the DNA of six cultivated and two wild soybean plants to identify single nucleotide polymorphisms (SNPs), a commonly used type of molecular marker. They compared SNPs from the eight soybean plants with sequences of a well-known cultivated variety and came up with thousands of gene markers to use as signposts when comparing genes of different soybean plants.

The researchers have used the chip to profile 96 wild and 96 cultivated soybean varieties by comparing SNP alleles, or variant forms, at each of their 52,000 positions on the soybean genome, as registered on the chip. They identified regions of the genome that played a key role in the plant’s domestication. Their results were published in PLOS One.

The researchers also used the chip to analyze the 18,484 cultivated soybean accessions and 1,168 wild soybean accessions in the USDA Soybean Germplasm Collection at Urbana, Ill., and submitted the data to the USDA-ARS soybean genetics and genomics database (known as SoyBase) so it can be accessed by breeders and geneticists.

ARS is USDA’s principal intramural scientific research agency, and this research supports the USDA priority of promoting international food security.

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Blunting Rice Disease
Researchers aim to disarm a ‘cereal killer’

Released: 6/2/2014 9:55 AM EDT
Source Newsroom: University of Delaware

http://www.newswise.com/articles/view/618683/?sc=dwtn

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This image shows, from top, rice that is not infected with the rice blast fungus; rice infected with rice blast; and infected rice treated with the beneficial microbe Pseudomonas chlororaphis EA105

Newswise — A fungus that kills an estimated 30 percent of the world’s rice crop may finally have met its match, thanks to a research discovery made by scientists at the University of Delaware and the University of California at Davis.
The research team, led by Harsh Bais, associate professor of plant and soil sciences in UD’s College of Agriculture and Natural Resources, has identified a naturally occurring microbe living right in the soil around rice plants — Pseudomonas chlororaphis EA105 — that inhibits the devastating fungus known as rice blast. What’s more, the beneficial soil microbe also induces a system-wide defense response in rice plants to battle the fungus.
The research, which is funded by the National Science Foundation, is published in BMC Plant Biology and includes, along with Bais, authors Carla Spence, a doctoral student in the Department of Biological Sciences, Emily Alff, who recently earned her master’s degree in plant and soil sciences, and Nicole Donofrio, associate professor of plant and soil sciences, all from UD; and Sundaresan Venkatesan, professor, Cameron Johnson, assistant scientist, and graduate student Cassandra Ramos, all from UC Davis.
“We truly are working to disarm a ‘cereal killer’ and to do so using a natural, organic control,” says Bais, in his laboratory at the Delaware Biotechnology Institute. In addition to rice, a distinct population of the rice blast fungus also now threatens wheat production worldwide.
“Rice blast is a relentless killer, a force to be reckoned with, especially as rice is a staple in the daily diet of more than half the world’s population — that’s over 3 billion people,” Bais notes. “As global population continues to grow, biocontrol bacteria may be an important key for farmers to overcome crop losses due to plant disease and to produce more food from the same acre of land.”
According to Bais, the rice blast fungus (Magnaporthe oryzae) attacks rice plants through spores resembling pressure plugs that penetrate the plant tissue. Once these spores infiltrate the cell wall, the fungus “eats the plant alive,” as Bais says. Common symptoms of rice blast are telltale diamond shaped-lesions on the plant leaves.
In order to do its work, the spore must produce a structure called the appressorium, a filament that adheres to the plant surface like an anchor. Without it, the fungus can’t invade the plant.
In a research study published in the journal Planta this past October, Bais and colleagues Spence, Donofrio and Vidhyavathi Raman showed that Pseudomonas chlororaphis EA105 strongly inhibited the formation of the appressorium and that priming rice plants with EA105 prior to infection by rice blast decreased lesion size.
For her work, Spence, the lead author, recently received the Carson Best Paper Award for the best scientific paper published by a Ph.D. student in biological sciences at UD.
The next step in the research was to sample the rhizosphere, the soil in the region around the roots of rice plants growing in the field, to reveal the microbial community living there and to attempt to elucidate their roles.
Thanks to DNA sequencing techniques, Bais says that identifying the various microorganisms in soil is easy. But understanding the role of each of those microorganisms is a continuing story.
A natural control for a deadly fungus
“Everyone knows what’s there, but we don’t know what they are doing,” Bais says of the microbes. To home in on the source of the antifungal impact, Bais and his colleagues are relying on what he refers to as “old school culturing” to find out if a single bacterium or a group of different bacteria are at work.
In their study reported in BMC Plant Biology, the researchers used gene sequencing techniques to identify 11 naturally occurring bacteria isolated from rice plants grown in the field in California. These bacteria were then tested in the laboratory, with Pseudomonas chlororaphis EA105 demonstrating the strongest impact on rice blast. The soil microbe reduced the formation of the anchor-like appressoria by nearly 90 percent while also inhibiting fungal growth by 76 percent.
Bais points out that although hydrogen cyanide is commonly produced by pseudomonad bacteria, the antifungal impact of Pseudomonas chlororaphis EA105 appears to be independent of cyanide production.
Applying a natural soil microbe as an antifungal treatment versus chemical pesticides offers multiple benefits to farmers and the environment, Bais says.
“Rice blast quickly learns how to get around synthetics — most manmade pesticides are effective only for about three years,” Bais says. “So it’s really cool to find a biological that can attenuate this thing.”
Bais, who also has conducted multiple studies with beneficial microbes in the Bacillus family, envisions a day when farmers will treat plants with a “magic cocktail of microbes” naturally found in soil to help boost their immunity and growth.
This summer, he and his colleagues will conduct field trials using Pseudomonas chlororaphis EA105 on rice plants grown on the UD farm. He also will work with farmers in the central states in India.
The research is supported by a $1.9 million grant from the National Science Foundation’s Plant Genome Research Project.

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Potential uses of small unmanned aircraft systems (UAS) in weed research

Authors
J Rasmussen, J Nielsen, F Garcia‐Ruiz, S Christensen, J C Streibig
First published: 10 May 2013 Full publication history
DOI: 10.1111/wre.12026

http://onlinelibrary.wiley.com/enhanced/doi/10.1111/wre.12026/?dmmsmid=85447&dmmspid=12417146&dmmsuid=2257923

Correspondence: J Rasmussen, Department of Plant and Environmental Sciences, Faculty of Science, University of Copenhagen, Højbakkegaard Allé 9, DK‐2630 Taastrup, Denmark. Tel: (+45) 35 33 34 56; Fax: (+45) 35 33 33 84; E‐mail: jer@life.ku.dk

Summary

Small unmanned aerial systems (UAS) with cameras have not been adopted in weed research, but offer low‐cost sensing with high flexibility in terms of spatial resolution. A small rotary‐wing UAS was tested as part of a search for an inexpensive, user‐friendly and reliable aircraft for practical applications in UAS imagery weed research. In two experiments with post‐emergence weed harrowing in barley, the crop resistance parameter, which reflects the crop response to harrowing, was unaffected by image capture altitude in the range from 1 to 50 m. This corresponded to image spatial resolution in the range from 0.3 to 17.1 mm per pixel. This finding is important because spatial resolution is inversely related to sensing capacity. We captured 20 plots comprising a total of about 0.2 ha in one image at 50 m altitude without losing information about the cultivation impacts on vegetation compared with ground truth data. UAS imagery also gave excellent results in logarithmic sprayer experiments in oilseed rape, where we captured 37 m long plots in each image from an altitude of 35 m. Furthermore, perennial weeds could be mapped from UAS images. These first experiences with a small rotary‐wing UAS show that it is relatively easy to integrate as a tool in weed research and offers great potential for site‐specific weed management.

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28 April 2014 Newcastle University

Bombarding pests with smells from many different plants temporarily confuses them and hinders their ability to feed, new research has shown.

Biologists at Newcastle University, UK, have been exploring the potential of harmless plant volatiles as an alternative to pesticides in greenhouses.

Testing a phenomenon known as the ‘confusion effect’ – whereby animals and humans become inefficient at a task when they are bombarded with lots of distracting information – the team pumped a mixture of plant smells into a greenhouse growing tomato plants.

Exposing the whitefly to a heady aroma of cucumber, courgette, watercress, watermelon, cabbage and bean, the team found the insects became temporarily disorientated.

Like other insect pests, whitefly feed by pushing their long mouthpiece – or stylets – into the leaf until it reaches the plant’s main source of nutrients travelling through the phloem. Weaving their way between the plant cells to reach the sap is technically challenging and the team found the whiteflies failed to feed while they were being bombarded with the different plant chemicals.

Publishing their findings this week in the academic journal Agronomy of Sustainable Development, research leads Dr Colin Tosh and Dr Barry Brogan said this method of control could be an important step towards a more sustainable method of pest control.

“It’s like trying to concentrate on work while the TV’s on and the radio’s blaring out and someone’s talking to you,” explains Dr Tosh, based in Newcastle University’s School of Biology. “You can’t do it – or at least not properly or efficiently – and it’s the same for the whitefly.

“Whiteflies use their sense of smell to locate tomato plants. By bombarding its senses with a range of different smells we create ‘sensory confusion’ and the result is that the insect becomes disorientated and is unable to feed.

“Because the effect is temporary – we saw it last no more than 15 hours – it’s unlikely this method alone could be used to control crop pests. But this is an easy and safe way of buying the plants time until their own chemical defence mechanisms kick in. Used in conjunction with other methods, sensory confusion opens up a whole new area in sustainable pest control.”

Trialeurodes vaporariorum – or whitefly – is a major worldwide pest of greenhouse crops and is traditionally controlled using chemical pesticides or biological methods such as parasites.

Previous studies have shown that whitefly become ‘restless’ when a number of plant species are mixed together rather than being exposed to a single crop. The aim of this latest research, funded by the Natural Environment Research Council (NERC), was to artificially create this mixed environment for a single crop greenhouse.

Measuring the time it took from the insect settling on a plant to accessing the plant sap, the team showed that hardly any of the whiteflies exposed to a range of smells started feeding from the phloem within 15 hours from the time of exposure. By comparison, the majority of whiteflies exposed to just the single smell released by the tomato plants started feeding within this time.

Dr Brogan, also based in the School of Biology, adds: “Plants talk to each other when they are under attack – producing chemicals which warn other plants close by of the threat. At the same time, they produce a chemical which is unpleasant to the predator.

“But this response doesn’t happen immediately, so if we can confuse the insects long enough to give the plants time to defend themselves this may go someway to reducing crop losses.”

The team have now started the next phase of the study to investigate ways of helping plants to talk to each other and better switch on their defences.

Full bibliographic information
“Control of tomato whiteflies using the confusion effect of plant odours”. Colin Tosh and Barry Brogan. Agronomy for Sustainable Development. DOI 10.1007/s13593-014-0219-4

http://www.alphagalileo.org/ViewItem.aspx?ItemId=141300&CultureCode=en&dm_i=1ANQ,2F2AB,6LPWNX,8SEQE,1

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Green vaccination: boosting plant immunity without side effects
Apr 29, 2014 by David Stacey

PHYS ORG

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(Phys.org) —A team of international researchers has uncovered a mechanism by which plants are able to better defend themselves against disease causing pathogens.

The work led by Dr. Jurriaan Ton and Dr. Estrella Luna at the University of Sheffield in the UK and including scientists from The University of Western Australia, the University Jaume I in Spain and Utrecht University in The Netherlands, has been published in the international journal Nature Chemical Biology.
The scientists identified the key receptor binding a chemical called BABA (β-aminobutyric acid), which is boosting plant immunity.
BABA has long been known for its protective effects against devastating plant diseases, such as potato blight, but has so far not widely been used in crop protection because of undesirable side effects.
“We have found that the plant receptor binding BABA is an ‘aspartyl tRNA synthetase’ which we have called IBI1. This class of enzymes play a vital role in primary metabolism of all cells, but had never been linked to immune responses in plants. Binding of the chemical to this protein triggers a secondary function that ‘primes’ the plant immune system against future attacks by pests and diseases,” Dr Luna said.
Dr Oliver Berkowitz, a Research Associate in the ARC Centre for Excellence in Plant Energy Biology and the School of Plant Biology at UWA was also involved in the research.
“Importantly, our study also revealed that the undesirable side effect of this vaccination, a reduction in growth, can be uncoupled from the beneficial immune reaction,” Dr Berkowitz said.
“Since plant immunisation by BABA is long-lasting, primed crops would require fewer applications of fungicides, thereby increasing sustainability of crop protection. Furthermore, immune priming boosts so-called ‘multi-genic’ resistance in plants. Plant immunity that is controlled by a single resistance gene, on which most conventional breeding programs are based, is comparably easy to overcome by a pathogen. By contrast, priming of multi-genic immunity by BABA is difficult to break, thus offering more durable crop protection,” Dr Ton said.
Although their research has been performed in a weed called ‘Arabidopsis thaliana’, the work horse of plant geneticists, the team is confident that their discovery can be used for the protection of crops from their enemies. Proof-of-concept experiments have already shown that BABA is detected in a similar manner by tomato.
Explore further: Til’ death do us part – in the plant world
More information: Plant perception of β-aminobutyric acid is mediated by an aspartyl-tRNA synthetase, Estrella Luna, Marieke van Hulten, Yuhua Zhang, Oliver Berkowitz, Ana López, Pierre Pétriacq, Matthew A Sellwood, Beining Chen, Mike Burrell, Allison van de Meene, Corné M J Pieterse, Victor Flors & Jurriaan Ton, Published online: 28 April 2014, DOI: 10.1038/nchembio.1520
Journal reference: Nature Chemical Biology
Provided by University of Western Australia

Read more at: http://phys.org/news/2014-04-green-vaccination-boosting-immunity-side.html#jCp

 

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Press Release

Farming for Improved Ecosystem Services Seen as Economically Feasible
April 2014

http://www.aibs.org/bioscience-press-releases/140407_farming_for_improved_ecosystem_services_seen_as_economically_feasible.html

Read this article
By changing row-crop management practices in economically and environmentally stable ways, US farms could contribute to improved water quality, biological diversity, pest suppression, and soil fertility while helping to stabilize the climate, according to an article in the May issue of BioScience. The article, based on research conducted over 25 years at the Kellogg Biological Station in southwest Michigan, further reports that Midwest farmers, especially those with large farms, appear willing to change their farming practices to provide these ecosystem services in exchange for payments. And a previously published survey showed that citizens are willing to make such payments for environmental services such as cleaner lakes.

The article is by G. Philip Robertson and six coauthors associated with the Kellogg Biological Station, which is part of the Long Term Ecological Research Network. The research analyzed by Robertson and colleagues investigated the yields and the environmental benefits achievable by growing corn, soybean, and winter wheat under regimes that use one third of the usual amount of fertilizer—or none at all—with “cover crops” fertilizing the fields in winter. The research also examined “no-till” techniques. The regime that used fewer chemicals resulted in more than 50 percent reductions in the amount of nitrogen that escaped into groundwater and rivers, with crop yields close to those of standard management. Nitrogen pollution is a major problem in inland waterways and coastal regions, where it contributes to the formation of “dead zones.”

The no-till and reduced chemical regimes also mitigated greenhouse warming by taking up greenhouse gases from the atmosphere, in contrast to standard management, which produces significant greenhouse warming by emitting nitrous oxide. The zero-chemical regime mitigated greenhouse warming enough to compensate for the emissions produced under standard management. All three regimes also led to more fertile soil compared with conventional management.

The environmentally improved farming practices that Robertson and his colleagues studied are more complex than conventional ones. But the authors found that although sustained profitability is generally farmers’ overriding concern, substantial proportions would accept payments to adopt such practices, especially those with large farms. And a 2009 survey in Michigan found that members of the public indicated they were willing to pay higher taxes so that land managers could participate in stewardship programs to benefit lakes; a smaller number were willing to pay for a reduction in greenhouse gas emissions.

Robertson and his colleagues argue that in coming decades, human population and income growth will drive agriculture to ever-higher intensities. The danger is that it will become more vulnerable to climate extremes and pest outbreaks. “Now is the time to guide this intensification in a way that enhances the delivery of ecosystems services that are not currently marketed,” they conclude.

This Overview and other articles in the May 2014 issue of BioScience are now published online as Advance Access at http://bioscience.oxfordjournals.org/content/early/recent .

BioScience is published monthly by Oxford Journals. Follow BioScience on Twitter @BioScienceAIBS.

Oxford Journals is a division of Oxford University Press. Oxford Journals publishes well over 300 academic and research journals covering a broad range of subject areas, two-thirds of which are published in collaboration with learned societies and other international organizations. The division been publishing journals for more than a century, and as part of the world’s oldest and largest university press, has more than 500 years of publishing expertise behind it. Follow Oxford Journals on Twitter @OxfordJournals

Jennifer Williams
Production Coordinator, BioScience

American Insitute of Biological Sciences (AIBS)
1900 Campus Commons Drive, Suite 200
Reston, VA 20191
703-674-2500 x209
jwilliams@aibs.org
http://www.aibs.org

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Yao-Hua Law

 

Speed read
Introduced Philidris ants cut cacao tree yields by aiding a pathogen’s spread

But trees with native ants had greater yields than those without any ants

Farmers who manage ant communities are also managing pests, says expert

 

[KUALA LUMPUR] Native ants living in cacao trees in Indonesia that are often seen as pests in fact seem to boost their yields, a study suggests.

Scientists from Germany, Indonesia and Sweden studying how ant communities affect cocoa yields in Sulawesi found that trees with abundant native ants (Dolichoderus sp.) produced the best yields. In contrast, the yields of cacao trees where ants were excluded were 27 per cent lower and those in which an invasive, foreign ant species (Philidris sp.) were introduced had yields that were 34 per cent lower, the study says.

The results were published last week (4 December) in Proceedings of the Royal Society B.
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“Farmers face many challenges and those who manage ant communities are also managing pests.”

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Stacy Philpott, University of California Arno Wielgoss, a graduate researcher from the University of Göttingen, Germany, and the lead scientist of the 16-month study, tells SciDev.Net that ants live in a mutualistic partnership with the mealybugs — insects that suck plant nutrients and excrete sugar to their guardian ants. But they also protect the cocoa pods from even more destructive pests such as cocoa pod borers and Helopeltis bugs.

The invasive Philidris ants transmit the fungus-like plant pathogen Phytophthora sp. and so the heaviest yield loss, according to the study. These ants collect pieces of Phytophthora-infected cocoa pods to build protective tents over the mealy bugs, it says. The study says that Philidris ants and their tent materials harbour infectious Phytophthora spores with which the ants contaminate fresh cocoa pods.

Indonesia is the world’s third biggest cocoa producer. But increased pest attacks and aging trees have slashed its production this year.

Worldwide, cocoa farmers struggle against severe but geographically limited pest infestations. Ants, which form part of the complex network of life in cocoa farms, are often seen as pests.

Farmers often dislike ants, says Stacy Philpott, an associate professor in agroecology at the University of California, Santa Cruz, who studies insects in another tree crop, coffee. She says that the study is important in advancing the understanding of the ecological roles that ants play.

Wielgoss warns that insecticide spraying could hasten Philidris dominance as “insecticides harm other ant species more than Philidris that are protected in their tents”. The spread of Philidris, he adds, would also be likely to aggravate Phytophthora infection.

Despite this, the effects of having Dolichoderus ants may vary, as a Malaysian Cocoa Board officer says that untreated cacao trees produce only half the yields of trees with ant treatment.

Philpott says: “Translating scientific results into practice can be difficult despite vigorous research. Farmers face many challenges and farmers who manage ant communities are also managing pests.”

This article has been produced by SciDev.Net’s South-East Asia & Pacific desk.

Link to abstract in Proceedings of the Royal Society
References
Proceedings of the Royal Society B doi: 10.1098/rspb.2013.2144 (2013)

http://www.scidev.net/global/agriculture/news/native-ants-help-indonesian-cocoa-yields-1.html

 

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Flickr/Bill and Melinda Gates Foundation

 

There was one unpleasant surprise in what was otherwise an invigorating and useful high-level discussion at the EU-Africa Business Forum this week (1 April) in Brussels, Belgium: a skewed focus on success and perhaps a reluctance to admit to failure.

The session was organised to draw up a set of core messages on how to get the business sector and public research organisations to work closer and better together on ensuring food security in Africa and Europe.

These were then fed into 4th EU-Africa Summit of Heads of State and Government of the European Union and African Union also taking place this week (2-3 April) in Brussels.

Following several ‘taster’ presentations that helped set the scene with successful examples, my task was to moderate a discussion that would identify both what works and what doesn’t work in making the two sectors more responsive to each other’s needs.
“It is time to look honestly and constructively at failures in the way we do things — in agricultural research and beyond.”

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Mićo Tatalović
“But despite a lively discussion involving most of the 50 or so delegates, and despite repeated calls to also hear examples of what worked less well, or not at all, we mostly only heard examples of success or thoughts on what ought to happen next.”

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Even a delegate who was involved in setting up a repository of examples of best practice aimed at farmers, when asked if we should also have a repository of ‘worst practice’ — things to definitely avoid, seemed unprepared for the question and unsure of how to answer it.

As in science, where in general only results that show something working well get reported, it seems that the participants preferred to highlight things that have worked well. From the launch of new small and medium size enterprises following on from EU Framework Programme 7’s research project in Egypt, to finding an innovative use for unpopular but productive mushroom farming in Rwanda, the success stories are many.

But as in science, our perspective and understanding are skewed if we never see the rest of the iceberg — the hypotheses that did not turn out to be correct — and don’t investigate why that was.

That things don’t always work the way we intended them to is evident from the various suggestions for new and different initiatives, such as innovative ways of financing agricultural research between the public and private sectors. If everything done so far was a success, why bother changing things — why not repeat past successes?

This lack of examples of less-successful initiatives limits our opportunity for learning.

Indeed, while it may be difficult to own up to having worked on project that just did not deliver, without recognising failure and understanding why it happened, we are unlikely to avoid it in future.

This is why SciDev.Net’s news recently started looking more proactively at past initiatives originally launched with high acclaim and high expectations, only to slowly fade from the media spotlight. These follow-up stories (‘whatever happened to…?’) offer valuable insights for others to learn from.

Recent examples include a 2008 MalariaEngage website designed to find a new way to crowdsource finding for malaria research in Africa; and Science for Humanity, which attempted to link up scientists and NGOs for better adoption of research in development work.

It is time to look honestly and constructively at failures in the way we do things — in agricultural research and beyond.

http://www.scidev.net/global/innovation/scidev-net-at-large/eu-africa-research-must-start-learning-from-failures.html

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