̽��ֱ�� of Cambridge - Rothamsted Research

Virus attracts bumblebees to infected plants by changing scent

fpjl2 — Thu, 11 Aug 2016 18:05:25 +0000

Plant scientists at the ̽��ֱ�� of Cambridge have found that the cucumber mosaic virus (CMV) alters gene expression in the tomato plants it infects, causing changes to air-borne chemicals – the scent – emitted by the plants. Bees can smell these subtle changes, and glasshouse experiments have shown that bumblebees prefer infected plants over healthy ones.

Scientists say that by indirectly manipulating bee behaviour to improve pollination of infected plants by changing their scent, the virus is effectively paying its host back. This may also benefit the virus: helping to spread the pollen of plants susceptible to infection and, in doing so, inhibiting the chance of virus-resistant plant strains emerging.

̽��ֱ��authors of the new study, published today in the journal PLOS Pathogens, say that understanding the smells that attract bees, and reproducing these artificially by using similar chemical blends, may enable growers to protect or even enhance yields of bee-pollinated crops.

“Bees provide a vital pollination service in the production of three-quarters of the world’s food crops. With their numbers in rapid decline, scientists have been searching for ways to harness pollinator power to boost agricultural yields,” said study principal investigator Dr John Carr, Head of Cambridge’s Virology and Molecular Plant Pathology group.

“Better understanding the natural chemicals that attract bees could provide ways of enhancing pollination, and attracting bees to good sources of pollen and nectar – which they need for survival,” Carr said.

He conducted the study with Professor Beverley Glover, Director of Cambridge ̽��ֱ�� Botanic Garden, where many of the experiments took place, and collaborators at Rothamsted Research.

CMV is transmitted by aphids – bees don’t carry the virus. It’s one of the most prevalent pathogens affecting tomato plants, resulting in small plants with poor-tasting fruits that can cause serious losses to cultivated crops.

Not only is CMV one of the most damaging viruses for horticultural crops, but it also persists in wild plant populations, and Carr says the new findings may explain why:

“We were surprised that bees liked the smell of the plants infected with the virus – it made no sense. You’d think the pollinators would prefer a healthy plant. However, modelling suggested that if pollinators were biased towards diseased plants in the wild, this could short-circuit natural selection for disease resistance,” he said.

“ ̽��ֱ��virus is rewarding disease-susceptible plants, and at the same time producing new hosts it can infect to prevent itself from going extinct. An example, perhaps, of what’s known as symbiotic mutualism.”

̽��ֱ��increased pollination from bees may also compensate for a decreased yield of seeds in the smaller fruits of virus-infected plants, say the scientists.

̽��ֱ��findings also reveal a new level of complexity in the evolutionary ‘arms race’ between plants and viruses, in which it is classically believed that plants continually evolve new forms of disease-resistance while viruses evolve new ways to evade it.

“We would expect the plants susceptible to disease to suffer, but in making them more attractive to pollinators the virus gives these plants an advantage. Our results suggest that the picture of a plant-pathogen arms race is more complex than previously thought, and in some cases we should think of viruses in a more positive way,” said Carr.

Plants emit ‘volatiles’, air-borne organic chemical compounds involved in scent, to attract pollinators and repulse plant-eating animals and microbes. Humans have used them for thousands of years as perfumes and spices.

̽��ֱ��researchers grew plants in individual containers, and collected air with emissions from CMV-infected plants, as well as ‘mock-infected’ control plants.

Through mass spectrometry, researchers could see the change in emissions induced by the virus. They also found that bumblebees could smell the changes. Released one by one in a small ‘flight arena’ in the Botanic Gardens, and timed with a stopwatch by researchers, the bees consistently headed to the infected plants first, and spent longer at those plants.

“Bees are far more sensitive to the blends of volatiles emitted by plants and can detect very subtle differences in the mix of chemicals. In fact, they can even be trained to detect traces of chemicals emitted by synthetic substances, including explosives and drugs,” said Carr.

Analysis revealed that the virus produces a factor called 2b, which reprograms genetic expression in the tomato plants and causes the change in scent.

Mathematical modelling by plant disease epidemiologist Dr Nik Cunniffe, also in the Department of Plant Sciences at Cambridge, explored how the experimental findings apply outside the glasshouse. ̽��ֱ��model showed how pollinator bias for infected plants can cause genes for disease-susceptibility to persist in plant populations over extremely large numbers of generations.

̽��ֱ��latest study is the culmination of work spanning almost eight years (and multiple bee stings). ̽��ֱ��findings will form the basis of a new collaboration with the Royal Horticultural Society, in which they aim to increase pollinator services for cultivated crops.

With the global population estimated to reach nine billion people by 2050, producing enough food will be one of this century’s greatest challenges. Carr, Glover and Cunniffe are all members of the Cambridge Global Food Security Initiative at Cambridge, which is involved in addressing the issues surrounding food security at local, national and international scales.

̽��ֱ��use of state-of-the-art experimental glasshouses at Cambridge Botanic Garden, and equipment at Cambridge and Rothamsted, was funded by the Leverhulme Trust.

Study of bee-manipulating plant virus reveals a “short-circuiting” of natural selection. Researchers suggest that replicating the scent caused by infection could encourage declining bee populations to pollinate crops – helping both bee and human food supplies.

Modelling suggested that if pollinators were biased towards diseased plants in the wild, this could short-circuit natural selection for disease resistance

John Carr

John Carr/Alex Murphy

Researcher Sanjie Jiang inside the 'flight arena' in the glasshouse of the Cambridge ̽��ֱ�� Botanic Garden.

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes

Cambridge leads UK institutions in agreement on crop science with Indian government

ts657 — Wed, 24 Feb 2016 17:06:24 +0000

India’s Department of Biotechnology and a consortium of British research institutions, led by the ̽��ֱ�� of Cambridge, signed a Memorandum of Understanding yesterday at the Ministry of Earth Sciences in New Delhi for the establishment of a joint UK-India crop science programme.

̽��ֱ��aim of the agreement is to enhance collaborative research, promote knowledge exchange, and support capacity building to develop resilience in food security.

̽��ֱ��agreement was signed on behalf of the ̽��ֱ�� of Cambridge by the Vice-Chancellor Professor Leszek Borysiewicz, Professor Krishnaswamy VijayRaghavan of India’s Ministry of Science and Technology, and Director of the Research Councils UK India Dr Nafees Meah, on behalf of the Biotechnology and Biological Sciences Research Council (BBSRC).

It was also signed by representatives from NIAB in Cambridge; the John Innes Centre and the ̽��ֱ�� of East Anglia, in Norwich and Rothamsted Research.

Professor Leszek Borysiewicz said: “This collaboration builds on the close links already established between leading researchers in the United Kingdom and India and is another great example of both countries’ commitment to growing our partnerships in translational and applied research.

“This collaboration will create opportunities for leading experts in the UK and India to come together to tackle global challenges in the areas of food security, crop science and biotechnology.”

Professor VijayRaghavan said: “ ̽��ֱ��United Kingdom has been a long-standing partner with the Government of India in Science and Technology, a collaboration that has grown from strength to strength.

“On the foundation of this excellence we are delighted to take a very new and very important direction in crop science. Our partners are the best in the UK and together we can be the best anywhere, working together to address a key global problem.”

Dr Tina Barsby, CEO and Director of NIAB, said: “We are delighted to be part of this international collaboration to develop and improve the translation of fundamental crop research into agronomic practice.

“We want to give farmers and growers throughout the sub-continent access to the most advanced developments in agricultural science and technology; essential for them to meet the challenges of growing crops in the face of changing climatic conditions and increasing food security demands.”

All parties agreed on the importance of crop science as an area of enormous potential for scientific collaboration, and its central role in driving global food security in India and beyond.

̽��ֱ��agreement foresees joint projects focusing on the fundamental science underpinning yield enhancement, disease resistance and drought resistance; research into crop re-breeding; and the translation of fundamental research into sustainable agriculture practice.

It also contemplates the establishment of a joint Indo-UK Plant Science Centre in India.

A collaboration between leading scientists in the UK and India will focus on tackling global food shortages with research into increasing crop yields and improving disease and drought resistance.

This collaboration will create opportunities for leading experts in the UK and India to come together to tackle global challenges in the areas of food security, crop science and biotechnology.

Vice-Chancellor Professor Leszek Borysiewicz

ICRISAT

Pearl millet

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes

Boosting farm yields to restore habitats could create greenhouse gas ‘sink’

fpjl2 — Mon, 04 Jan 2016 15:57:07 +0000

New research into the potential for sparing land from food production to balance greenhouse gas emissions has shown that emissions from the UK farming industry could be largely offset by 2050. This could be achieved if the UK increased agricultural yields and coupled this with expanding the areas of natural forests and wetlands to match its European neighbours.

̽��ֱ��new study suggests that by upping forest cover from 12% to 30% of UK land over the next 35 years – close to that of France and Germany, but still less than the European average – and restoring 700,000 hectares of wet peatland, these habitats would act as a carbon ‘sink’: sucking in and storing carbon.

This could be enough to meet government targets of 80% greenhouse gas reduction by 2050 for the farming industry. Agriculture currently produces around 10% of all the UK’s damaging greenhouse gas emissions.

̽��ֱ��new woodlands and wetlands would be more than just a carbon sink, say researchers. They would help support declining UK wildlife – including many species of conservation concern – provide more areas for nature recreation, and help to reduce flooding.

However, to make space for habitat restoration, and to meet rising levels of food demand, land sparing would depend on increases in farm yields, so that food needs can be met from less farmland.

̽��ֱ��new study, published today in the journal Nature Climate Change, is the first to show that land sparing has the technical potential to significantly reduce greenhouse gas emissions at a national scale.

“Land is a source of greenhouse gases if it is used to farm fertiliser-hungry crops or methane-producing cattle, or it can be a sink for greenhouse gases – through sequestration. If we increase woodland and wetland, those lands will be storing carbon in trees, photosynthesising it in reeds, and shunting it down into soils,” said senior author Prof Andrew Balmford, from Cambridge ̽��ֱ��’s Department of Zoology.

“We estimate that by actively increasing farm yields, the UK can reduce the amount of land that is a source of greenhouse gases, increase the ‘sink’, and sequester enough carbon to hit national emission reduction targets for the agriculture industry by 2050,” he said.

̽��ֱ��study originated from a workshop run as part of the new Cambridge Conservation Initiative, which convened leading experts and asked them to “look into their crystal balls”, says Balmford. “We wanted to know what food yield increases they reckoned were achievable in the 2050 timescale across crop and livestock sectors,” he said.

This included researchers from the Universities of California, Bangor, Aberdeen, East Anglia, the Royal Society for the Protection of Birds, Forestry Commission, Rothamsted Research, ADAS UK Ltd and Scotland’s Rural College (SRUC).

̽��ֱ��potential they identified included improving farm management and optimising breeding programmes to produce plants that are better at capturing soil nutrients, sunlight and water, and to produce more efficient animals that produce less methane.

̽��ֱ��researchers then used these and other data to produce a series of modelled scenarios that projected long-term farm yields. Scenarios ranged from yield declines through to sustained yield growth that averaged 1.3% per year until 2050.

If yields rise, the area of farmland required for food production can decline – allowing countryside to be spared. By converting spared land back to natural habitats of woodland and wetland, which would have been a large portion of the UK’s native land cover in the past, a carbon sink is created that the research suggests could come close to cancelling out agricultural emissions in just a few decades.

Dr Toby Bruce, co-author from Rothamsted Research, said: " ̽��ֱ��current findings show the value of land sparing for reducing greenhouse gases. To allow this productivity needs to increase on the remaining land, for example, by minimising crop losses to pests, weeds and diseases or by improving crop nutrition.”

Importantly, says Balmford, the research team did not allow themselves the “get-out-of-jail-free card” of increasing food imports. Overall food consumption looks set to rise substantially – some 38% – in the UK by 2050, and the researchers locked into their future models the contribution that UK production makes to its food supply.

“We made sure we met expected production requirements in all our figures, and then explored the consequences of different ways of achieving them,” he said.

However, it is not all or nothing, say the researchers, who conducted lots of sensitivity analyses around different ways of using spared land, and different levels of yield growth, consumer waste, and meat consumption – which has a disproportionate environmental footprint

“Reducing meat consumption appears to offer greater mitigation potential than reducing food waste, but more importantly, our results highlight the benefits of combining measures,” said Balmford.

“For example, coupling even moderate yield growth with land sparing and reductions in meat consumption has the technical potential to surpass an 80% reduction in net emissions,” he said.

Added Balmford: “We need to turn our minds to figuring out policy mechanisms that can deliver sustainable high yield farming that doesn’t come at the expense of animal welfare, soil and water quality, as well as safeguarding and restoring habitats.

“ ̽��ֱ��right incentives need to be provided to landowners to spare land. Subsidies under the EU’s Common Agricultural Policy could be redirected so that landowners get paid properly for taking land out of food production and putting it into climate regulation.

“If we are serious about saving the planet for anything more than food production then the focus has to be on increasing yields and sparing land for the climate. We need to look objectively and dispassionately at every option we have for achieving that.”

New study using UK data is first to show that raising farm yields and allowing ‘spared’ land to be reclaimed for woodlands and wetlands could offset greenhouse gas produced by farming industry to meet national target of 80% emissions reduction by 2050.

Land is a source of greenhouse gases if it is used to farm fertiliser-hungry crops or methane-producing cattle, or it can be a sink for greenhouse gases – through sequestration

Andrew Balmford

SwaloPhoto

Rural Landscape near Fife

̽��ֱ��text in this work is licensed under a Creative Commons Attribution 4.0 International License. For image use please see separate credits above.

Yes

Licence type:

Attribution-Noncommerical

Plant scientists call for rethink of GM crop regulation

jfp40 — Wed, 19 Mar 2014 11:50:22 +0000

In a report to the Council for Science and Technology, which advises the Prime Minister on science policy, the scientists warn that unless GM crops are regulated at national, rather than at EU level, European agriculture could suffer because it will be unable to adopt GM crops.

̽��ֱ��new regulatory system should be modelled on the way pharmaceuticals are licensed in the UK, says the report, which was written by scientists at the universities of Cambridge and Reading, ̽��ֱ��Sainsbury Laboratory and Rothamsted Research.

According to lead author Professor Sir David Baulcombe of the Department of Plant Sciences at Cambridge: “Most concerns about GM crops have nothing to do with the technology, which is as safe as conventional breeding.

“They are more often related to the way that the technology is applied and whether it is beneficial for small scale farmers or for the environment. To address these concerns we need to have an evidence-based regulatory process that focuses on traits, independent of the technology that has been used to develop them.”

This is the approach used for regulating pharmaceuticals, regulators looking at the effects that new drugs have on patients, not at the technology used to develop them – which in many cases involves genetic modification.

̽��ֱ��report recommends the European Food Safety Authority retains an advisory role on risk and safety, similar to the European Medicines Agency for pharmaceuticals, but that approval is made on a national basis, as by the National Institute for Clinical Excellence in the UK.

“As there is no evidence for intrinsic environmental or toxicity risks associated with GM crops, it is not appropriate to have a regulatory framework that is based on the premise that GM crops are more hazardous than crop varieties produced by conventional plant breeding,” it says.

Since GM crops were first developed 30 years ago, major advances in basic science have led to new methods for transferring genes into specific locations in a crop plant's genome.

To respond to today's challenges of population growth, climate change and environmental degradation, as well as the need to develop biofuels and other materials, the report argues plant breeders in the UK – which is a world leader in plant genomics – need GM technology and a well-functioning R&D pipeline for both GM and non-GM crop varieties.

GM crops were first grown commercially in the USA in 1994, and in Europe in 1998. They are now grown in 28 countries worldwide, with GM crops currently accounting for 12% of global arable acreage. Most of that acreage is soybean and cotton, and 81% of the global acreage of these crops is sown to GM varieties.

However, even though 70% of protein fed to livestock in the European Union is imported as GM crop products, less than 0.1% of the global acreage of GM crops is cultivated in Europe. This, the report argues, is because experimentation and commercial release of GM crops in the EU is subject to much more stringent regulation than conventionally bred plants, with a slow and inefficient approval process.

As a result, multinational companies such as BASF and Monsanto have abandoned research to develop GM crops in Europe, and there has been a significant reduction in experimental field trials in the UK, with only one in 2012, compared with 37 in 1995.

To ensure a well-functioning research and development pipeline that can translate genomic research from the laboratory to the market place, the report also recommends establishing a new R&D capacity – PubGM.

PubGM would allow preliminary evaluation of the practical application of academic research findings to crops, including field testing new GM crops either in partnership with companies or so that the public sector could validate traits before engaging in partnerships with the private sector.

Leading plant scientists have called for major changes to the way GM crops are licensed.

Most concerns about GM crops have nothing to do with the technology, which is as safe as conventional breeding.

Professor Sir David Baulcombe

Jesper Dyhre Nielsen

Field and sky

This work is licensed under a Creative Commons Licence. If you use this content on your site please link back to this page.

Yes

Licence type:

Attribution-Noncommercial-ShareAlike