NEWS

FUTURE WHEAT HARVESTS VERY VULNERABLE TO DISEASE, WARN EXPERTS

Within two years a virus outbreak will likely hit European yields, leading to a hike in food prices across the continent.

  • 16
  • NOV
  • 2018

More than 100 delegates from the UK’s governmental, scientific, industrial and farming sectors will gather at Rothamsted today to discuss how a forthcoming EU insecticide ban will leave the crop open to attack from aphids that spread Barley Yellow Dwarf Virus, or BYDV.

Existing analyses suggest UK wheat yields would decrease by the equivalent of 4½ million loaves of bread a day because of the ban.

Lower yields could become a regular feature, as a disease-resistant wheat variety could be more than a decade away, says Dr Kim Hammond-Kosack, conference organiser and a senior plant pathologist at Rothamsted Research.

“Our scientists predict that in February and March 2020 farmers, will be looking out on virus infected, yellowing fields of winter wheat, and consequently later that year consumers will be buying and eating more expensive food stuffs made using wheat imports from Canada, America, and the Ukraine.”

“With few options to control these aphids, next year could be the last good year for European wheat harvests for some considerable time.

“Currently no one has tested the UK’s recommended wheat varieties for their resistance to BYDV. Resistance to the virus has not been a breeding target for years because of the availability of effective insecticides. Given it takes seven or eight years to breed a new crop variety, and then two or three years of official testing before a variety can make it on the recommended list, you can see time is against us.” 

Dr Gia Aradottir, an insect specialist at Rothamsted said until the responses of recommended wheat varieties to the virus are correctly determined “the wheat breeding industry will not know the true scale of the problem facing them.”

The threat of disease has arisen because of a EU-wide ban on the neonicotinoid insecticide currently used to control the aphids that spread BYDV.

The insects can still be controlled by a different class of insecticides called pyrethroids, but there is already a resistance mutation present in one of the species, the grain aphid, to these chemicals.

Analogous to anti-biotic resistance that arises in many human diseases, insect populations can also develop a resistance to insecticides if they are over used.

“With the ban on the neonicotinoids, there is likely to be an increased use of pyrethroids which could hasten the development of this resistance, and could also select for insecticide resistance in the bird-cherry aphid, the other aphid species that spreads BYDV,” says Dr Aradottir.

“If we have another autumn of high aphid numbers next year, followed by a mild winter, then the outlook for wheat harvests in 2020 could be very bleak indeed.”

Wheat is arguably the world’s most important crop, providing a fifth of our calories. Its genome – which is five times bigger than ours - was finally decoded earlier this year by an international consortium of scientists, including researchers from Rothamsted.

In the absence of a disease resistant wheat variety arising from classical crop breeding methods, gene modified or gene edited crops might produce an answer – but the growing of such crops is also currently banned in the EU.

Another route might be the development of a new insecticide, or a reversal on the current noenicitinoid ban. Neonics, as they are commonly known, have been outlawed in the EU because of growing concerns over their impact on bee populations.

At today’s Wheat Genetic Improvement Network (WGIN) conference, a panel of experts will address this loss of pesticide control, and Rothamsted, along with its collaborators, are already urgently working on solutions.

They have already planted various wheat varieties without applying the insecticide to determine the likely impact of the ban on 2020’s harvests.

The Institute also has a study population of aphids infected with BYDV to test for resistance in common, old and wild wheat varieties.

And they have also recently developed a more sensitive diagnostic test to determine whether any commercial wheat varieties possess even a small amount of resistance that could be exploited by plant breeders.

“We already have a good breadth of expertise within the Institute to tackle this problem from all the important angles, including monitoring, diagnostics, aphid resistance, insecticide resistance and modelling,” said Dr Hammond-Kosack.  

1)      The Wheat Genetic Improvement Network (WGIN) started in 2003 to provide genetic and molecular resources for research in other Defra projects and for a wide range of wheat research projects in the UK. The resources under development include wheat genetic stocks, mapping populations, molecular markers and marker technologies, trait identification and evaluation, genomics and bioinformatics. The funded partners in WGIN phase 4 are Rothamsted Research and the John Innes Centre.

2)      The WGIN 16th Stakeholder Meeting 16th November 2018, held at Rothamsted Research will be attended by over 100 delegates from, amongst others, Defra, BBSRC, ADHB, HGCA, and UK based commercial wheat breeding companies as well as crop consultants, farm managers and farmers.

3)      Discussion panel: Alan Dewar (Independent Crop Protection Consultant), Neil Paveley (Director - Crop Protection, ADAS), David Feuerhelm (Wheat Breeder, Syngenta), Keith Norman (Independent Consultant, former Technical Director of Velcourt), Russell McKenzie (Farmer, Member of AHDB Monitoring Farms Programme), Rosie Bryson BASF & Peter Shewry (chair) RRes

4)      NFU figures: UK wheat yields would decrease by at least 0.6 tonnes per hectare– the equivalent of 1 million tonnes of wheat per year or 4½ million loaves of bread lost every day.  https://www.nfuonline.com/save-our-seed-treatments-a5-online/

5)      BYDV affects all cereals and grasses. The initial symptoms of BYDV infection are normally seen as individual plants scattered through the crop with bright yellow upper leaves. Later, as infection spreads, larger areas of the crop become infected appearing as patches of bright yellow and severely stunted plants. BYDV has increased in importance in many areas of the UK. The frequency of very mild winters means that, for many farms, BYDV is now a regular problem. Early infections can kill patches of plants potentially resulting in large yield losses. https://cereals.ahdb.org.uk/cereal-disease-encyclopedia/diseases/barley-yellow-dwarf-virus-(bydv).aspx

About Rothamsted Research
Rothamsted Research is the longest-running agricultural research institute in the world. We work from gene to field with a proud history of ground-breaking discoveries, from crop treatment to crop protection, from statistical interpretation to soils management. Our founders, in 1843, were the pioneers of modern agriculture, and we are known for our imaginative science and our collaborative influence on fresh thinking and farming practices.
Through independent science and innovation, we make significant contributions to improving agri-food systems in the UK and internationally. In terms of the institute’s economic contribution, the cumulative impact of our work in the UK was calculated to exceed £3000 million a year in 20151. Our strength lies in our systems approach, which combines science and strategic research, interdisciplinary teams and partnerships.
Rothamsted is also home to three unique resources. These National Capabilities are open to researchers from all over the world: The Long-Term Experiments, Rothamsted Insect Survey and the North Wyke Farm Platform.
We are strategically funded by the Biotechnology and Biological Sciences Research Council (BBSRC), with additional support from other national and international funding streams, and from industry. We are also supported by the Lawes Agricultural Trust (LAT).
For more information, visit https://www.rothamsted.ac.uk/; Twitter @Rothamsted
1Rothamsted Research and the Value of Excellence: A synthesis of the available evidence, by Séan Rickard (Oct 2015)

About BBSRC
The Biotechnology and Biological Sciences Research Council is part of UK Research and Innovation, a non-departmental public body funded by a grant-in-aid from the UK government.
BBSRC invests in world-class bioscience research and training on behalf of the UK public. Our aim is to further scientific knowledge, to promote economic growth, wealth and job creation and to improve quality of life in the UK and beyond.
Funded by government, BBSRC invested £469 million in world-class bioscience in 2016-17. We support research and training in universities and strategically funded institutes. BBSRC research and the people we fund are helping society to meet major challenges, including food security, green energy and healthier, longer lives. Our investments underpin important UK economic sectors, such as farming, food, industrial biotechnology and pharmaceuticals.
More information about BBSRC, our science and our impact.
More information about BBSRC strategically funded institutes

About LAT
The Lawes Agricultural Trust, established in 1889 by Sir John Bennet Lawes, supports Rothamsted Research’s national and international agricultural science through the provision of land, facilities and funding. LAT, a charitable trust, owns the estates at Harpenden and Broom's Barn, including many of the buildings used by Rothamsted Research. LAT provides an annual research grant to the Director, accommodation for nearly 200 people, and support for fellowships for young scientists from developing countries. LAT also makes capital grants to help modernise facilities at Rothamsted, or invests in new buildings.