Corporate Banner
Satellite Banner
Technology
Networks
Scientific Communities
 
Become a Member | Sign in
Home>News>This Article
  News
Return

New African Cassava Resists Devastating Viruses

Published: Tuesday, October 02, 2012
Last Updated: Tuesday, October 02, 2012
Bookmark and Share
Plant scientists at ETH Zurich have developed a new African cassava preferred by consumers and farmers that is resistant to the two major virus diseases in Africa. Now they want to test the resistant cassava in Africa.

Cassava is one of the most important crops in tropical countries, particularly in Sub-Saharan Africa. However, plant viruses are threatening cassava production and with it the staple food of hundreds of millions of people. Under the leadership of Wilhelm Gruissem, Professor of Plant Biotechnology and his senior scientist Dr. Hervé Vanderschuren, researchers at ETH Zurich have used gene technology to develop a new cassava variety that is resistant to the feared cassava brown streak virus. The virus infects the edible starchy roots and turns them brown, which makes the roots unpalatable for consumers. The virus originated in East Africa and is threatening to spread to Central and West Africa.

Developing immune cassava using small RNAs

In order to make cassava resistant to the brown streak virus, the researchers modified the genetic make-up of one variety of cassava to produce small interfering RNA molecules (siRNA). The plant produces the siRNA naturally after virus infection, but the researchers have now tricked cassava to produce the siRNA in all of its parts before the virus can infect it. As soon as the virus attacks the plant, the short siRNA stops the virus by attaching to the genome of the virus that is also made of RNA. This prevents the virus from multiplying and spreading throughout the plant.

Glasshouse trials have shown that the new gene producing the siRNA protects cassava effectively from the virus. Even several months after infection of the transgenic cassava plants with the brown streak virus, the scientists did not find any evidence that the virus could multiply. The production of the siRNA does not affect cassava itself. It grows normally and produces healthy roots. The researchers targeted a part of the virus RNA genome that has been highly conserved during evolution and thus only very rarely changes. This should make it more difficult for the virus to adapt to the siRNA-mediated immunity.

Resistance to another cassava virus remains

The researchers used the Nigerian TME 7 variety, also known as “Oko-iyawo”. This variety is naturally resistant to cassava mosaic disease, which is caused by another virus that is severely impacting cassava production all of Africa. Prof. Wilhelm Gruissem explains that this resistance is not changed by the new resistance to the brown streak virus. The brown streak virus is most likely transmitted by the same silverleaf whitefly (Latin: Bemisia tabaci) that also spreads cassava mosaic disease. This tiny insect sucks on plant juices, and in doing so transmits the viruses into the cassava plant. The silverleaf whitefly population has hugely increased in recent decades, emphasises Prof. Willhelm Gruissem, and is posing a greater threat than ever to the growth of cassava. He adds that it is difficult to control the whitefly, even if African farmers can afford to buy insecticides. This is why it is much more efficient and more environmentally friendly to protect cassava against viruses using genetic modification.

Preferred variety extended

The ETH Zurich scientists chose TME 7 from dozens of potential varieties because TME 7 is popular among consumers and farmers and has the best prerequisites for successful cultivation. As the next step, Prof. Gruissem and Dr. Vanderschuren, together with colleagues in Africa, want to test if the improved cassava variety in the field remains resistant to both viruses under natural conditions. The Fiat Panis Foundation in Germany, which has supported cassava research at ETH, has already reserved funding for field experiments. The ETH Zurich scientists are also actively engaged in transferring the technology to interested research institutes in Africa to develop virus resistance in local varieties preferred by consumers in their countries.


Further Information

Join For Free

Access to this exclusive content is for Technology Networks Premium members only.

Join Technology Networks Premium for free access to:

  • Exclusive articles
  • Presentations from international conferences
  • Over 3,500+ scientific posters on ePosters
  • More Than 5,000+ scientific videos on LabTube
  • 35 community eNewsletters


Sign In



Forgotten your details? Click Here
If you are not a member you can join here

*Please note: By logging into TechnologyNetworks.com you agree to accept the use of cookies. To find out more about the cookies we use and how to delete them, see our privacy policy.

Related Content

A Peachy Defense System for Seeds
ETH chemists are developing a new coating method to protect seeds from being eaten by insects. In doing so, they have drawn inspiration from the humble peach and a few of its peers.
Tuesday, May 24, 2016
Beta Cells from Love Handles
Using a synthetic genetic program to instruct stem cells taken from fatty tissue to become cells that are almost identical to natural beta cells, researchers are closer to creating a repair kit for diabetes patients.
Tuesday, April 12, 2016
Broccoli May Impact Drug Efficacy
Scientists discover link between broccoli component and improved drug efficacy.
Wednesday, March 16, 2016
Genes for a Longer, Healthier Life Found
Out of a 'haystack' of 40,000 genes from three different organisms, scientists at ETH Zurich and a research consortium in Jena have found genes that are involved in physical ageing.
Wednesday, December 02, 2015
Increasing Vitamin D Supplementation
New study from ETH Zurich finds that elderly women should consume more vitamin D than previously recommended during the winter months.
Tuesday, November 03, 2015
Bumblebee Genome Mapped
A research collaboration spearheaded by ETH Zurich has shed light on the genome of two commercially important species of bumblebees. The findings provide unexpected insights into the ecology and evolution of bumblebees and honeybees.
Thursday, April 30, 2015
Controlling Genes with Your Thoughts
Researchers develop the first gene network to be operated via brainwaves.
Tuesday, November 11, 2014
New Defence Mechanism Against Viruses Discovered
Mechanism may represent one of the oldest defence mechanisms against viruses in evolutionary history.
Friday, September 12, 2014
Protecting Olive Oil from Counterfeiters
Using magnetic DNA particles, ETH Zurich researchers have shown how olive oil can be tagged to prevent counterfeiting.
Friday, April 25, 2014
Swiss researchers develop rice with increased (six-fold!) iron content
Scientists at ETH Zurich have developed rice plants that contain six times more iron in polished rice kernels.
Thursday, August 20, 2009
Scientific News
Mass Spec Technology Drives Innovation Across the Biopharma Workflow
With greater resolving power, analytical speed, and accuracy, new mass spectrometry technology and techniques are infiltrating the biopharmaceuticals workflow.
One Step Closer to Precision Medicine for Chronic Lung Disease Sufferers
A study led by University of North Carolina at Chapel Hill, and National Jewish Health, has provided evidence of links between SNPs and known COPD blood protein biomarkers.
Gene Regulation in Brain May Explain Repetitive Behaviors in Rett Syndrome Patients
The research could be a key step in developing treatments to eliminate symptoms that drastically impair the quality of life in Rett patients.
Heart Arrhythmia Caused by Mosaic of Mutant Cells
Researchers have solved the genetic mystery of an infant suffering from heart arrhythmia.
Iron Nanoparticles Make Immune Cells Attack Cancer
Researchers accidentally discover that nanoparticles invented for anemia treatment can trigger the immune system’s ability to destroy tumor cells.
Crispr Toolbox Expanded By Protein
Researchers have shown a newly discovered CRISPR protein has two distinct RNA cutting activities.
CES Score May Predict Response to Cancer Treatment
Researchers identify new type of biomarker that helps predict prognosis and response to several types of cancer treatment.
Uncovering Cancer’s ‘Invisibility Cloak’
Researchers discover cancer cell mechanism to become invisible to the body's immune system.
Genetic Impact of Endurance Training
Research has found that endurance training changes genetic activity in thousands of genes, giving rise to large number of altered RNA variants.
Treating Sepsis with Marine Mitochondria
Mitochondrial alternative oxidase from a marine animal combats bacterial sepsis.
Scroll Up
Scroll Down
Skyscraper Banner

Skyscraper Banner
Go to LabTube
Go to eposters
 
Access to the latest scientific news
Exclusive articles
Upload and share your posters on ePosters
Latest presentations and webinars
View a library of 1,800+ scientific and medical posters
3,500+ scientific and medical posters
A library of 2,500+ scientific videos on LabTube
5,000+ scientific videos
Close
Premium CrownJOIN TECHNOLOGY NETWORKS PREMIUM FOR FREE!