ICARDA News

International Center for Agricultural Research in the Dry Areas

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Phone: (963-21) 2213433, 2213477, 2225112, 2225012
Fax: (963-21) 2213490, 2225105;
E-mail: ICARDA@CGIAR.ORG
Website: www.icarda.cgiar.org
                                 Media contact: Dr Surendra Varma (s.varma@CGIAR.ORG)
 
 
10 November 2005
ICARDA-DPI Collaboration for Viral Disease Diagnosis
in Australia’s Pulse Crops
Dr Safaa Kumari (center) with Australian scientists at the Victorian Department of Primary Industries.
Collaboration between ICARDA and the Victorian Department of Primary Industries (DPI) is helping to accelerate the progress in the detection and diagnosis of viral diseases in pulse crops in Australia. Dr Safaa Kumari, a specialist in virus diagnostics at ICARDA, was on a fellowship program at DPI recently to conduct research and share ICARDA's experience in the diagnosis of viral diseases of pulse crops. During her stay at DPI, she worked with three lead scientists: Dr Brendan Rodoni, Dr Angela Freeman, and Mr Joop van Leur (a pulse specialist at the DPI-NSW, Tamworth, and a former ICARDA scientist).

In a Grains Research and Development Corporation (GRDC) press release, Mr van Leur said: “Exotic and endemic viruses can be a major production constraint, causing heavy losses in pulse crops in Australia. Viruses are a threat to the expanding legume cultivation in the northern grain region. Frequent summer rains provide a climate that is particularly favorable to the survival of both viruses and virus vectors. Completely different viruses can cause symptoms that are indistinguishable in the field. We also need to distinguish single infections from mixed ones, especially as single infections may not cause as much damage as mixed ones. Having access to a fast and cheap but reliable diagnostic tool is crucial. For example, a widespread infection by bean leaf roll virus in northern faba bean fields during 2001 was mistaken for herbicide damage, while this spring, local agronomists diagnosed tomato spotted wilt virus as chocolate spot or root rot.”

Identifying these viruses is sometimes complex, but Dr Kumari’s work has helped to make considerable improvements to an effective diagnostic tool, the tissue blot immunoassays (TBIA). TBIA has proved to be the most appropriate technique for breeding programs and large-scale quantitative surveys. It can be used for samples that cannot be processed immediately. It is also a vital tool in detecting previous unnoticed outbreaks of exotic diseases in samples that are several years old. “Not only did she manage to describe variation in a number of different virus genera, she has also opened a whole new avenue of possibilities to examine old samples by extracting DNA and RNA from TBIA membranes blotted several years ago,” said Dr Rodoni. “We have also managed to compare the genetic make-up of an extremely dangerous exotic virus, faba bean necrotic yellows virus, with that of a related local virus, subterranean clover stunt virus,” he said.

Testing of years-old samples, either by TBIA or by molecular tools has an important biosecurity benefit. Dr Angela Freeman, a Victorian DPI senior plant virologist with grains biosecurity and quarantine roles, said that the TBIA test is crucial in this regard. “If quarantine reports an incursion of a disease, we can pull out our old samples and test them for this disease. Then we can safely say whether it’s an incursion, or this disease has been around for some years but we couldn’t test for it then. It’s extremely valuable and another benefit of TBIA testing,” she said.

Dr Kumari said that the outcomes of her visit to Australia were beyond her expectations. She said: “At Knoxfield, we were able to improve on serological tests for virus diagnosis and to link these with the molecular methods developed by DPI. This has provided a more complete picture of which pulse viruses are present in the field and will greatly improve the accuracy of diagnosis…it has also been an excellent opportunity to develop expertise working with new experienced scientists, diagnostic methods and equipment.”

However, Dr Rodoni and Dr Kumari agreed that many questions remain, which require further research both in Australia and eslewhere. “The answers to these questions would be of considerable benefit to the pulse crop industry,” said Dr Rodoni.

Collaboration between ICARDA's virology laboratory and the Australian pulse research programs focuses on the selection of virus resistance in faba bean and on the identification of pulse viruses–funded by the GRDC through the Northern Faba Bean Improvement Program–and in the survey work in China–funded by the Australian Center for International Agricultural Research (ACIAR) through the China-Australia project on improvement of faba bean and field pea. The new projects might as well open completely new avenues of collaborative research that will benefit both ICARDA and the Australian pulse virology research.

For more information contact: Dr Safaa Kumari

About ICARDA: Established in 1977, ICARDA (www.icarda.cgiar.org) serves the entire developing world for the improvement of barley, lentil, and faba bean; and dry-area developing countries for the on-farm management of water, improvement of nutrition and productivity of small ruminants (sheep and goats), and rehabilitation and management of rangelands. In the Central and West Asia and North Africa (CWANA) region, ICARDA is responsible for the improvement of durum and bread wheats, chickpea, pasture and forage legumes and farming systems; and for the protection and enhancement of the natural resource base of water, land, and biodiversity.

The Consultative Group on International Agricultural Research (CGIAR) (www.cgiar.org) is a strategic alliance of countries, international and regional organizations, and private foundations supporting15 international research centers that mobilizes cutting-edge science to promote sustainable development by reducing hunger and poverty, improving human nutrition and health, and protecting the environment.
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