Checking cassava plantations for signs of pests and diseases, near Khorat, eastern Thailand. Photo by: Neil Palmer / CIAT
Crop diseases can be devastating not only to farmers but also to the society as a whole.
Back in the mid-19th century, for instance, a massive famine swept across Ireland, killing around a million people. The most likely cause of this Great Famine, also known as the Irish Potato Famine, was Phytophthora infestans, a pathogen that attacks potato. At that time, about a third of the Irish population depended on this crop.
In addition, crop diseases just don’t stay within a country’s territory. Globalization is part of the reason, allowing for easier trading of agricultural products — some of which may carry pathogens — across borders.
In 2015, for example, plant protection scientists detected the cassava mosaic disease (CMD) in Cambodia’s Ratanakiri district. The virus that caused the disease was closely related to the species that devastated cassava fields in Sri Lanka and India, some 3,000 kilometers away. The disease actually originated in Africa, where CMD wipes out more than 40 percent of cassava production every year, as per some studies.
To prevent situations like these in the future, CIAT scientist Monica Carvajal has an idea: to develop a global crop disease surveillance system.
The idea came to her after she and some CIAT colleagues confirmed CMD’s presence in Cambodia in 2016, which at the time was limited to one district. She realized then that no matter how advanced the diagnostic tools used and no matter how quick experts would report a disease, those were not enough to prevent its spread.
The system, as envisioned by Carvajal, will go beyond using the smartest tools to detect pathogens, which refer to organisms that harm plants such as viruses, fungi, bacteria, and phytoplasma. It will also include recommendations on how to best communicate the presence of emerging diseases to authorities and prompt necessary actions to avert a massive outbreak.
Overall, the goal is to help build the capacity of countries in preventing, diagnosing, responding to, and recovering from crop diseases.
“CIAT, in addition to the breeding programs and conservation of crop diversity, has expertise in diagnostics, having developed tools for discovering, locating, and confirming pathogens. Still, crop diseases are happening, affecting societies and countries. So there’s more to this than early detection. The question is: What can we do to prevent an outbreak or, in the worst case scenario, to recover efficiently from one?”Monica Carvajal
The presence of a plant disease is a sensitive issue for some countries. Some governments hesitate to acknowledge that especially if their economies depend on the affected crops, fearing it would trigger investment pullout or hurt trade.
A lack of acknowledgment, however, could delay actions to control the spread of a crop disease. And before anyone knows it, a disease found in only one district a month ago has now spread to surrounding regions. In a few months, it could be in neighboring countries.
And that would actually be costly. Crop diseases, in general, lead to higher prices of farming inputs, reduced harvests, and overuse of pesticides, harming the environment and humans.
“As they say about health care: Prevention is better than cure; it’s definitely less traumatic,” Carvajal said. “The problem with prevention, however, is that the benefits are not tangible. Most will only realize them after an outbreak occurs.”
To start the ball rolling on developing this system, she is convening a gathering this month at the Rockefeller Foundation Bellagio Center in Lake Como, Italy. The center’s mission is to support “individuals and organizations who are working to improve the lives of poor or vulnerable people globally by convening prominent experts, influencers, and other key stakeholders to advance knowledge and form new partnerships, financial commitments, and initiatives.”
The Feb. 12-16 event will bring together a group of experts from around the world and from various fields — pathologists, economists, geneticists, geographers, statisticians and entomologists, among others — reflecting the multifaceted nature of plant protection.
Carvajal said she looks forward to learning from the experience of well-established organizations working on the issue such as the National Plant Diagnostic Network (NPDN) in the United States, the European and Mediterranean Plant Protection Organization (EPPO), and CABI.
“Developed countries have had success predicting and managing crop disease outbreaks; it would be an achievement to have the same system in less developed countries and promote food security around the world,” Carvajal added.
The event is expected to yield a plan on how to move forward with building the system with the support of international donor agencies. The road map will include its components, as well as its actors and their roles. It will also explore how big data can help in detecting and reporting plant pathogens.
One outcome could be a set of recommendations that can be modified depending on the crop and the context in each country. That might include breeding for disease resistance. In this case, gene banks, will play a key role. CIAT and its partners are now working on determining the genetic information of cassava’s crop wild relatives, partly to know which ones have resistance to certain diseases. It’s part of a broader effort to build a CIAT digital gene bank, which will catalog genetic traits of the more than 67,000 accessions or plant samples of beans, cassava, and tropical forages that the center has collected over several decades.
The conference on “Building resilience against crop diseases: A global surveillance system” is supported by the Rockefeller Foundation and will be held Feb. 12-16, 2018, at The Bellagio Center in Lake Como, Italy. Simone Staiger, Head of Knowledge Management and Learning at CIAT, is facilitating the meeting.
The following experts will join the event:
- Andy Nelson, Geographer/Remote Sensing Spatial Analysis, University of Twente, Netherlands
- Karen Garrett, Statistics/Pathologist, University of Florida, USA
- Kitty Cardwell, Entomology and Plant Pathologist/former National Director of NPDN, Oklahoma State University, USA
- Baldissera Giovani, Biochemistry and Molecular Biophysics, EPPO/Euphresco, France
- Diane Saunders, Pathologist/NGS Diagnostics, John Innes Centre, U.K.
- Monica Carvajal, Virologist/NGS Diagnostics, CIAT, Colombia
- Sophien Kamoun, Pathologist/Molecular Genetics, The Sainsbury Laboratory, U.K.
- James Legg, Entomologist/Epidemiologist, International Institute of Tropical Agriculture, Tanzania
- Joe Tohme, Agrobiodiversity Research Director, CIAT, Colombia
- Valérie Verdier, Pathologist/Genetics, Institut de recherche pour le développement, France
- Jerrod Lessel, Geospatial Analyst, Gro Intelligence, USA
- Richard Neher, Physics/Epidemiologist, University of Basel, Switzerland
- Philip Pardey, Economist/Policy, University of Minnesota, USA
- Roger Day, Coordinator, SPS, CABI, Kenya
- Jan Leach, Molecular Pathologist/Microbiome, Colorado State University, USA
- Angela Records, Research Advisor, U.S. Agency for International Development, USAID,
- Blake Bextine, Entomologist/Program Manager, Defense Advanced Research Projects Agency, USA
- Maria Lodovica Gullino, Pathologist, Torino University, Italy