Month April 2014

Meet the Experts: Fighting Plant Disease with Science and Technology

Meet the Experts: Fighting Plant Disease with Science and Technology


Meet Jean Ristaino, a 2012 Jefferson Science Fellow with USAID and William Neal Reynolds Distinguished Professor of Plant Pathology at North Carolina State University in Raleigh.

Last year at USAID, Ristaino supported the Feed the Future initiative through her work on plant diseases and human and institutional capacity building. We talked with her to learn more about her passion for food security and how science can help us end poverty and hunger.

Tell us a little about your research and academic interests.

I work on one of the most notorious plant diseases known to mankind: late blight of potato, caused byPhytophthora infestans, which was the culprit for the Irish famine more than 160 years ago. The wordPhytophthora literally means “plant destroyer” and it does just that: The disease can kill a potato field in a matter of days if left untreated.

Late blight is still a threat to food security in many areas of the developing world where smallholder farmers have limited incomes and lack access to fungicides to treat plant diseases.

More generally, I study plant disease epidemics, track disease outbreaks using geospatial surveillance systems, and monitor pathogens using genetic tools.

Plants and pathogens are in an “arms race.” We often use a concept from the Red Queen in Lewis Carroll’s Through the Looking-Glass to explain this concept: That one has to keep running to stay in the same place. Plants have to constantly evolve resistance to ever-changing plant pathogens if they are to survive.

What motivated you to work on these issues?

I lead the Global Plant Health Internship Program, funded by the National Science Foundation, at North Carolina State University and have been teaching tropical plant pathology for many years in Central America. My late blight research has also taken me to Asia, Central and South America, and Africa.

I’ve seen how plant diseases limit yields for smallholder farmers. Plant diseases have been reported to cause up to 40 percent of postharvest loss of staple food crops, and they can lead to food insecurity in regions where outbreaks occur, impacting national security.

I’m writing this blog from Honduras, where I recently taught a workshop on plant disease diagnostics for Phytophthora diseases, as part of the Feed the Future Horticulture Innovation Lab. My goal is to empower plant diagnosticians by giving them the tools they need to monitor plant pathogens that move aerially, in seed, or in propagation materials before disease occurs. What we want to do is prevent outbreaks instead of working in crisis mode to mitigate impacts once an outbreak occurs.

I’m also motivated to help train the next generation women agricultural scientists in Africa, who will help deploy the technologies needed to manage plant diseases and improve food security in the region. Women are the primary smallholder farmers in Africa and we need more trained African women scientists to work with them.

Your work on a strategy for coffee rust research while at USAID is particularly timely. How can science and technology help address this issue, particularly in Central America?

I’ve seen coffee rust in the past, but it only minimally impacted coffee plantations because growers have usually managed the disease with a few appropriately-timed fungicide sprays.

But in the past year, outbreaks of coffee rust disease, or “La Roya,” caused by the rust pathogenHemileia vastatrix, have made coffee plants lose all their leaves at many plantations over wide areas of Central America.

The disease is occurring at higher elevations on plantations that in the past had never experienced coffee rust. Climate change is expanding the geographic range of the pathogen and the pathogens themselves may also be changing. We need to genetically monitor the rust pathogen, identify races, and determine if new genotypes are present in the region so breeding can be effective long-term.

Central America needs to immediately deploy a coffee rust geospatial biosurveillance system to monitor both disease incidence and pathogen genotypes. This could be modeled after systems we already have in place in the United States for late blight and several other plant diseases. Efforts are underway to begin monitoring outbreaks.

In the short term, replanting plantations with tolerant varieties and providing access to timely fungicides before the rainy season will reduce disease.

To prevent further devastating outbreaks, we need coffee breeding programs that not only include variety trials conducted in various locations, but that also train students who will become future coffee breeders and plant pathologists.

What’s one thing you wish more people knew or understood about global food security and nutrition?

Plant diseases can impact food security. And food security is tightly linked to national security in many areas of the developing world. The correlation between food shortages and political instability is striking. Investment in agriculture research for development is strategically important to our nation’s security as well as the world’s.

Research to mitigate plant and animal diseases and make crops more resilient to climate change is a wise strategic investment. We have a moral obligation not only to help reduce hunger, but also to build the infrastructure in human and institutional capacity that countries need to sustainably produce nutritious food. 

How has the fellowship impacted you personally and professionally?

My year in Washington was incredibly rewarding. I have a better understanding of how diplomacy and development work, how politics influence science and development, and how USAID and its missions work. I experienced firsthand how passionate people at USAID are about feeding a hungry world.

I participated in many briefings on a variety of subjects related to food security at nongovernmental organizations, other government agencies, science think tanks, and local universities. I was able to hear speeches by the USAID Administrator, the Secretary of Agriculture, and the Secretary of State at a variety of venues. The networking was amazing.

I enjoyed the camaraderie of our cohort of Jefferson Science Fellows and we plan to stay engaged both at USAID and the State Department. I’m working on ways to improve communication among the past fellows using social media and networking tools.

Professionally, I’m increasingly being called on to consult on various international projects and am being recruited for director positions in international programs at international centers and universities. I enjoy mentoring young scientists from developing countries and I plan to continue to conduct research and affect policies that improve food security.

Stay tuned to the Feed the Future blog for future installments in our “Meet the Experts” series. 



Blog reposted with permission from USAID. To view the original post please visit: