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Diplomacy in Action

Emerging Plant Diseases in the Context of Ecosystem Services


Remarks
Office of the Science and Technology Adviser
Dr. Jean Ristaino
Washington, DC
April 23, 2013

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Lawrence Lin:  Good morning, everyone. Welcome to the Jefferson Science Lecture Series. My name is Lawrence Lin. I work for the Science and Technology Advisor to the Secretary, Dr. Bill Colglazier. He regrets not being able to be here today. We’re also missing the USAID Assistant Administrator, Paul Weisenfeld. He must be caught up in something, but if he arrives later, perhaps he can close out the lecture.

Just a few words about the Jefferson Science Fellows Program for those of you who are unfamiliar. It’s a program that brings senior faculty from universities here to the State Department to work for one year at State Department and USAID. It’s a public-private partnership. The State Department covers local living expenses and the universities cover salary and benefits, for which we are very grateful.

The program was started in 2004. We have 66 Jefferson Fellow alumni, 12 current Fellows, and 13 brand new Fellows coming in the fall. So it’s my pleasure today to introduce Dr. Jean Ristaino. She is a William Neal Reynolds Distinguished Professor of Plant Pathology at North Carolina State University. She is a Senior Science Advisor and Jefferson Fellow at USAID in the Bureau of Food Security in the Office of Agriculture, Research and Policy. She has a portfolio of issues over in her office which includes plant diseases, human and institutional capacity development in the Feed the Future countries, which is President Obama’s initiative.

Back at her lab, she studies population structure of the famed Irish Potato Famine pathogen, which is a global threat to food security. She’s pioneered plant pathogen forensics research and was the first to study the population genetics of historical epidemics. She also directs the Global Plant Health Program at N.C. State University and teaches Tropical Plant Pathology, and has done research in Central America, Brazil, and Asia. Please join me in welcome Jean Ristaino.

Jean Ristaino:  Thanks, Lawrence. I need to make a disclaimer before I begin that the views presented in my talk today are my own and do not represent those of the U.S. Government. The outline today of what I’ll discuss, first of all, I’m going to talk about ecosystem services and what they are, the impacts of population growth on ecosystems, then I’m going to move into plant diseases and how they impact food security and national security. I’ll give some historic and present-day examples and then I’ll discuss the armed-and-dangerous plant pathogens and how they affect staple food crops. And then what countermeasures can we use, can we scale up and deploy new technologies to manage these diseases, and can we manage the diseases in the context of ecosystem services.

The 2012 PCAST Report stated that the U.S. is the undisputed world leader in ag production, but we have many challenges that we face, including at the top of the list, managing pest pathogens in invasive plants, increasing water use efficiency, reducing the footprint of agriculture, growing food in a changing climate, managing the production of bioenergy, producing safe and nutritious food, and assisting with global food security in maintaining abundant yields. So plant pathogens are at the center of many challenging issues in food production, globally, and we need to be reducing environmental footprints of agriculture while maintaining yields.

Now, ecosystem services are the benefits that humans derive from ecosystems. If -- generally when we think about agriculture, we think about food production and increasing yields, when in fact the new alliance, the G8 initiatives, always talk about targeting higher yields for food production. Can we increase yields and manage plant diseases which significantly reduce yields, but also optimize these other supporting services, including nutrient cycling, soil formation, primary production, the regulating services, including climate regulation, disease regulation, water purification, and then cultural services?

This model, and don’t be taken aback too much by this, this is an ecological framework that was published by Cheatham et al, Karen Garrett was the senior author, and it discusses beyond yield, plant disease and ecosystem services. And you can see that plant disease pressure is at the center of the framework. Many methods that are used for managing plant diseases, such as tillage of soils, or new resistant varieties or application of pesticides, can have direct effects on many of the ecosystems services shown on the right. Application of pesticides can affect water regulation and water purification. Tillage can affect soil formation. Resistant varieties can affect primary production, because plant diseases reduce crop growth and affect primary production.

Then the policy area shown over here, the farm bill in the U.S., puts greater pressure on the abundance of few crop species. And payment for ecosystem services can definitely benefit biodiversity. Plant biodiversity in fact can also impact plant disease pressure, because when you don’t have monoculture and have diverse plant cropping systems, you have less plant disease pressure. So there’s a complex, interacting web of effects of plant disease on ecosystem services, and I’d kind of like to frame the whole presentation in that context.

Until the 1800s, the world population was less than a billion, and now it exceeds 7 billion and is increasing. Sixty percent of the people in the developing world have a lack of basic sanitation, one-third have no access to clean water, and a billion people are illiterate, including two-thirds of them who are women. Fifteen million babies are born to women between the ages of 15 and 19, so clearly human population growth and the need for food is having a huge impact on ecosystem services. The Millennium Ecosystem Assessment stated that over the past 50 years, we’ve changed our ecosystem more extensively than in any comparable period, and it’s mostly due to food, fresh water, timber, fiber, and fuel production, and it’s led to a loss in biodiversity on the Earth.

We have a moral imperative to improve global food security and to increase food production, but we need to do it in a holistic and systems approach. Plant diseases can have a huge impact on global food security and national food security. This is a famous painting by David McDonald showing a family in Ireland uncovering potatoes that had rotted from the potato famine. Late blight, the pathogen that caused the potato famine, occurred in 1843, and this epidemic in Ireland led to the death of more than 2 million people and immigration of another several million people. And I’m curious, how many people in the audience can claim some Irish descent in their lineage? So about half the people in the room, but actually 40 million people are of Irish descent. People, when they emigrated from Ireland, didn’t make it across very well and died of other human diseases -- typhoid, cholera. There’s a mass burial ground up in Canada, Grosse Isle, where 5,000 Irish immigrants are buried, and this is a statue in Harvard Square: “Never again should a people starve in a world of plenty.” But unfortunately that’s not the case, and in fact people are starving in a world of plenty in many places in the world.

Plant diseases and Phytophthora infestans, this study was done to describe a species in the 1840s, actually 30 years before Pasteur’s germ theory was documented, and it was M. J. Berkeley and Anton DeBary that described and named Phytophthora infestans. As I mentioned, plant pathogens are still causing famine. In the 1940s, in 1943, there was the Great Bengal Famine, where a brown spot of rice caused about 1.5 to 4 million to die of starvation. Some of the issues around this disease occurred during World War II, when political decisions were made to move food to feed soldiers rather than the small holder people in India, and this led to mass death and starvation, due to a plant pathogen.

In Uganda in the 1990s, cassava mosaic virus reduced the yield of cassava from 30,000 to 3,000 hectares, and led to starvation and migration of people. This is a map of the country showing how the disease expanded through Uganda, and in fact, girls were sold into slavery, sold off early into marriage in exchange for food, for cassava.

The coffee rust epidemics of 2013 have led to a state of emergency in Central American countries. I just returned from Guatemala this week where we had a summit to discuss how to handle this disease. 40,000 farm workers are losing their wages, and there’s going to be hunger in the region in the coming years since they are losing their ability to harvest and pick coffee in the region. They are estimating $500 million in disease losses this year, but the impact will be in the following two years because the impact of disease this year is going to affect yield next year.

Disease can also impact national security from not just an accidental introduction state, but from deliberate introductions. Back after 9/11, President George Bush stated that, “Disease has long been the deadliest enemy of mankind, and civilized nations need to reject biological weapons use.” Plant pathogens have been used as biological weapons in the past. The National Academy published a book called “Countering Agriculture Bioterrorism,” so not only accidental release and movement of pathogens, but deliberate release has been an issue.

So what are the most wanted plant pathogens, most wanted in terms of the armed and dangerous list? This was a publication that was done in Science in February 2012. It lists potato late blight at the top of the list, stem rust of wheat, black sigatoka of banana, rice blast and this cassava mosaic disease. Also, aflatoxins were not on the list, but they’re a serious threat to food security in many parts of Africa because of the toxic aflatoxins that are produced by Aspergillus flavus. It affects corn and peanuts.

So these are the armed and dangerous plant pathogens. They have significant impacts on ecosystem services. This is the black sigatoka pathogen Mycosphaerella fijiensis. It’s a major problem in Central America on bananas. I took these photos on a Dole plantation in Guapiles, Costa Rica. They have to spray 50 fungicide applications a season by aerial airplane to control sigatoka. This pathogen was introduced accidentally into Honduras in the United fruit plantations in the 1970s. It wasn’t present before. And now, due to the pathogen, there is expensive fungicide use and resistance to the fungicides that are sprayed.

So what are the characteristics of emerging plant diseases? They’re caused pathogens that have increased in incidence, geography or host range, they’ve changed in pathogenesis, or they’re newly evolved and they may have been discovered or newly recognized. Late blight is considered a reemerging plant disease, and it’s a constraint to food security because the disease has increased greatly from its first introductions into Ireland and the U.S., and is actually a global threat now to potato production all over the world. This is Honduran farmer whose field I was in a year ago. His field was completely wiped out by late blight because he didn’t have access to chemicals for control of the disease.

When the pathogen first entered the U.S. in the 1840s, it entered around the Port of New York and Philadelphia, but it quickly expanded its range. And in Ireland two years later, first entered in Belgium, expanded both directions into Europe and completely caused devastation on the food crop in Ireland. At that point in time, potatoes were the main food crop of the peasant farmers, and they had no other food source, and that’s why they succumbed to the disease. Similarly today, in Africa, where cassava is a main food source, when the crop is diseased it significantly impacts food security.

Another pathogen that has changed in pathogenesis is the new virulent race of Puccinia graminis. A strain called UG-99 was first discovered in Uganda in 1999, and it’s quickly spread over the years into Kenya, Ethiopia, into Yemen, Syria, and is moving into Pakistan and India. And USAID, through funding to ARS scientists, are working to plant resistant varieties in Pakistan and India so that the crops there are not affected by this virulent strain. Norman Borlaug, before his death, had a call to action and suggested that all the advancements from the Green Revolution would be for nothing if we didn’t eliminate this strain and breed resistant varieties because the varieties that were bred during the Green Revolution are susceptible to UG-99.

So plant pathogens change in aggressiveness. This is the stem rust pathogen. Those spores are aerially dispersed a long distance across large areas through aerial dispersal, and some people relate the plant diseases to the Red Queen from “Alice in Wonderland.” The plants really need to keep running just to stay in place in terms of evolving resistance to the pathogens that are continuously evolving. So crop species are in an arms race with pathogens, and we continually need to fund research to find more stable and durable resistance to these diseases.

Another important disease that was newly recognized was not even known in the U.S. until about eight or nine years ago is Phytophthora ramorum. This is an aerial shot of trees in the Marin County area of California, dying from Phytophthora ramorum. The pathogen was described on nursery crops in Europe and it’s not clear how it was introduced onto the West Coast, but it’s completely changed the biodiversity of the crop species there. Its killing major forest species such as bay laurel and Oregon Myrtle, and rhododendron is very susceptible.

So other newly evolved strains that are emerging in Africa include this cassava mosaic virus. You have cassava mosaic and brown streak. It’s a virus that infects the foliage of the cassava plant, and then also affects the tubers. This is a healthy root system and they are cassava mosaic- and brown streak-infected cassava roots. This pathogen is interesting. Cassava is from South America, however, the pathogen may have actually jumped hosts from some indigenous plant species in Africa into cassava when it was introduced into Africa from South America, because these viruses aren’t known in South America. So there was a host or a reservoir host somewhere in Africa, and it’s not clear what that was, but these viruses moved into the crop after the crop was introduced. And as I mentioned, there have been millions of dollars worth of losses.

So many plant pathogens -- actually, one of the characteristics of pathogens and drivers of emerging plant diseases, the viruses are a large percentage of -- if you look at this pie chart—a large percentage of introductions are due to viruses because they’re not easily detected in the plant material. Fungi and bacteria are more easily visible. And the largest way that pathogens move in plant material is through the introduction of plant species that are infected with the pathogen. If we look at bacteria, fungi, and viruses, plant introductions are a major way in which bacteria and viruses are introduced, and fungi, but weather has a larger impact on the fungal and the bacterial plant pathogens.

So pathogens move in trade and they move in infected plant material, and globalized trade has been a major driver for the increased frequency of plant pathogen introductions. And as this headline in USA Today indicates, “The 2012 Deadline to Scan all Port Cargo Won’t be Met,” it’s basically impossible to scan cargo and plant material completely to rule out the movement of pathogens. Only some subset of plants are actually screened by APHIS in the U.S., or elsewhere globally. So plant pathogens move around in plant material.

Other drivers of emerging plant diseases include climate change, as I mentioned. You can have a distribution of change in pathogens, or a distribution of vectors. Increased frequencies of weather events can cause diseases to emerge. Drought stress predisposes corn and peanut to aflatoxins. And then milder winters are allowing pathogens to survive at -- for longer and in different areas where they wouldn’t normally survive.

In developing countries, the increasing intensity of nontraditional crops that are actually being planted has also led to increases in introduction of pathogens in fruits and flowers and vegetables. And then the fact that 40 percent of the world’s food crops include four staples, and monoculture of these crops is indicative of the loss of genetic diversity that’s a major issue when pathogens emerge. Host-parasite evolution is occurring. I mentioned the host jumped from wild species into cassava, but there’s other viruses that have moved into bean crops from other hosts, and just interspecific hybridization of pathogens.

I just returned from a coffee rust summit in Central America, and I think coffee rust is going to be the poster child for climate change impact on a major export crop. The disease that causes coffee rust is caused by a fungus: Hemilia vastatrix. These spores are windblown. It was first introduced into Brazil in the 1970s and then moved into Central America shortly after that time. Most of the coffee varieties grown in Central America lack resistance to the disease, and they found more disease at the high-altitude, shade-grown coffee plantations. And these plantations generally did not have coffee rust in the past, so the coffee growers don’t use fungicides, and the lack of fungicide use in the shade-grown coffee areas by the small holders has led to a widespread epidemic. Many of the plantations are 40-years-old. They’re perennial crops. This is a plantation that I visited just last week. They’re completely defoliated and coffee yields will be reduced significantly due to this disease. And I think climate change is a major driver in the significance and emergence of the pathogen.

This is just a diagrammatic showing weather events just before and during the harvest periods can increase temperatures, shorten the latent period and high-altitude stands then behave as if they are low-altitude coffee. And low rainfall, but rainfall enough for germination of the spores on the leaves increases dispersal, and then due to the low price of coffee and dive in coffee prices, growers don’t spend the money for fungicides or fertilizers, and this impacts disease as well, so no preventative controls have been used.

These are just some plantations growers are now going through, and they call it stumping where they cut back the plantation completely. Within two years, they’ll have regrowth and they can harvest coffee beans again so they’re out of production. And the other big impact, climate change is impacting the disease, but the disease is impacting climate because a large area of Central America has dead coffee plants right now, so that carbon sequestration that the plants would have sequestered is no longer happening over large areas of Central America due to this plant disease.

Potato late blight is a reemerging pathogen. As I mentioned, it’s the pathogen system I’ve worked on for many years. The pathogen infects tomato and potato, and also the tubers and the fruit, and this pathogen has re-emerged because it has a very dispersal mechanism, it can move in crop material, has a polycyclic nature -- meaning repeated spore production over the season -- there are fungicide-resistant strains, the pathogen can move into wild hosts, and the genome of the pathogen is very plastic and it’s able to overcome host resistance genes.

And then all the potato production in the U.S. is in susceptible varieties, and growers have to spray fungicides. In fact potatoes are sprayed more than any other food crop because of potato late blight. And we found fungicide resistance. This is a field in western North Carolina. Ten to twelve sprays a season just to control the disease on tomato. We have resistant strains developing to one of the common fungicides, metalaxyl.

In 2009, we had an outbreak of late blight in the U.S. that made it on the front page of the New York Times. This pathogen -- a strain that we identified in our lab, Us22 -- was actually moved in tomato transplants. The Bonnie Plant transplants that you can buy at Home Depot or Wal-Mart were infected with late blight. They went into peoples’ backyard gardens and then from there moved into the field crops, tomatoes and potatoes, in the Northeast. The potato growers sprayed, but organic tomato growers were wiped out by late blight. If we were only eating potatoes and tomatoes at that time, we would have had a food emergency in the Northeast, but in the U.S. we have a diversity of foods so it was an epidemic that was serious for organic tomato growers, but otherwise we were able to handle the epidemic and identify the strain. But what’s interesting is that it was just a single source, a single growing location in Alabama, where this pathogen originated, and then it was sent to stores throughout the Northeast, and then from there spread all over the Eastern part of the U.S. So this just shows you a means by which a pathogen can spread rapidly. This was over a period of a month and a half. It went from one location to backyards in every area in the Northeast.

So what are the countermeasures we need and what technologies do we need to manage these emerging plant diseases? Well, for late blight we’ve been working on a global surveillance and reporting system using Google mapping, but in many countries there’s a lack of reporting because of exports. People want to be able to export their crops, and if the diseases are known and reported they have issues exporting. But I think we have technologies now, satellite imagery, and other methods to detect pathogens so that we can prevent some of the spread.

And many of the epidemiological aspects of biosecurity initiatives, including monitoring, sampling, methodology, risk assessment, these all need to be done for some of these major pathogen species. We can use information and communication technologies and web-based disease forecasting to monitor spread, and then use decision support systems to forecast when fungicides need to be sprayed, and disease alerts can be sent on smartphones. So this use of information technology can be used to monitor spread and prevent the spread of pathogens. We developed a system in conjunction with collaborators called USA Blight. This is late blight on potato, and we have a series of collaborators throughout the U.S., growers and extension faculty, that report the disease.

This is just a series of maps I want to show you. The pathogen over winters in Florida on tomatoes, that’s where the winter tomatoes are grown in the U.S., and then we’ve mapped out the occurrence, you see, of spot coming up in North Carolina and up on Long Island and New York. Some of this is due to tomato movement, some is windblown spores. And you see over time we’ve been able to map out occurrences of the disease. At the same time, we’re actually mapping the genotypes of the pathogen. We’re testing fungicide sensitivity and we’re using microsatellite analysis to tell what strains are where.

These types of mapping systems could be used for coffee rust, it could be used for other crop pathogens in the developing world, because you can archive the maps, you can look at interventions that might reduce disease over time and see how that’s impacted by going back to the archival maps. We’re using microsatellites to genotype major lineages, and my laboratory has also done some forensic work with Phytophthora infestans. We’ve recently sequenced the genomes from samples from the Irish potato famine from the 1840s, and we’ve found that there are two distinct lineages that were introduced between the 1840s and the 1870s into Europe, and these are more modern lineages. This is based on 4-5-4 sequencing of entire genomes, so genome-sequencing technology’s allowing us to track migrations and to look at genetic relatedness of strains.

So I think that next-generation pathogen genome-sequencing could be a countermeasure to track sources of an inoculum of pathogens. We know with phytophthora infestans, we had a team of about 25 faculty that worked on this genome sequence. We published it and there was a picture on the cover of “Nature” a few years ago, but we found that the genome is highly expanded and that there are effector proteins in the pathogen genome that mutate in response to host-resistant genes. So in fact what may be driving this genome expansion is the crop breeding that breeders are using to manage the disease in the first place. So being aware of how genome pathogens evolve in response to host genomes is important so we can stop that evolution or slow the evolution of diverse strains.

Another countermeasure is improved diagnostic capabilities. We are funded through the Horticulture CRSP project to do training. We’ve trained students in Central America to do disease diagnosis and we have a second workshop planned for October at the Pan-American University in Zamorano. Many of the developing countries in Africa and in Central America do not have diagnostic capabilities, and they do not always use molecular diagnostics to clearly identify different strains of pathogens, and so we’re trying to improve the infrastructure for disease diagnosis through these training workshops. And I hope to run a workshop in Africa and in Asia in future years.

Plant breeding is an important mechanism for controlling diseases, and with late blight, transgenic potatoes have been developed that have this RB gene. And there’s been policy issues in terms of deployment of this, but these transgenic potatoes are now being tested in Africa and were tested in a set of wide experiments over Bangladesh, and what’s very impressive about this transgenic potato is that generally you have to spray potatoes ten to fifteen times. The RB potato? With one spray you can reduce disease. It’s not completely immune, but it’s highly resistant, and transgenic potatoes can significantly reduce pesticide use and that’s a good thing and the policy teams at AID are trying to improve the policy structure in several countries so these potatoes can be adopted and planted in large areas in the field.

So sustainable intensification is what we need in terms of crop production, investment in and diffusion of agriculture science and technology that can sustain food increases without harmful tradeoffs from excessive pesticide use or water nutrient runoff. In the “FAO 2012 State of Food and Agriculture,” This document recommends investing in public goods yields high returns in ag and growth in poverty reduction, and there’s evidence from many countries that over five decades have shown that public investment in R&D is important. Also an education in rural infrastructure yields much higher returns than other expenditures such as input subsidies.

So R&D, research and development, and deploying technologies that can manage diseases in the developing world are important. Governments must also invest in building institutional and capacity necessary to support an enabling environment. And this enabling environment also includes policies for deployment of transgenic technologies that can significantly reduce disease when growers don’t have access to fungicides. So there are promising and effective responses to reduce degradation of ecosystems due to agriculture, removal of production subsidies that have adverse economic, social, and environmental effects, improving policies that promote the safe use of transgenic crops, application of a mix of regulatory and incentive and market based mechanisms to reduce overuse of chemicals and fertilizers, and use of response policies that recognize the role of women in production and use of food that are designed to empower women, ensure access to, and control of, resources necessary for food security.

In Africa women are central to the feeding of people. They are the smallholder farmers -- a large percentage of the farmers are women and many of them don’t have access to resources. So AID is busy working on gender issues to promote education and training of women in agriculture. I just recently received a grant from the Keck Futures Initiative to coordinate and fund a network of U.S. scientists and pathologists that will train PhD-level promising women in agriculture research. And the idea is to train a nucleus of women that would be experts on these major emerging pathogens like cassava, light blight, the rust pathogen, rice diseases -- all of the main armed and dangerous plant pathogens. And with that I will take any questions.

And if you have a question, can you go to the microphone because they’re recording this and they want to capture your question.

QUESTION:  Thank you for the presentation, Jean. Great presentation. A question for the -- for example the blight resistant potatoes. When you are testing them in your lab or in the test facility, do you expose them to the same stress condition that they could face, for example, when you send them to Africa or to Latin America, in terms of the climate change and the high temperatures, low rainfall or flood, that could tell you if those will withstand the conditions where you are intending to send them?

JEAN RISTAINO: The RB potatoes were developed through research collaborations. My lab didn’t develop the potatoes, but they were developed through research collaborators at ARS and Cornell University, and there are trials underway now in Bangladesh, all over the country, and also recently approval has been given to test them in Uganda. So they are going to be tested in different environments. They’re resistant to late blight. Now I don’t know that they are more water-use efficient or they’re drought tolerant. Those kinds of genes haven’t been pyramided into these potatoes. They are specific for late blight resistance. But just getting the trials out in the field has been a major effort that John McMurdy in our group has been working on. Yes?

QUESTION:  You mentioned the deliberate release of pathogens as an issue. Are there governments or evil non-state actors out there trying to destroy the world’s food supply and wouldn’t this be considered bio-warfare or bioterrorism?

JEAN RISTAINO:  Are there evil actors out there trying to destroy the world food supply. In the past bio -- crop-bio terrorism has been used. There are documented, unclassified reports. During World War II the Japanese spread late blight into China. We’ve actually genotyped strains in China, and you can find the original strain that was introduced there. Also during World War II the Germans dropped Colorado potato beetle on the U.K. to kill off the potato crop. Saddam Hussein had stem rust facilities under his regime. So evil actors have weaponized plant pathogens. You know, are they going to be used in the future? Hopefully not, but they have been in the past, and that’s one reason why we need to be aware of what’s coming in at our borders and be able to quickly genotype using molecular diagnostics and identify where pathogens are introduced. The most commonly -- they’re introduced accidentally through trade. You know, I mentioned the black sigatoka example in Honduras? United Fruit was trying to breed resistant bananas and they introduced the pathogen in Honduras in 1973, and it spread all over Central America. So it was an accidental introduction. And generally that’s how things occur. And, you know, training diagnosticians, building up plant disease clinics to be able to detect pathogens is very important. In the U.S. we have a National Plant Diagnostic Network and after 9/11 they were energized and deployed to be testing, and monitoring, and reporting pathogens so that we can be aware of things coming into the U.S.

QUESTION:  So would you say protection from accidents and transmission innocently through commerce is the same -- those measures would be the same measures that would protect us from deliberate transmission?

JEAN RISTAINO:  I would say yes, it would help.

QUESTION:  Could you expand a little bit on the coffee rust with the summit that you recently had in Guatemala? Had there been any coffee varieties that had been identified at this point that have any -- shown any resistance to this disease at this point?

JEAN RISTAINO:  The three most common coffee varieties that are grown in South America - caturra, catuai, and bourbon - are all susceptible to coffee rust, and most of the acreage in Central America is planted to susceptible varieties. Although there are resistant varieties that have been developed and they’re out there in small areas -- Costa Rica probably has more resistant varieties planted. And actually, an outcome of the Coffee Rust Summit, the World Coffee Research Institute wants to do a big variety trail screening 30 varieties at about 10 different locations globally. Most of the resistant varieties are not actually planted. The Columbians had a variety that was resistant but the quality -- the cupping quality was bad so the industry didn’t adapt -- you know, uptake that variety and plant it in the field. So that’s a big issue with coffee. You have to have -- maintain the flavor and the cupping quality, and also the disease resistance.

QUESTION:  So do you it then -- the disease making its way further south then towards, you know, eventually reaching towards Costa Rica?

JEAN RISTAINO:  The disease is in Costa Rica. It was reported in Brazil in the 1970’s and moved up into Columbia. It’s throughout every Central American country right now. Costa Rica’s been hit -- the large growers in Costa Rica have been hit less than the smallholders because they use fungicides. They have the money in these larger plantations to control the disease with fungicides. It’s the smallholder farmers that have not had access to fungicides, can’t afford it, or have never seen the disease at higher altitudes and haven’t bothered to use a fungicide. That’s why there are problems. As far as I know there’s no resistance, fungicide resistance to these chemicals, but you know that’s because they haven’t been sprayed that much but, you know, that could be a possibility in the future. But resistant varieties -- you have to weigh out resistance versus the quality. And even if they replanted many of the plantations with susceptible varieties, but sprayed them with fungicides, they’d be fine. You know, they would be better in a couple of years. They can take alternate rows out and plant with the susceptible variety but just spray them. So there’s all sorts of options. But money is an issue right now for these growers. With the coffee prices low, like $1.80 a pound -- Starbucks sells their coffee for $14 a pound in the U.S. They’re paying $1.80 a pound to the growers. That’s a problem for these smallholders, you know, they can’t afford the inputs.

QUESTION:  Hi. Thanks so much for your talk. You answered part of my question but I was wondering -- you mentioned fungicidal -- use of fungicides and also stumping, and I was wondering what was most commonly used, or what other strategies are used by people once you’ve identified what you’re dealing with?

JEAN RISTAINO:  In coffee, pruning back and fully stumping the plantations is used most widely right now because it’s just manual labor to get in and stump them. Fungicides in the large plantations are used routinely to manage this disease, and those are pretty much the two options right now other than planting resistant varieties. The Columbians developed this resistant variety but the folks in Central America have their small -- whole areas where they have higher quality susceptible varieties that they market and so they want to -- there’s going to be some reluctance to accept some of the new varieties because of the cupping quality. And plus, there’s this allegiance to these plants that have been on their plantation for 40 years. They’re almost like wine grape growers. They don’t want to turn over the plantations very frequently. Some growers have -- their fathers or grandfathers have planted some of the coffee and they don’t want to replant. So pruning back a coffee plant within two years, it will regrow and then spraying fungicides is probably the best option. John?

QUESTION:  John Bowman with USAID. Just wondering if you could talk a little bit about the -- kind of the hot potato, the transgenic application -- the solution and, as a food security solution, you know. Under Feed the Future we’re having to -- we have these huge increases in population and the good agricultural land is decreasing and we have to hit these, like 70 percent yield increase targets from 2010 more or less to 2050. So how can you do -- you know, how can you -- just some commentary on how we might be able to do this without transgenic biotechnology, and why does the -- you know, the certain governments and NGO groups, you know, what don’t they like about these huge decreases in pesticidal sprays that you can get? I just -- as an academic -- and I was just wondering if you could give -- talk about some of the flavor of the controversy and how can we possibly hit those targets without, you know, transgenic biotechnology. Do we have a chance, do you think, without it?

JEAN RISTAINO:  Well, with rice and wheat there are varieties that are non-transgenic but conventionally bred varieties that are higher yielding or drought tolerant. They’re using nutrients more efficiently. And some of those targets can be met with conventional technologies. With potatoes, most of the resistant varieties that are conventionally bred are not totally resistant. They still have to be sprayed. And, as I mentioned, Phytophthora infestans can overcome these R genes in the host. So, what the breeders are doing now with potatoes is pyramiding these R genes, trying making more durable resistance -- and they’re pyramiding them using transgenic technologies, putting two and three genes in the potatoes. And I think potatoes are a good example, where you spray 15 times versus with the transgenic you spray once, and it’s a really good poster child for beneficial use of transgenics. Just like with BT corn you can spray less frequently and have resistance to insects. Unfortunately, a lot of the transgenics that were first developed were herbicide-resistant varieties, and growers in the U.S. use more herbicides in response to those varieties being planted and I think that some of the negative press occurred because of the type of transgenics that were deployed originally. But I think there are applications of transgenics -- especially for smallholder farmers who can’t afford fungicides, they just have the right seed. And they’re planted -- as far as I know there have not been any negative environmental impacts from transgenic crop plants for food production. You know, the papaya virus resistance in Hawaii is a great example too, where the whole industry was saved because of those transgenic papayas. You know, and there’s probably going to be new technology in the next few years that are developed where -- they call it sysgenics where you can actually -- they’re not actually transgenic crop plants. They’re using the same host genes in the plant and they maybe get through the regulatory hurdles quicker. So -- but it’s definitely controversial and not always based on the science that’s out there.

QUESTION:  Hi. Hello, my name is Pace Lubinsky. I’m at USDA. Thank you very much for your talk. I had a couple of questions and a comment. One, we’ve heard a lot about -- in developing country contexts -- about the food waste and loss issue, and we further figure 30-40 percent, and I was wondering if you could talk a little bit about how much of that is due to plant disease, post-harvest loss.

The second question is -- back to this issue of the potato and the whole politics and controversy about biotechnology. And I was wondering if there is an effort at USAID, or otherwise maybe here at State Department, to try to engage some of the NGOs and some of the groups that I think -- you know, it’s a very small number of groups, is my impression, and very predictable the opposition, so I was wondering -- and I think even the motivation about why there is opposition to some of these crops that aren’t, you know, big commodity crops developed by trans-nationals -- I think we do understand some of that motivation. So I was wondering if there was an effort to actually engage some of these select groups to try to bring them to the table and identify a common ground, on a way forward.

And then the third thing I wanted to say is just to comment on the coffee and the rust. And I think it’s an interesting example of where the technology and innovation is there, again biotechnology not being a magic bullet. That there being other ways to manage the rust but that I think in terms of there being a lack of application of the new varieties, that I think it’s a good example of where the lack of enabling policy environments and regulatory clarity is a disincentive for public-private partnerships. Because I think public research -- it’s an example of where public researchers have developed the crop and may not have all the agronomic characteristics to really be commercialized, but there’s really not a -- it’s kind of a catch 22 because there’s not really an incentive for the private sector to be involved because at the end of the day there’s not the enabling regulatory environment to get that crop to market. So that’s more of a comment but it would be great to hear your thoughts on that. Thank you.

JEAN RISTAINO:  Okay. The first question was about post-harvest losses. 30-40 percent of the crop -- of many crops -- is reporting post-harvest losses. And I don’t know that I can quote an exact percentage -- of what percentage of those are due to plant diseases, but some of them are. On sweet potatoes there are these fungi that infect sweet potatoes in storage. In corn you have Aspergilis flavus that infects, causes afolatoxin, problems in the crop and its loss. So for many of the major food crops that are in Africa, some of the losses are due to plant diseases, some of them are improper storage due to not having temperature, environmental control. So I don’t know that I can quote an exact percentage but 30-40 percent of post-harvest losses. I’d say maybe half. John might be able to comment better because he just did a talk on post-harvest losses and diseases, but the percentage is there. I’m not sure.

The second question. When you talk about the deployment of transgenics and engaging the NGOs, the Greenpeace -- I think some of that is happening and has had been occurring in the past. There a scientist at IFPRI that’s been working with some of the NGOs, and John McMurdy in our group has been working with the policy group, to try and understand what the opposition issues are. And many times the regulatory hurdles are in the ministries of agriculture. And not necessarily opposition from Greenpeace, but just these regulatory hurdles that you have to go through each ministry of agriculture, in each country to get the approval. And so some of it is just bureaucracy hurdles. And I know they are working very hard on both of those -- end of things. And, you know, I think some of the success stories and examples where you can have reduced environmental impacts by using transgenics and less expense for growers, and the big multi-nationals aren’t involved, like the potato project, you know, came out of a university. So it’s not like the big multinationals are out to make money off of the poor smallholders in that example. So those are, I think, that work is going on, engaging the community. But from what I understand, it’s sometimes the bureaucracies and the ministries of agriculture, and the countries that are just holding things back. And the State Department can help with that, definitely through negotiations. And then the coffee rust, you talked about several things dealing with coffee rust, resistant varieties, and -- I kind of forgot what your question was.

QUESTION:  It was more of a comment, but just any thoughts you have on enabling environments and lack thereof in public-private partnerships.

JEAN RISTAINO:  Well, at the meeting I was at this summit in Guatemala this week, all of the major companies were there: Starbucks, the Specialty Coffee Association, Folgers, and the International Coffee Organization. And they are interested in bringing funding to the table to look at long-term and short-term solutions, and kind of integrated approaches. It can’t all just be resistant varieties because many of the growers want to keep the susceptible varieties but they just want input on managing these diseases, and access to the chemicals to use to control diseases. So, Syngenta Chemical Company is giving growers an option where they can pay for fungicides with coffee. Two bags of coffee per hectare and they can have access to the fungicides. They’re doing that in Brazil. It works when you have some coffee to pay with but in an area when you have a widespread epidemic, it’s going to have to be paid in future coffee. It’s kind of a little odd, you know, the chemical companies actually buying and selling coffee then, but it’s one way to get the compounds out to the growers that need them. And then, you know, there’s financing going on. The International Finance Corporation wants to back rehabilitation of the plantations. So there are many options. But the roasting community is very engaged because without the coffee growers they don’t have the crops to import, and a lot of the U.S. small roasters import from Central America and they -- Fair Trade Coffee was at this meeting and the Fair Trade Organization is working with the individual growers, so they’re putting up money and they’re interested in solving the problem. It kind of hit them by surprise, especially the high altitude growers, because the disease was never there before and it’s now at higher elevations. So that’s why I say that coffee rust may be a poster child for climate change because its showing the geographical expansion of a pathogen into an area where it’s never been before, due to these El Nino events and, you know, weather. So --

Any other questions? If not? Thank you very much.



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