Seeds of a Perfect Storm: Genetically Modified Crops and the Global Food Security CrisisNina Fedoroff, Science and Technology Adviser to the Secretary of State and to the Administrator of USAIDInaugural Lecture in the Jefferson Fellows Distinguished Lecture Series Washington, DC October 17, 2008 I welcome all of you to the first in what will be a regular series of monthly lectures by the State Department’s Jefferson Fellows. Before I get to the substance of my talk, I’d like to tell you a bit about the Jefferson Fellows. The Jefferson fellows are well-established academic scientists who come to the State Department for a year, bringing their scientific expertise to bear on our formal interactions with other countries. They find homes throughout the State Department and USAID – and they offer assistance and advice in their areas of expertise. Since we have them as captives for a year, we decided that it would be good to ask them to share their knowledge even more widely through lectures to the entire community on scientific topics of interest in our foreign relations. The next few lectures in this series are going to be given by alumni of the program. What you need to know is that the Jefferson fellows agree to be consultants for the State Department for 5 years after they’ve served their year here. This means that they can be called on to participate in any activity in which their expertise is needed – and many of them are willing to travel to other countries as speakers and as participants in international activities of interest to the State Department. You need only contact my office to obtain information on the areas of expertise represented among those in the current class of fellows as well as past fellows. We are currently arranging a reception to introduce the current class to all of you – please come and get to know them. They are a wonderful resource for the whole department. Well, I can’t miss the chance to address that oversight. I’ll start by telling you how we got here, how we planted the seeds of the stormy food security crisis of 2008. Then I’ll tell you how we’ve learned to improve food crops over the eons, then over the past century. And I will tell you how many countries have gotten themselves into the paradoxical position of rejecting the most promising and environmentally conservative means of ensuring global food security ever to have been developed. Since the introduction of science into agriculture in the late 18th century when Joseph Priestley showed that plants evolve oxygen by using a plant to keep a mouse alive, science and engineering have powered enormous gains in agricultural productivity through fertilizer production, plant breeding, and mechanization. In some parts of the world, not one person in a hundred is growing plants or raising animals for food. Science- and technology-based farming have freed us be scientists and politicians, artists, teachers, doctors, newspaper reporters – and diplomats. We buy what we eat in grocery stores, or restaurants, or fast food joints. . And yet, in many countries, particularly in Africa, the task of growing food is still done by such manual labor and by each family. Thomas Malthus published his famous Essay on Population in 1798 predicting that humanity was doomed to poverty and famine because the human population was growing exponentially, while mankind’s ability to produce food could only increase at a linear rate. He wrote at a time when the famous curve of human population growth was way down here (arrow). The ensuing science-based increases in agricultural productivity supported a tripling of the human population. Particularly important were the inventions of these two gentlemen, Haber and Bosch, who figured out how to convert atmospheric nitrogen to forms that plants can use – we call it fertilizer. This is now done in huge plants around the world. But around the middle of the 20th century, there was a resurgence of Malthusian predictions of mass famines in the populous countries of Asia whose agriculture had not yet benefitted from science. Perhaps the most famous catastrophist of this era was Paul Ehrlich, author of The Population Bomb. Remarkably, it took just a handful of scientists – principally plant breeder Norman Borlaug – to avert the predicted famines. He and others identified dwarfing mutations in wheat and rice that grew prolifically with fertilization without falling over. And they tirelessly promoted their rapid adoption, along with improved agricultural practices and increased fertilizer use. The resulting increases in food production underlie the rapid economic development that we are now witnessing in India, China and other parts of Asia and which are a driving factor of the current food crisis. The population has more than doubled again since the middle of the 20th century and the population experts are expecting another roughly 3 billion people to be added to the planet’s population by midcentury. That’s somewhere in the neighborhood of 9 billion people. Here’s a sobering factoid: the amount of arable land has not changed for more than half a century. And it isn’t likely to increase much in the future because we’re losing it to urbanization, salinization, and desertification as fast as we’re adding it. But somewhere between the first Green Revolution and the biotechnology revolution I’ll tell you about in a moment, the developed world seems to have declared the battle for food security won and moved on to other concerns. Investment in agricultural research has steadily declined over the past three decades, even as the human population has continued to grow. The successes of the first Green Revolution have supported rapid economic development in many countries. These advances out of poverty have stimulated demand for more meat, expanding the acreage used to grow animal feed. Oil is getting expensive, driving up the cost of fertilizer: it takes energy to crack apart the nitrogen molecules in the air and convert them to the forms that plants can use. And now that the world has decided that plants must fuel not just animals and people, but cars as well, it is perhaps not altogether surprising that food prices suddenly spiked. The New York Times quoted FAO’s Jacques Diouf last December saying that in an “unforeseen and unprecedented” shift, the world food supply is dwindling rapidly and food prices are soaring to historic levels. The price of wheat increased 130% in the past year, that of soybeans almost 90% and that of rice more than 70%. Josette Sheeran, Executive Director of the World Food Program was quoted thus: “We’re concerned that we are facing the perfect storm for the world’s hungry.” Her agency’s food procurement costs had increased to the point that poor people are being “priced out of the food market.” There is a very real food crisis and it weighs most heavily on the poorest countries. There have been food riots around the world. The prices of basic grains has come down a bit in recent months, but they remain at levels that mean that people in the poorest countries not only eat less, but turn to less nutritious diets. Is there a quick solution? Probably not. This is definitely not a crisis of the sort that can be addressed simply through a transient increase in food aid. It is the coming reality for a world increasingly limited in natural resources and water facing a changing climate and a growing population. So what stands in the way of another Green Revolution? There are parts of the world that are, by now, two scientific generations behind the leading edge in agriculture. Let me show you how dramatically we have transformed our food plants first over millennia and more recently over the past century. Maize (also known as corn) came from this grassy relative, called teosinte. Corn and teosinte are so different that they were originally assigned to different species. Over many thousands of years, people have converted this grass to one of humankind’s three staple grains. And yet these two plants are so closely related that they can be crossed and the off-spring are everything from what looks like teosinte seeds to small and medium-sized ears of what is recognizably corn. Teosinte seeds are produced at the top of the plant, like those of other grasses and are inedible. In fact, they have silica deposits in their surface layers – they’re hard as rock. About 10,000 years ago, people collected a few mutations that converted teosinte into the precursor of the modern corn plant, with soft seeds carried on this telescoped side shoot we call an ear. The truly dramatic expansion of the ear took place largely during the 20th century, when it was discovered that seeds from a cross between two highly inbred, rather small and weak plants gave much more vigorous plants with much bigger ears in the first generation. This is called hybrid vigor and is the basis of our current extraordinarily productive hybrid corn varieties. These were introduced in the U. S. during the 1930s, facing a good deal of the kinds of resistance that current biotech crops are now facing. Today hybrid corn is widely grown around the world, but not in many parts of Africa. We’ve done the same with wheat (parenthetically, wheat is a hybrid between 3 different species) and rice. Here are some examples of what we’ve done to transform plant seed structures into human foods. This juicy, huge tomato’s precursor was a tiny, toxic seed pod. Seedless fruits, of course, are crippled in their ability to reproduce, since seeds are the plant’s reproductive structures, and are today produced entirely by cloning, generally by a procedure in which shoots are grafted to hardy roots, sometimes even of a different kind of plant. During the 20th century we added some new methods that allowed breeders to speed up the processes of genetic change that are inherent in all organisms. In particular, they used certain chemicals and radiation to increase the rate of mutation, that is, genetic change. For example, one favorite variety of very red grapefruit – the Texas Rio Red grapefruit – was created by irradiating seedlings from Texas at the Brookhaven National Laboratory on Long Island, then sending them back to Texas to be grown and examined for desirable mutations – one of the mutations produced this redder, more healthful fruit that’s such a favorite at Christmas time. By the end of the century, up to half of new crop plant varieties released had a chemical or radiation mutagenesis step in their derivation. In the 1960s, we embarked on a genetic revolution that has permitted the development of a new set of methods for modifying plants in ways that are useful to people. Research in the 1950s and 1960s identified the existence of tiny chromosomes in bacteria that could replicate themselves independently -- these are called plasmids. Other discoveries led to the identification of proteins, called restriction enzymes, that could cut these little chromosomes in a way that made it possible to insert a piece of genetic material, the DNA, from a completely different organism, then reseal the plasmid. So, for example, the green part of this circle could be a piece of DNA from a plant or an animal and the resealed plasmid is then called a “recombinant” plasmid. This new recombinant plasmid can be slipped back into the bacterium, where it replicates itself many times over, even as the bacteria multiply. But before they begin to multiply, the bacteria are spread in a very thin film on a agar-filled dish so that each bacterium grows separately into a colony. Each of these small dots on this Petri dish consists of millions of bacteria derived from one single bacterium that received one single recombinant plasmid. The bacterium has copied the same piece of DNA many times over, making enough copies so that the DNA can be analyzed at the chemical level to determine its informational content. DNA is a long, skinny molecule that encodes the information needed to make protein – the linear sequence of the 4 building blocks of the DNA molecular specifies the sequence of a protein. Proteins, in turn, are the basic building blocks and powerhouses of organisms. The basic techniques of cloning and sequencing DNA underlie today’s genomic revolution, in which scientists have determined the genetic information of literally hundreds of different organisms, from viruses and bacteria up to plants and animals and humans. There’s one more player in the modern plant breeder’s toolkit for modifying plants. That player is a soil bacterium called Agrobacterium tumefasciens -- its nature’s genetic engineer. This video clip shows how the bacteria are able to transfer genes into plants. Wounded plant cells – in the video clip its roots -- send out chemical signals the bacteria detect and move toward. They then transfer a piece of DNA from a plasmid they carry to the plant cell, where it integrates into the chromosomes of the plant and are then expressed to promote the formation of a tumor. Interestingly, the genes the bacterium inserts into the plant also stimulate the production of compounds, called opines, which nearby bacteria use as food. What scientists have done is to remove the pathogenic genes that cause the tumor and used the transfer mechanism to carry genes they wish to add to the plant. Here’s how it looks in the laboratory. Leaves are cut into pieces to stimulate the release of the wound compounds, dipped into a suspension of Agrobacterium carrying a gene to be added to the plant, and then put on a medium that will allow only those cells that are carrying the new genes to grow under the influence of hormones in the medium. This allows the cells to grow into a lump called a callus. When the growth-promoting compounds are removed from the medium, the cells do something magical -- they develop into a plant. The plant is exactly the same as the plant from which the leaf was taken, but it now carries a new gene and is called a transgenic plant. Now I will show you some of the crop modifications that have been achieved using these methods. Here’s the kind of damage corn borers do to corn -- this is one of the most damaging of corn pests. This is an ear of corn on a transgenic plant carrying a bacterial gene that codes for a protein that is toxic to the larvae of the plant pest, but not to animals or people. It’s called Bt because the gene comes from another soil bacterium, Bacillus thuringiensis, which has long been used as a biological pesticide and is popular with organic farmers. Genes from the same bacterial family have been used to protect cotton from the devastating cotton bollworm. Here’s an example of a very different kind of biological protection from a virus disease. This is the damage that papaya ringspot virus does to papaya fruits; this is a healthy plant and this is a sick one. Here’s the virus and its insect vector. This is virtually impossible to control in the long run and was threatening to destroy the papaya industry in Hawaii in the early 90s. Here’s the damage to trees and here are resistant trees. These transgenic plants express just a tiny segment of the viral genetic material, which is enough to trigger the destruction of a new invading virus injected by an insect. This remarkable system of protection is based on a very old observation that plants become immune to viruses once they’ve been exposed to them, much like people. But plants don’t have an immune system and the mechanism is different at the molecular level, yet it’s very effective. Resistant papayas saved the Hawaiian papaya industry and are currently being developed for the Phillipines. GM crop acreage has increased rapidly world-wide, driven primarily by cotton, corn and soybeans. The 2007 global acreage planted in GM crops was 114.3 million hectares. Better yet, the adverse effects, such as rapid development of Bt resistance, have not materialized. The only unexpected effects have been beneficial. For example, many grains and nuts, including peanuts, are often contaminated by toxic compounds, called mycotoxins, made by fungi that follow boring insects into the plants. Two of these, fumonisins and aflatoxin, are extremely toxic to people and animals. Bt corn, however, shows as much as a 90% reduction in mycotoxin levels because the fungi that follow the boring insects into the plants can’t get in. No insect holes, no fungi, no mycotoxin. Better yet, it appears that planting Bt crops might well reduce insect pressure in other crops growing nearby. Bt cotton has been widely planted in Asia. Analysis of the population dynamics of the target pest, the cotton bollworm, showed that Bt cotton not only controls the target pest, cotton bollworm, on transgenic cotton designed to resist this pest but also reduces its presence on other host crops and decreases the need for insecticide sprays in general (Science 19 September 2008). Strikingly, among the 23 countries growing GM crops, half are less developed countries. More importantly, 11 of the 12 million farmers growing biotech crops are small-holder, resource poor farmers. The simple reasons that farmers migrate to GM crops is that their yields increase 5-25% and their costs decrease, in some cases by as much as 50%. The estimated cumulative increase in farmer income over the 12 years since GM crops began to be used is on the order of 35 billion US dollars. There are environmental benefits, as well. Herbicide tolerant crops contribute significantly to soil conservation because more farmers farm without ever plowing their land – this is called no-till farming. A second benefit has been the concomitant reduced fuel use because of tilling takes tractors and fuel. Thus herbicide tolerant crops have two environmental benefits: soil conservation and reduced CO2 emissions. Both people and wildlife benefit from insect-resistant crops. Pesticides are applied quite safely in the highly mechanized agriculture of developed nations using climate-controlled tractors, but there are some 25 million cases of pesticide poisoning every year in less developed countries where farmers often have little protection from it. Moreover, pesticides kill a broad spectrum of insects, both harmful and beneficial. In just 12 years since their initial introduction, insect resistant GM cotton and corn have reduced the amount of pesticide used by almost 290,000 metric tons of active ingredient. That translates into is more insects and more wildlife, such as birds, which can thrive along with crops. In China, farmers growing GM rice reduced their pesticide use by nearly 80 per cent and more than half of them used no pesticide at all. More than 10% of farmers growing conventional rice showed symptoms of pesticide poisoning, while none of the farmers growing Bt-resistant rice did. So now I’ve told you that there are environmental benefits to using GM crops, as well as benefits to people from reduced pesticide use. But are GM foods safe to eat? What makes them either more or less safe than food crops produced by radiation or chemical mutagenesis – or even by traditional breeding? Let’s start at the simplest level: what’s being added by these procedures I described and are these things safe? What’s added is a gene or a bit of DNA. Do plants contain DNA? Yes. DNA is the stuff that genes and chromosomes are made of and they’re what makes a plant a plant and a human being a human being. You’ve been eating the DNA of plants and animals all your life, cooked and raw – although I have to tell you I’ve been asked more than once whether plants have DNA. The amount of DNA that’s added is about a billionth or so of what’s already there. You break down DNA starting in your mouth and by the time digestion’s done, it’s pretty much broken down into its nourishing constituents. Now most genes encode – that is, contain the instructions for – assembling a protein. Proteins are the nourishing things you eat in meat, milk and eggs – these are really rich in proteins. But the plants you eat contain proteins, too, although the parts of plants we tend to use – the seeds of wheat and rice, the kernels of corn – are rather rich in starches and sugars – and sometimes oils, too. That’s why we grow them. Now most of the thousands of proteins you eat are perfectly harmless, but a few, like one of the proteins in peanuts, cause allergic responses in some people. And there are a few proteins that are toxic to people and animals. So before a protein-coding gene is added to a plant to make a GM crop plant, the protein must be subjected to tests for toxicity and allergenicity. Now this has never been done before in the history of agriculture – testing for whether a new protein in the food supply is either toxic or allergenic! We had to find out the hard way. Peanuts are a relatively recent addition to the American diet and kiwi fruits and even more recent addition – the incidence of allergies to both is quite high. No allergic responses have been detected to GM crops. So the answer to this question is a simple YES. In fact, because of the extensive prior testing, I submit to you that GM crops are the safest we’ve ever introduced into the food chain. Besides food safety, perhaps the most frequently expressed concern about GM crops is whether they’re safe for the environment. That seems to mean different things to different people. I think that I’ve already addressed one aspect of this question: controlling pests with insect resistant plants is better for the environment from the perspective that pesticides are non-specific and kill all kinds of insects, while insect-resistant crops affect only those insects that attack the crops. Less pesticide is better for the environment – more insects, more birds and so forth. Less cultivation in the case of herbicide tolerant plants reduces CO2 emissions and soil erosion. But often what people have in mind when they question the safety of GM crops is whether the genes that are added to them will somehow escape and create superweeds or perhaps invasive species. Well, here I think one needs to use a bit of common sense. For the most part, crop plants are plants that people have crippled in their ability to survive in the wild and adding one gene that codes for a well-characterized protein to a familiar crop gives you the sum of the two: your familiar crop plant with one extra gene. If the plant wasn’t invasive or weedy to begin with, adding one gene will not make it weedy. People also talk about something called gene “flow” – the escape of genes. Genes move only through pollen or seeds – they don’t move on their own. And they only move to close relatives – other varieties in nearby fields. So this is mostly a management problem for farmers and it isn’t a new one. So…. a farmer has to know not to plant his sweet corn too close to his fodder corn, or he’ll have fodder kernels among the sweet. Spreading genes from crop plants into wild plants happens only if there are closely related weeds nearby, it’s happened since people domesticated plants, and it is generally not a problem, since the traits that people value in food crops don’t help plants to survive in the wild. People have worried about this a lot, but studies so far say it actually doesn’t happen much in the field, even when it can be done in the laboratory. So the answer is YES. But will GM crops reduce biodiversity. Human agriculture itself is, other than building roads and cities, the most destructive thing we do to biodiversity, stripping the land and planting one crop. As the food needs of the human population continue to grow, the very most important thing that we can do is to increase our agricultural productivity on the land we already farm in order to preserve what wildlands we have left, particularly tropical forests which are extraordinarily rich in biodiversity. So the answer is NO and in fact, GM crops can help us preserve biodiversity by reducing our use of toxic chemicals in agriculture and perhaps in time, increase the efficiency with which plants use nitrogen fertilizers and solar energy. The world is indeed moving ahead with the introduction of GM crops. India has witnessed the extremely rapid adoption of Bt cotton and is expecting a further 5% increase in its cotton crop over last year because of it. India is moving to commercialize Bt eggplant and Bt rice in advanced stages of testing in China, India and the Philippines. China has recently announced a 3.5 billion dollar investment in agricultural biotechnology research. The bad news is that well-meaning people around the world still believe that GM crops are dangerous, their beliefs fueled by misinformation – even disinformation – on the Internet, from public interest groups and the communications media. Although some European countries, particularly Spain, are growing GM crops, much of Europe, Japan, and most of Africa remain adamantly opposed to crops improved using molecular techniques. These persistent perceptions that GM crops are dangerous and unhealthful have resulted in restrictive and costly regulation of such crops – even banning of both their use and even to their import as food aid. Perhaps the most unfortunate consequence of such attitudes occurred in 2002. With almost 3 million people at risk of starvation as the result of drought, President Mwanawasa of Zambia refused to accept shipments of corn from the U.S. because he could not be sure that it was GM-free. I wish I could tell you that this was an aberration, an idiosyncrasy of one leader. But it is not. As Professor Robert Paarlberg explains in his new book titled “Starved for Science: How Biotechnology is Being Kept Out of Africa,” Europe’s anti-GMO beliefs are in some sense forced on Africa through a variety of mechanisms, ranging from the funding of anti-GM NGOs, such as Greenpeace to threats of trade embargoes. For example, Paarlberg relates that in 2002, with drought in Zambia creating a dire need for international food aid, Agriflora, a private company in Lusaka, Zambia that produces vegetables for export to the UK received phone calls from UK supermarkets that their exports of organic baby corn would be in jeopardy if food aid shipments containing GM maize were allowed into Zambia. Agriflora and other export-oriented growers asked President Mwanawasa to reject the food aid. He did. His advisors later confirmed that exports were a concern, citing “a potential risk of GM maize affecting the export of baby corn and honey in particular and organic foods in general to the European Union if planted.” (Paarlberg, p 136). This is a dramatic story, but not a unique one. Today, there is still only one country in Sub-Saharan Africa that grows GM crops on a commercial scale. So how important are these molecular techniques we call GM to achieving food security in the world? They are an important part of future food security, but only a part of it. There are large parts of the world that in which agriculture has not yet benefitted from science, much less the most up-to-date molecular science. Many of the world’s poorest people are rural, small-holder farmers, still farming the same way their ancestors did a hundred years ago, virtually untouched by modern agriculture. Land-holdings are small and, as you can see from these pictures of Rwanda, farmers plant many different crops on each small plot – some bananas, some coffee trees, some corn and other vegetables. Farmers take what they grow to open air markets and what isn’t sold and used right away, rots. There is virtually no food processing industry and no cold storage. Today we hear talk of a second Green Revolution, but expanding the food supply today in the poorest, most crowded, and insecure nations is no easy task. The next slide is my only wordy slide and it lists the many challenges that must be met in less developed countries to increase food security and to make it agriculture a viable source of income. There’s plenty of room for increasing productivity – the benefits of good seed, including hybrid corn seed, and fertilizer have not been realized in many countries. After Malawi experienced a famine in 2005, its president decided to defy the international donor community and subsidize seeds and fertilizer. The results were stunning: within two years, Malawi went from being a food aid recipient to a food exporter. How will this momentum be maintained as fertilizer costs go up with energy costs? Is this a model for other countries? Hugh Grant, CEO of Monsanto, points out that it costs $400/ton to ship corn to Malawi from the US and it costs $35/ton to grow it there. Next year, even with escalating fertilizer prices, the difference may be even greater. But the good news is that the Josette Shearin announced at the recent UN General Assembly meeting in New York that the World Food Program will begin buy a billion dollars of the food it procures locally, rather than shipping it in from foreign countries. This will provide a welcome stimulus for farmers in less developed countries. Establishing a sustainable modern local agricultural economy in the poor countries of Sub-Saharan Africa and Southeast Asia demands many improvements, from roads to storage and food processing facilities, to food safety monitoring, to the reduction of regulatory and trade barriers. It can be done and there is growing recognition that all these elements have to be addressed -- simultaneously. Looking to a future that may bring a drier climate -- or perhaps just a more unpredictable one -- our most important resources are people and knowledge. Just as medical research allows us to understand and control diseases, so research on plants, plant stresses such as heat and drought, and plant pests and pathogens are absolutely essential to our ability to achieve food security on our small and crowded planet. Today -- and increasingly in the coming decades -- it will be modern molecular science that offers the knowledge and the tools to grow more food with less water and less damage to our environment. Our most advanced agricultural biotechnology companies are anticipating doubling of yields per acre in our major staple and feed crops, corns and soybeans in the coming years. This will be reached through an increasingly sophisticated use of molecular modification – what the world calls GM – and genome-based plant breeding. If the developing world is to benefit from these advances, it is important to moderate the widespread prejudice against them in the developed world. I am encouraged that China and India, both of which have their fair measures of anti-GM controversy, are steadily moving forward in using molecular modifications to improve crops. Perhaps a combination of increasing food prices and growing recognition that modern GM crops are no more dangerous than their more conventionally derived precursors will permit other countries to move forward. The unacceptable alternative is an ever-widening food security gap between the developed and the developing nations. I end with a quote from Dr. Florence Wambugu, a Kenyan plant pathologist who has devoted her life to bringing modern methods of crop improvement to Africa, starting with the development of virus resistant sweet potatoes. She says simply: “You people in the developed world are certainly free to debate the merits of genetically modified foods, but can we please eat first.” |
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