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Diplomacy in Action

Crop Biotechnology: Science and Sustainability

Peter Davies
Jefferson Science Lecture
Washington, DC
March 27, 2012


Bill Colglazier:

Well good morning everyone and welcome. My name is Bill Colglazier, the Science Technology Adviser to the Secretary, and it's my pleasure to introduce the third or fourth Jefferson Science Fellows Lectures. For those of you who are not familiar with the Jefferson Science Fellowship Program, it's a terrific program in its eighth year. It was actually started by one of my predecessors in this position. It brings tenured faculty from U.S. universities, faculty of science and technology, to come and spend a year working at the State Department barring USAID and then after their year here also to be available for five years after that to continue consulting and helping with activities here in the either USAID or the State Department.

Peter Davies is our speaker today. He's a distinguished plant physiologist. He's a professor at Cornell University where he's been for forty-two years teaching at the Department of Plant Biology and Horticulture. He holds both a bachelor and PhD from the University of Reading in the U.K., and before going to Cornell he was also at Yale University. His expertise in the field of plant development, especially plant hormones, and crop biotechnology. He's published over one-hundred papers and several books, and he's also the editor for Plant Physiology for the McGraw-Hill Encyclopedia of Science and Technology. So you can see he's truly a world class expert in his field.

At the Department of State he's been a science advisor in the area of biotechnology working in the economics bureau here at State. So it's a great pleasure to have him here today, and he's going to be speaking about crop biotechnology, science and sustainability. Peter.


Peter Davies:

So thank you very much, Bill, for that kind introduction, and I'd like to thank all the personnel in your office for looking after the Jefferson Fellows while we're here. I'd also like to thank my host office, particularly Ed Kaska and Jack Bobo, and I won't name everybody else in the office, but thanks for very much for being a great team and a very friendly group during my time here.

Okay, today I would like to take this topic of crop biotechnology and give you some of the science as to how biotech crops, as we call them, are created, look at some of their characteristics and some of their advantages, and at the end, hopefully if there's time, to take any questions that you might have.

So to start with people, tend to think that these sort of crops are relatively new, but one has to note that humans have been developing and modifying crops for hundreds of years by crossing both within a species and between species, and during this time such selective breeding has led to crops with higher yields than their wild progenitors. As an example of this we can look at modern corn on the right versus its progenitor, mainly a wild grass called teosinte which can be found in Mexico. Corn does not grow in the wild. It cannot be found in the wild. It was developed from this wild grass to what we have today solely by human activity. So what I'd like to start off doing is comparing traditional plant breeding with the modern biotech plant development. So first of all what we need to know, as has been pointed out to us in previous Jefferson lectures, characteristics of an organism are determined by the genes and the genes composed of a sequence of bases of DNA arranged in the chromosomes. What happens in traditional breeding is that you have a commercial variety -- each of these little balls represents a gene -- and you have one characteristic you would like to get in from a donor, and that's the yellow ball there in the wild plant. You cross these two, and you have a mixture in the new variety, but you have brought in the desired gene with a whole lot of undesirable characteristics. And this means there's a lot of work often many, many years to get rid of these undesirable characteristics surrounding the desired gene. What genetic engineering does is exactly what plant breeders have been doing for thousands of years, but doing it much more precisely. So the idea of genetic engineering is that you have a commercial variety, or a variety you like, and you have one extra gene you would like to put in, and what biotechnology can do is insert that gene very precisely without all the undesired characteristics. Another thing we need to note is DNA represents a set of instructions, rather like a cookbook. And it is identical for all organisms. So that it doesn't matter where this gene comes from, it will do the same thing in any organism provided that it has an “On” switch to start it off.

So this is when a normal class I turn to the class and I ask them to get out their clickers or personal response system, rather like Who Wants To Be A Millionaire. Unfortunately, the State Department hasn't got that high tech, so we're going to have to do it by a show of hands, but we've got to get some class involvement here. So the question for you is you know your character -- or at least I hope you do -- your characteristics are regulated by DNA, and so are the characteristics of a banana. So how much of your DNA do you share with a banana? And we're going to do it by a show of hands, and we're going to see how good you are at making this judgment. How many think you do not share any DNA with your banana? Okay, one percent. Show of hands, please. One. Ten percent, a few. Fifty percent, a fair number. Ninety percent, go, well, most of you would be a bit more yellow than you actually are, so it's actually -- you share fifty percent of your DNA with a banana, sorry not ninety percent, but there's quite a bit of similarity, and so we can have a conclusion from that.

All right, having now got us all on the same page with regard to DNA, let's have a look at why this topic is important. And we start off by looking -- this is the human population running from 1750 to 2050. This is -- we're just about there now, and as you can see we're at seven billion and a further increase in population is expected by 2050, and this is going to represent a considerable increase in global food demand so that in the next thirty-eight years we need to produce enough extra food to feed nine billion people. And this means that we need seventy percent more food by 2050 than we have at the present time. And so the answer to this is that we need to do targeted modification of the plants to get a higher yield and other characteristics. So, I'm going to start of by giving you a list of these characteristics rather like I trust a good sermon in church. I tell you what I'm going to tell you, then I'm going to tell you, then I'm going to tell you what I just told you. So we're going to start off with what I'm going to cover. The benefits of crop biotechnology are that we can obtain increased yields. The result of this we can -- is we can use less land, and leave more land for nature. With some crops you can do less till. That means less turning of the ground, and less soil erosion, and because of the fewer operations with tractors, you can use less fuel, and a result less carbon dioxide is emitted and less contribution to global warming. Some biotech crops have the incorporation of insect resistance, and this can decrease the use of toxic pesticides. Some more recent developed biotech crops make use of disease resistance, so you can get -- maintain the yields without spraying and with some diseases it's impossible to spray. So this is very important, particularly in developing countries. Some new crops have tolerance to drought -- I'm going to cover all of these in a bit more detail as we go -- and some newly developed crops -- they're not out yet, but they will be offering improved health and nutrition.

So before we have a look at each of these individually, I'd like to tell you how these crops developed. Oh, and before that I see we're going to have a look at how these actually have been adopted. And here are some figures for the global area of biotech crops from 1996 when the first crops came in through 2011. The green line is the total area in hectors, and these are millions of hectors. A hector is about two acres, so if you want acres, double this number. The blue line is industrial countries, and the red line is developing countries. Now, what is interesting here is that while we still have an increase in the adoption in developed countries, adoption in developing countries is the area that is actually picking up. And on this map the ones that use biotech crops are in green, and the countries that have not yet adopted this technology are in yellow. And if we look at individual crops, we can see that, again, this is global adoption rates percent. This is the millions of acres, millions of hectors. We can see that cotton is eight-two percent biotech, soybeans seventy-five percent, maize or corn, thirty-two percent and canola, which is an oil crop, twenty-six percent. So with some of these a good proportion is already biotech and in the Unites States it is even higher, particularly for maize.

So, now we will turn to how these are made. And my own university has been central to some of these developments. One important thing was discovered, or worked on over 50 years ago now, and this was a plant physiologist named F. C. Steward working at Cornell, actually another Englishmen working at Cornell. And he was able to grow a whole carrot plant, not from a seed, but from a single cell of a mature carrot. So the idea was as follows: He took a carrot. He took some cells of that, put them in a nutrient solution, manipulated the hormonal content, and the little cells started growing as if they were embryos. He then took these embryos, put them on nutrient jelly, and from that he was able to get a carrot plant, and so we have now gone around a complete lifecycle without actually having a sexual step. And this was the crucial point that enabled plant biotechnology to develop. You have to be able to develop a whole plant from a single cell.

The other thing that has to be done in plant biotechnology is to move genes. And there are two main ways of doing this, and we call this plant transformation. The first actually uses a bacterium, and the bacterium is called agrobacterium tumefaciens. In nature it causes a gall, what we call crown gall, which is a tumor disease of plants, and here you can see the crown gall -- this is somebody's hand. You get some idea of the size on a rose stem. What we don't want galls on plants that we breed, but there's some interesting facts about this. You can find tumors on plants which are free of the bacterium, and initially this was a big puzzle. How could this occur? And it turned out that a small piece of bacterial DNA with the tumor making instructions, and we call this little piece of DNA a plasmid had been incorporated into the plant's DNA. Now, when molecular biologists discovered this, they started moving genes in, but they still got the tumors. They were then able to work out which genes on the little circle of DNA represented by this little circle here. This is not to scale. Which genes caused the tumor properties which, again, turned out to be hormone-making genes. They removed those, and they were then able to put in a gene of choice. So what we do is we start off by cutting, and this is done by enzymes. I don't have time to go into it but they are able to cut the plasmid, find the DNA containing the gene for a desired trait, and cut that, put the two together, and now we have a splicing event, and so we now have the desired gene in the plasmid. And this is put back into the bacterium, and then the bacterium is put on the plant, and it does what it does in nature. It transfers some of these genes here from the plasmid into the plant cell. So you put the agrobacterium with the plant cell, it puts the genes in, so now we have this plant cell. This represents a couple of chromosomes, and there we now have the piece of DNA that we wanted put into the plant by cell, by DNA -- by the agrobacterium. And now we go through Steward's system of regenerating a plant, so we now have a plant with a new trait. So that's one method.

The second method uses a technique called microprojectile bombardment, or more colloquially, the “gene gun.” Here we have some plants facing a gun, not quite like that, but it's that idea. And here is the piece of apparatus, and what this does is actually fires gold particles -- that are coded with DNA -- into plant cells. And the DNA miraculously -- and that's what it was when it was first found -- becomes incorporated into the plant DNA. This was also developed at Cornell, and it was developed by a -- actually a strawberry breeder, and he thought up this idea, and what he initially did it with was a nail gun from a hardware store. You can go to Home Depot or Lowe's or where ever you want to go, and you can buy these nail guns, and they have little cartridges, and they normally fire a nail. Well, he modified it so it instead of firing a nail, it shot initially tungsten particles. And, the whole idea was sold to DuPont. Do we have any DuPont people here today? It was sold it to DuPont, and we wished we hadn't, because DuPont made all the money off it. [The gun] was modified to have air pressure, and here's a technician doing it. You put the particles here. The air pressure goes up. It blasts a membrane, and suddenly all these little gold particles get shot into some plant cells there. And you then go through the cell regeneration. And this is very useful, because agrobacterium does not infect all plants. It's very good for tobacco, but tobacco is not considered a desirable plant these days. So if you want to do soybean, or corn, this is a much better procedure, so this is the standard procedure for many plants that are not in infected by agrobacterium.

So very quick we're going to have a summary of this. Okay. Here's agrobacterium, so we can introduce genes using agrobacterium, or we can fire the gold particles with DNA into the same plant cells. You then get the genes incorporated, you then go through a cell replication system, plant them onto nutrient jelly, and you now have your plant modified with the new trait.

So, let's look at some of the traits that have been put into plants. I'm going to start off with insect resistance through what we call BT toxin. The background for this is that corn or maize is subject to damage by various insects. There's a corn borer eating away, and obviously, this decreases yields. But not only that, with the corn borer damaging the outer husk of the cob, fungus can get in, and here we see this black is a fungus. And this is dangerous because this -- the chemicals produced by this black fungus can be cancer causing. So that is a good reason to not want the damage, and not want potentially dangerous chemicals in there. So what was done was to take the bacterium called bacillus thuringiensis, which gives you the BT, and it produces a protein that is lethal to many insects. It does this by inhibiting digestive enzymes in the insect's gut: animals are immune to this. All other animals -- it only affects the insects that are eating the actual plant. Now, the gene for this protein was taken from the bacterium and used to transform crops, so that the tissues now contained this protein. What is interesting about this, by the way, is that this bacterium has been used for a long time to spray the whole bacterium or bacterial slurry on the plants. And if -- when this is done, the plants are regarded, or the produce of is regarded as organic. So you can get organic produce with BT bacteria already on it. However, this is a lot neater. Instead of having the whole bacterium there, you only have one protein put into the plant. And this offers season-long protection against insects that might eat the plant. Here we have regular corn. Here we have BT corn, and you can see no insect damage at all. And so we have higher yields. We have a damage-free crop, and in addition, there's no need to spray toxic insecticides to control insects.

A second example -- the BT in this example were the first ones developed -- is to improve weed control. And what we need to note is one of the biggest reducers of yield of crops are weeds that compete with the crop by shading, taking the nutrients in the soil, et cetera. So it has been for hundreds of years one of the main objectives in agriculture has been to remove weeds, done initially with a hoe, and then with a cultivation between the rows. But here's a better way to do it. This is a herbicide called glyphosate. Now, we have many herbicides, and quite a few of them are -- have selective properties. For example, the herbicide 24D can be used in wheat. It kills broadleaf weeds. It doesn't kill the wheat. But glyphosate kills everything. You can go and get it at your local hardware store to spray on your path, or your patio, if you want to remove the weeds. So the crucial thing about this was to develop crops that could resist the glyphosate. But glyphosate is a much safer herbicide than any of the older ones on the market. It's safe because it targets a process that only exists in plants. It does not exist in animals, and in addition, glyphosate breaks down very rapidly in the soil, unlike many pesticide chemicals, or herbicides that may persist for months, or even years. You can spray -- a farmer can -- or a gardener can spray glyphosate on the soil, and plant new plants into that soil the next day. One day is sufficient. So how does glyphosate work? Well, glyphosate works by inhibiting a biosynthetic process in plants. And here is a very simplified version of it. We have a precursor in basic metabolism, and it goes through many steps that I'm not detailing here. But it ends up producing a whole range of compounds that are very important to plants. Amino acids make proteins. Phenolic compounds, which are involved in defense, a natural defense of plants, and they're also flavor components. And it's also cotyledon which is important in cell walls which holds plants up. But this process only exists in plants, and what glyphosate does is block one of the enzymes in this pathway. As I've said, animals do not have this process. They do not have this enzyme, so glyphosate has no affect whatsoever on animals, a great advantage over some of the older herbicides which do have some toxic properties.

Now, how are the plants made resistant? Well, what the biotech engineers did was they found a bacterium that was resistant to glyphosate, and they took a gene from this bacterium. What [the gene] did was have an alternative pathway. So the glyphosate still works, but there were other enzymes in the bacterium that managed to get around this block in the pathway. So when these genes were moved to plants, the plants were now resistant to glyphosate. And because this was a patented chemical, named Roundup, the resulting crops were named “Roundup ready.” And it's been transferred to many plants including soybeans, corn, canola, cotton, sugar beet, and alfalfa. And these plants are unaffected by glyphosate, so you can have very, very clean crops, no competition from weeds and higher yields.

The results of both of these developments have now been combined, and it turned out to be many varieties of BT, and they target different insects. And now we have what are called stack traits. For example, there is one maize out there that has eight added genes, three BT genes for aerial pests, three BT genes that target subsoil pests, and two genes resistant -- for resistance to different herbicides enabling a rotation that prevents the build up of resistance. And this actually is sort of a combined product from more than one company, because different companies have different genes.

Next advantage of these crops I would like to look at involves disease resistance. And one of the first ones to be commercialized for this was resistance to a disease of papaya in Hawaii. And this, again, was developed by my own university by a pathologist at Cornell. And he came from Hawaii, and in Hawaii papaya is an important crop. And it was hit by a disease called papaya ring spot virus. Here's papaya before the disease and this is a Hawaiian plantation after the disease struck, and you can see how it is decimated. And so here is a little bit of detail. Here's a fruit with the ring spot. Here's the effect on the leaves. It is transmitted by a leaf hopper. And this is just a diagram of the virus, but the point I'd like to make here that a virus consists of a nucleic acid called RNA with a protein around it. And you have to have the RNA for the virus to be infectious. So what the scientist did in that is going to solve his lab is they took a gene for the coat protein only which is noninfectious, and using the gene gun they put it into papaya. And as a result rather like when you get an inoculation against the disease, the papaya became resistant to the ring spot virus, and this is the resulting disease-resistant papaya.

Now in Hawaii papaya is a luxury fruit. The [fruit] is exported. But if we go to a place like Thailand in Southeast Asia, it is a staple of the people. It's treated rather like a vegetable, and the virus struck there as well. So here is papaya in Thailand struck with the disease, and you can see it's a pretty miserable looking plant. So the Thai scientists came to Cornell, and they worked with Dr. Gonsalves to transform the local varieties of papaya, and here is the result. This is the biotech papaya in Thailand that is resistant to ring spot disease. And so this essentially rescued the local peasant farmers where this is a very important part of their diet, rescued them from losing their -- one of the main items of their food supply.

However, there were certain people around who don't like this, and once they heard that they were field trials, they arrived in this ridiculous garb, climbed over the fence there, and destroyed the field trials. Here are their activities in the capitol of Thailand. And I leave you to judge the result of that. But they managed to persuade the Thai government that this was a wicked technology, despite the benefit to all the people, and they then persuaded the Thai government not only to cease supporting this, but to destroy all the trials. And there is the Thai government acting because the Greenpeace asked them to do so, despite the fact that this now means that the local farmers have lost their disease resistant papaya. And so here's a reaction of one of the farmers. As you can see, no GMOs. However, if you walk around with him and chat to him, you will see that the high-tech farmers, and here he is with his computer, the high-tech farmers are very much in favor of this technology. And what one of our -- one of my colleagues who spent a long time in Thailand says there are some clearly some biotech papaya being grown, because the farmers grabbed some before it was all destroyed, because that was the only way they were going to see their crop. And you can see the difference here. They've got virtually nothing there, and a very healthy growth there, so he's very much in favor of growing this.

Some other products that have been developed and -- here we are for the DuPont people. Here's your high-oleic acid soybeans. And this is now, I believe, on the market. Yeah, it's available. And what the scientists have done here is change the oils that are in soybean, and they changed it to make it high in oleic acid, so it's rather more similar to olive oil, and they did this by preventing the expression of a gene that changes oleic acid to lenoleic acid. Why would you want to do that? Well, it has a higher heat stability for frying in the food industry and improves the flavor and the shelf life. So these are the sort of other things that can now be done.

But of more advantage to peoples around the world are crops with enhanced nutrition characteristics. One of these examples of one of these is called “golden rice.” Golden rice was developed in Switzerland, but is being -- I was going to say commercialized -- it is not commercialized, it is being developed for small farmers first of all in the Philippines. And why would we have this? Well, golden rice contains a vitamin A precursor which prevents blindness in developing countries. If you -- the people do not have enough vitamin A, they can develop blindness. And this doesn't have vitamin A in it, but it has the immediate precursor of vitamin A, namely, carotenoid, which is the yellow color. And human bodies can convert this to vitamin A. And so here's what it has. It has -- it is high in carotene, and you can see the word “carrot” in there. And [carotene] is the yellow color you find in corn or egg yolk. And rice plants actually synthesize carotene themselves, but they do it in the vegetative parts -- that's the leaves. They don't do it in the grain. So the grain is white. But by the addition of only two genes, the pathway was reconstituted and made to develop in the center of the grain, the part we call the endosperm technically. And these genes originally came from, well I guess you can see where they came from, they came from daffodils, but obviously, there could be some problems with that. So instead of having daffodils, they redid it and they got the genes from corn, exactly the same things, but they come from an edible plant, rather than an inedible plant. So this is now up for approval in the Philippines, and we hope within a year and a half or so that it will be made available to the farmers.

Another product that's going to be very important in the developing world is to cope with the decrease in water availability. We think that as a result of climate change, the climate experts are predicting that there's going to be twenty-seven percent less water in many of the agricultural areas of the world, and the areas that are going to be most affected by this are the areas that are in yellow or orange. You can see much of the corn belt in the Midwest, the great grain belt of Europe, and part of sub-Saharan Africa, and also the Middle East. So this is going to be crucial to agriculture in the future. So another area where biotech plants are being developed are ones that have tolerance to drought. They need less water. They don't suffer from what we call drought stress, and they continue growing under conditions where normal crops would cease growing. So here we have as you see very dry soil, and the drought tolerant corn is continuing to grow. This is two comparative rows. This is regular corn. As you can see, it's dead. The drought tolerant corn is continuing to survive. So how is this done? Well, the first thing we need to note is that one of the effects of desiccation of plant cells -- there are similar effects in this, but one of the effects is that some of the molecules inside the big molecules such as proteins, or RNA do not fold correctly. And folding, the way molecules fold is crucial to their acting in the right way. And the first drought tolerant crop to come up for approval possesses a protein that is made by a bacterium when this bacterium is exposed to cold. And it turns out that cold and drought have very similar effects preventing the proper folding of these molecules. And this protein is called a chaperone, and it causes the correct folding of RNA. And, oops, wrong chaperone. We have the correctly folded molecules in the cells, and they are thus able to withstand desiccation better or semi-desiccation better than normal crops.

Some other crops in the pipeline have enhanced nutritional characteristics for consumers. For example, high anthocyanin, that's a red pigment you get in blueberries. Put into tomatoes, that's a purple tomato. And they've also put it into oranges more recently. This was just announced this month. Both of these come out of the John Innes Institute in England. These have been tested in animal systems and also in human diet and shown to decrease the incidents, or potential incidents of heart disease. So these are health giving crops. These are not yet commercially available, but these are the sort of things that are coming in the pipeline.

So, let's look at some of the advantages of these crops. First of all we need to note that these crops increase yield. This is the insect-resistant corn, insect-resistant cotton, and these are various countries of the world, and you can see we can see significant increases in yield produced by these biotech crops. Here are the changes in corn yield in the United States-- actually in Indiana over the years. If we go back prior to the 1930's the yields were consistently low, relatively. In the 1930's hybrid corn was developed, and these have been continually increased, so we have seen constant increases there. And we're probably getting near the limit of just hybrid corn, but now with various biotech corns, we can see the yield going up even higher. And the top test yields in 2010 were producing 1,200 bushels per acre, or nineteen metric tons per hector, and if you look at the scale here, 1,200 is probably out of the roof for the State Department, or something like that. So, using the latest biotech crops we can still get continued increases in yield. This is in the U.S., but there's even more potential for developing countries. These crops need fewer herbicide and insecticide inputs. This is the decrease in herbicide use with the herbicide resistant crops. The blue is the actual decrease in herbicide use. The red is the effect on the environment, and this is because the herbicides used are safer than the ones used previously. This is 2009. This is up to 2009. This is the decrease in insecticide use. So we are -- not only do we have increased yields, we have less chemicals in the environment. We get less impact on our natural resources in the environment by having more land available because of these high yields. And here's the land that is being calculated has been saved by these biotech crops, and this is in millions of hectors that would not be available for wildlife if these biotech crops had not been adopted. In addition, as I have already pointed out, there is less soil erosion.

One of the arguments against these crops is that we don't know they're safe. However, they've been extensively examined by scientific authorities and food safety authorities in both the U.S. and Europe and other countries of the world and declared to be totally safe. They've been consumed by Americans for fifteen years with no ill effects. And there's not a single documented case of illness or allergy caused by these crops. And in addition, the environmental effects, or the possibility of invading areas surrounding are, in fact, found to be absolutely no different than conventional crops of the same species. Other objections you will see, well, they lead to the rise of super weeds. Well a super weed is not a super weed, it's just a weed that is resistant to that one particular herbicide. So, this can be solved by alternating herbicides. Super bugs, super bugs are not really super. They're just resistant to bacillus thuringiensis protein. And both of these can be prevented by good farming practices such as rotations of crops, or rotations of herbicides, and farmers are recommended to interplant a small area of non-BT crops with their BT crops in order to prevent the build up of resistance to BT. And this is helped by what we call stack traits where there are multiple traits in one particular seed line.

There are some problems and one of the problems is opposition, but it's not based on science. There has been very slow approvals in some countries. And some countries approve them, and others don't, and this has led to trade problems. Another problem is what we call the low-level presence of unapproved biotech crops in international commerce. By low-level presence I mean point one percent found in the bottom of a shipping container leading to an entire blockage of that shipping container, or sometimes entire shipment.

So, in summary, biotech crops represent innovation, a more precise method of crop improvement. They improve competitiveness of our farming industry, or farming industries anywhere, because you get higher yields with fewer inputs. And they represent sustainability, because there is less impact on the environment, decreased use of pesticide chemicals, and with decreased tillage less impact on global warming.

And, so, just some little stories to finish off, when first I started as a graduate student, Rachel Carson's book had just come out. And she pointed out the damaging effects of excessive use of pesticides on the environment. And this came out in the book "Silent Spring". And I was a pesticide student, so I -- my specialty at that time was herbicides -- and I was rather shocked when one of my professors absolutely gave a stinging criticism of this book, because I felt I was also an environmentalist. And that's the reason I support the use of these crops, because they are good for mankind, and they're good for the environment. And following that Norman Borlaug led the development of the Green Revolution, which provided crops for the world, but with the current status of the population, this is not quite enough. We now have to do more, and so we now have to make sure that we have the development of crops that benefit humanity and benefit the environment and are going to provide food into the future. And as I said, the answer, as far as I'm concerned, is that we must use all the tools at our disposal to optimize the characteristics of crop plants, and there I will finish. So, thank you for your attention.


So if there are any questions. There are two mics, one on each side. Yes, Norma.

Female Speaker:

Peter, I just have -- that was a lovely seminar. I just have a quick question. I missed how the resistance to the papaya ring disease is produced. I heard you say something about putting the protein coat --

Peter Davies:

The gene for the coat protein --

Female Speaker:

So does that mean, then, that the papaya plant has an immune system that --

Peter Davies:

Well, this, again, it was just an idea. There was at that point no basis for this, and it was rather a surprise, but they tried it as with many discoveries, they tried it and it worked. And it is now worked with several other plant diseases. Yes, it's not the same immune system as in animals. We don't have the same cells as animals. Plants do not have the same cells circulating in their blood, but if you have this protein in each cell, it produces this resistance. I don't, to my knowledge, they have not worked out the exact mechanism of this. Allen, do you know anything? I've never seen it --

Male Speaker:

I'll talk [unintelligible] later.

Peter Davies:

Okay. All right. Do you want to go, Bill, to the microphone, then, and say they want to record this?

Ben Rosenthal:

Thank you for that talk. I think you did an excellent job, by over viewing some of the biological underpinnings and addressing some of the policy implications, my name is Ben Rosenthal. I am a biologist. There were a couple of things that I, well, I'll admit myself, you mentioned that an exciting potential in biology is that genes in one place can perform the same function somewhere else. Although with the process in transformation, we don't always know that the transformation will produce the same effect, you know, in a replicate experiment. You don't know, for example, what is -- where is the gene going to go, and is it going to modify some other function, so I thought maybe you could elaborate on that a little bit.

And I would ask you, also, to think about what we know from the context of medicine and public health in terms of the evolution of resistance. You said, "Well, we can switch to another pesticide if we're selecting for resistance." But our experience in public health is that the overuse of antibiotics, for example, typically results in the loss of their utility. These biological systems kind of have a memory of to what they have previously been exposed, and we kind of give up tools, particularly when resistance is plasmid-mediated. It's just transferred. And if you could talk a little bit more about whether you think there is justification in some fears that over planting of certain resistant crops may result in the permanent loss of some of the tools currently in our toolbox

Peter Davies:

Yes, two very good questions. Yes, with regard to transforming the plants cells with these genes, there is no control as to where it goes. In addition, you've got to put [the genes] in with the on switch, which we call a promoter. So, when you hear a talk like this, it sounds miraculous. We just --we're go to the lab in the morning, and we have a biotech crop in the afternoon. No, the success rate is extremely low. So it has to be done a huge number of times. Obviously, if the gene happens to insert in the middle of an essential gene, then, the plant will not grow well, or grow properly, so there is a low success rate of getting it in, getting it in the right place, and then checking to make sure that you do not have any major losses, or adjustments. However, it has to be -- remember that the vast majority of DNA in an organism is -- does not resemble -- represent in code DNA that is encoding for proteins. It may have a regulatory function. We used to call it junk DNA. We now think it is not junk, but there's a whole lot of DNA which, for example, in humans there's a certain amount of DNA which appears to represent ancient viruses that have gotten into our DNA. So there's a lot of places you can put it with having no effect. But, it takes, in general, these big tech companies; they reckon it takes two years to do anything. And what is interesting it takes about 10 years to get it to market, because of another eight years of testing and regulatory action, and the figures I've seen, it takes these tech companies about $170 million to get a new trait to market, assuming it works, and they know what they are going to try and do.

The next question was with regard to resistance. As I pointed out resistance is to the particular herbicide or is to BT. And, yes, there are problems where farmers are not paying attention to this. They have this wonderful new crop, the high yields, and they just do the same thing again, again, and again, and they're surprised when there's a problem. And -- but there are guidelines out there that for BT they should include five to ten percent of non-BT corn, so the insects go and eat that. And the idea was to put it around the edge. Farmers weren't doing that, so what the seed sellers are now doing is mixing it in, so the farmers don't have a choice. With the multiple genes, what we call the stack traits, because there are now, in the one I gave as an example, there are six genes for BT. Each BT is slightly different, and it resistance to what one does not necessarily carry over to the other. So by having these multiples, they think there's less chance of doing it, and into this stack trait corn they put in -- they mix in five percent of non-modified seed. So, yes, the potential is there, and hopefully farmers will take note of this, and some of them have been sort of, at least vocally, slapped on the wrist for not doing it, because we need to make sure that the farming practices do not promote the development of resistance. But as with antibiotics, I think antibiotics are a worse case, but as with antibiotics we’re probably going to have to continue to try and develop new methods of control.

Male Speaker:

Peter, and you partially answered this, but I wanted to ask about the U.S. Regulatory system for what they’re looking for when they’re trying to approve a new GM crop. You indicated some of the issues in terms of time and cost, but what are the main issues that they’re looking for in the regulatory process, and also when you finish the question in a few minutes I have a gift for you --

Peter Davies:

Oh I love gifts. Okay, the regulatory process, it is rather a complicated process which I’ve said I’ve been learning since I’ve been here. That the USDA deals with the environmental potential, invasion or something like that. The EPA deals with toxicity of any pesticides, and the FDA deals with food. So the sort of thing that the FDA is going to be interested in is whether the protein in the crop produces an allergic reaction in any person that eats it. Obviously there are very simple tests. Feed it and see if there are any visible effects, but that’s at the very basic level. So there’s got to be feeding studies, protein comparison studies, studies to make sure it doesn’t become invasive in natures. Studies to make sure that any pesticide that’s put on it is not going to be harmful, that any pesticide gene in it is not going to be harmful. There’s an interesting story about the BT, again my own university. They’re paper came out claiming that it would kill the monarch butterflies. Well monarch butterflies do not eat corn. What they’ve done is they’ve taken the corn pollen, and put vast amounts of it on milkweed leaves, and then said to the caterpillars, “Here eat that.” And the caterpillars weren’t too happy which isn’t surprising. But other scientists at my own university, we have these internal, in fact the same department that went out and looked at nature, and basically very little pollen gets on the milkweed that these would be eating. But in addition it has to be noted that if you have BT there you’re not going to be spraying insecticide, and insecticide would have a far greater effect than a few grains of pollen. So it turned out to be not important, but that was something that had to be thoroughly investigated from a pesticide environmental point of view. What I think I’m going to do is I think I’m going to have to go around and visit all these agencies, and see exactly what they’re spending their time doing. So I can’t answer your question any further than that. Oh yes.

Male Speaker:

Thank you for the wonderful talk. I did have a similar question to the gentleman before me regarding regulation. I was wondering if you could speak to issues of intellectual property and patents regarding transgenic genes and the debate surrounding that in the biotechnology field.

Peter Davies:

Sure. Yes. There are two things one needs to remember here. Some [people] complain about this industry being controlled by major corporations. First of all, one needs to note that the ones that produce the biotech seed are also major producers of non-biotech seeds. So they are important seed producers in the industry. At $170 million dollars per trait it is very difficult for a small organization to carry a trait through to commercial production. One of the reasons for this is the extremely heavy hand of the regulations and the testing that has been imposed as a result of the actions by various groups. So in placing these extreme demands they have made it very difficult for any university or small business to produce a biotech crop, and that is why we find that it is the major companies that are doing most of the production. Now we come to patents. If you do not have patents a commercial company cannot afford to invest money in producing these products. We accept patents in engineering. We accept patents in pharmaceuticals, and therefore it is reasonable that any commercial company receives a return for the extensive investment made. And this is not odorous, because if it was odorous, you would not see the adoption of these crops, but as you saw the adoption is going up, and up, and up. And the basic reason for this is that the profits that farmers can make exceed the cost of the seed, and usually by a considerable amount, because farmers are all business persons. So I think it’s quite a reasonable thing; however it needs to be pointed out that “golden rice” and drought-resistant maize is going to be released to subsistence or small farmers without cost. If indeed these farmers for example the drought-resistant maize start producing it commercially then it is reasonable that they pay a fair price for the seed. It also needs to be noted that hybrid corn is only produced by big seed companies. A farmer cannot save the seed, because if you do the yield goes down, because it’s no longer hybrid. And so hybrid corn companies produce the hybrid corn, and they sell it at a premium, but if you look at the corn growers in the United States probably 99.99 percent grow hybrid corn. Because the yields are double what you would get if you grew non-hybrid corn. So there’s also a precedent for this outside the biotech crops. I hope that covered your questions okay.

Male Speaker:

Yes thank you.

Peter Davies:

Okay. I believe.

Female Speaker:

Could I ask a question please?

Peter Davies:

Oh yes. Sure.

Female Speaker:

I’ll try to make it quick. I believe one of the earlier slides you showed was talking about the use of biotechnology crops around the world, and Europe was one of the areas that I don’t think the rate had increased in your slide. And I’m wondering how you would address the issues that people like the Greenpeace people have that destroyed the field trials about the papayas. How would you go about getting the buy in from the non-technological people? The ones that are on the ground. That are dealing with the, have issues with the genetically modified crops. There’s the technology aspect of it, and there’s also the social and political aspect of it, and how would you go about trying to get those people to buy into the advantages of the biotech crops?

Peter Davies:

This is one of the very difficult aspects of this. In general I feel that people in countries that do not want this have been made afraid of the technology, and this is largely because they don’t understand it, and there are various [groups] that are working hard to keep them afraid of it. And really I don’t understand the reason for this. My colleague does have a suggestion, but I will not publicize that suggestion further. But what is interesting is that, I don’t know if we have any representatives from [these groups] here, but one of the main one’s in Greenpeace. Greenpeace is started off as saving the whales which I thought was a good objective, and also protesting nuclear weapons tests. I thought that was a good objective. I was a member of Greenpeace, but since they have changed their focus to oppose these biotech crops the original founder of Greenpeace resigned from the organization, and I also resigned some 15 years ago as a protest over this. The people in Europe in general don’t need it, because they have a high enough yield of their agriculture for the European population. So they can get away without it. The tragedy is that there are many for example African countries that look to Europe for leadership, and Africa does need to get severe increases in its yields to cope with its population. Particularly in light of the changing climate, and they are influenced by the decisions in Europe, and this is very unfortunate. So that is the main effect of the European attitudes, but there are some countries I found the farmers very receptive when I was over there. I was over in Spain and Portugal, and they are just clamoring in Spain for drought tolerant maize, because the weather has been getting a lot drier in the Iberian peninsula. In general we find the farmers are for it, but it is the politicians who are against is, and when you speak to them they say, “Oh we know the science is correct, but we have to do it for political reasons.” And that’s what it is I think. So Bill.

Bill Colglazier:

Very well. We thank Peter. I’ve had to give a couple talks recently to people from the defense department. What I found after my talk, I was kind of surprised I came to, the host came to shake my hand and when they shook my hand there was some piece of metal in it. They, most of the offices in the defense department have these little medals they produce that distinguishes each one, but one of Peter’s colleagues, a Jefferson Science Fellow thought that Jefferson Science Fellows needed exactly the same sort of emblem. So I want to shake his hand, and present him with the --

Peter Davies:

Thank you.

Bill Colglazier:

A giant piece of metal which all of the other Jefferson Fellows can come and collect theirs.


It is one giant emblem of Thomas Jefferson, and the Jefferson Fellow who thought of this idea will remain nameless temporarily, but he’ll expose himself when everyone else comes to get theirs. But thank you all for coming, and thank Peter again for a great talk.


Peter Davies:

Thank you. Thank you very much Bill.

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