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  • Hello, my name is Pam Ronald.

  • Thank you for joining me today with iBioSeminars.

  • Today I'm going to talk about one of the most important issues of our time.

  • To introduce you to the subject, I'd like to start with a short video that was put together

  • by the University of Minnesota's Institute for the Environment.

  • How do we feed the world without destroying it?

  • This is the question that my husband, Raoul Adamchak, and I

  • have been discussing for many years.

  • Raoul is an organic farmer. Here he is at the UC Davis Student Farm,

  • talking to his students.

  • He's been an organic farmer for 30 years, and we've had quite an opportunity

  • to talk about these issues together.

  • Some people believe that organic farmers and plant geneticists

  • represent opposite ends of the agricultural industry,

  • and some people think we might even not be able to talk to each other.

  • But, we can. And that's because we have the same goal --

  • how to create an ecologically-based agricultural system.

  • Still, many of our friends and family have asked us

  • if organic agriculture is enough to feed the world.

  • And they've also asked us, "Are genetically engineered crops

  • safe to eat and safe for the environment?"

  • So, in order to answer these questions, Raoul and I recently wrote a book together.

  • And, in the book, what we tried to do is to introduce the reader

  • to what an organic farmer actually does

  • and what a plant geneticist actually does.

  • So, we take the reader through some events of our days

  • and answer questions that come up on the topics of farming and food.

  • So, the first step was to establish criteria for more sustainable agriculture.

  • And, a sustainable agriculture rests on three pillars: social, economic, and environmental.

  • For social, it's important that communities have local food security,

  • and they must have access to abundant, safe, and nutritious food.

  • In order for an agriculture to be sustainable, the farmer must be able to sell their crops,

  • and the communities must be economically viable.

  • The food that's produced must be affordable to community members.

  • Environmental aspects are critically important, and one of the

  • goals of sustainable agriculture is to reduce harm to the environment,

  • reduce energy use, reduce soil erosion, and foster self-fertility.

  • We also want to minimize use of land and water, and this is very important

  • because today we have 4-fold reduced access to water,

  • compared to individuals 50 years ago, and we have very little arable land

  • left to farm on the planet.

  • It's also important that crop systems be genetically diverse,

  • both to reduce the possibility of disease outbreaks and also to foster beneficial insects.

  • Now, the USDA National Organic Program Standards really evolved in response

  • to the environmental aspects of conventional agricultural systems.

  • And I wanted to give you a couple examples of the power of farming practices

  • to achieve a sustainable agriculture.

  • So, organic agriculture uses fewer pesticides than many conventional systems,

  • and one of the reasons is that the National Organic Program Standards

  • prohibit the use of synthetic pesticides.

  • This is my husband's farm at the UC Davis campus,

  • and you can see that he also uses a strategy of genetic diversity.

  • So, they plant many different types of crops,

  • and this will reduce harm from pests and disease.

  • Organic farms are 2x as energy efficient, and they have improved soil fertility,

  • primarily through the use of the addition of compost and crop rotation.

  • And as I mentioned, this genetic diversity also enhances microbial and insect diversity,

  • which is important to maintain these non-harmful insects in the field

  • because these insects will actually prey on pests that can harm the crops.

  • So, with all these benefits, many people ask,

  • "Is organic agriculture enough to feed the world?"

  • "Can we rest with the USDA National Organic Program Standards,

  • or are there reasons that we need to look towards the future?"

  • Now, organic agriculture, like all agricultural systems,

  • have problems with pests, diseases, and stresses.

  • And many of these are very difficult to control using organic methods.

  • Some pesticides used by organic farmers are not sustainable, in the sense that

  • even though they're not synthetic, some of these pesticides are highly toxic

  • to animals in the environment.

  • Although the yields of an organic farm really depend on the farmer,

  • the crop, the particular year... so it's difficult to generalize

  • about the yield of organic agriculture,

  • studies have shown that the yield is 45-100% of conventional systems,

  • depending on the particular crop and farmer and year.

  • Organic food is often more expensive than conventionally grown food,

  • and this can be a problem for low-income consumers.

  • So, I want to talk about the power of improved seed and discuss

  • whether modern genetic approaches can contribute to a sustainable agriculture.

  • In this slide, I wanted to give you a short history of agriculture and plant breeding.

  • It's estimated that 10,000 years ago, the first primitive domestication was carried out,

  • in wheat, rice, and corn. A few thousand years later,

  • the first grafting was carried out in 100 BC. Grafting is mixing two different species

  • onto one plant, so it's the first example of biotechnology.

  • Then, we can see, over the last 400 years, there have been many different advances

  • in plant genetics. So, for example, Gregor Mendel discovered the law of heredity

  • in 1866. In 1876, the first intergeneric crosses were carried out.

  • That is two very different species -- wheat and rye --

  • were combined to develop new varieties,

  • We also saw the beginning of mutation breeding. So what mutation breeding

  • is, and we still use it today, is you take a random chemical mutagen...

  • You take a chemical mutagen or radiation... you randomly mutagenize the entire genome.

  • So what that means is you're introducing changes to those genes.

  • And then, what a breeder will do is he'll sort through a lot of those seeds,

  • and then pick out those that have traits of interest.

  • So there won't be any information about the genes that have been changed,

  • but just that there's a new trait.

  • The first recombinant DNA molecule was discovered in 1973.

  • And the first genetically engineered crop was engineered in 1993.

  • So, since that time, we've seen a vast growth

  • in the development of genetically-engineered crops

  • and, in fact, in 2005, farmers planted a billion acres of genetically-engineered crops.

  • And today, I think the cumulative is about 2 billion acres.

  • So, what is this plant breeding? And just to give you an idea of how dramatically

  • the plants that we eat today have changed from those of our ancestors,

  • I show you here teosinte corn on top, and this is the progenitor of modern-day corn.

  • And the progenitor corn, you have to take a hammer to break it open to release the kernels.

  • Through a long process of breeding initiated by Native Americans 8,000 years ago,

  • today we have modern corn, which yields hundreds, if not thousands, more grains per plant.

  • So this shows you the dramatic power of genetics,

  • using conventional plant breeding approaches.

  • This is another example of plant breeding over the ages.

  • These are versions of a single crop species... these are Brassica species.

  • And these were developed in Europe over the last 800 years.

  • So, you can see that plant geneticists have used conventional breeding

  • to generate dramatically different plants, and of course,

  • some of us prefer some of these vegetables over others.

  • So, what is genetic engineering, and what is precision breeding,

  • and how does it differ from conventional breeding?

  • And I want to mention that precision breeding is also called marker-assisted breeding,

  • and it's also a modern genetic approach.

  • So, with conventional breedings, what I've shown here are, you can imagine two parents,

  • one in orange, one in red... They each have their own set of genes.

  • And what breeders have done over the years is, they will take the pollen from one plant,

  • put it on another and essentially by doing that,

  • they're mixing all the genes of the two different varieties.

  • And they end up with a progeny that is a mixture of the two parental genomes.

  • So, in this case, many uncharacterized genes are mixed together,

  • and then what breeders will do is they will carry out additional breeding experiments

  • to try to get rid of unwanted genes.

  • Now, one important aspect of conventional breeding

  • is that gene transfer is limited to closely related species.

  • In contrast, with genetic engineering or precision breeding,

  • one to few well-characterized genes are introduced.

  • So, in this case, you can take, for example, one variety,

  • and you can simply add a gene of interest.

  • And, with genetic engineering, this gene can come from any species...

  • so that's a big difference between conventional breeding.

  • Finally, what you end up with is a new variety that has one gene introduced.

  • So it's a very precise introduction of a single gene.

  • So, one big question is ... It's necessary that anything we eat

  • is safe to eat and safe for the environment.

  • And so this has been a subject of study or the National Academy of Sciences

  • in the United States as well as 15 other countries around the world.

  • And there's a very useful report that can be looked at

  • called the Safety of Genetically Engineered Foods.

  • So, this is one of several reports that have been put out

  • by the National Academy of Sciences.

  • What we can say is that after planting of 2 billion acres of genetically engineered crops,

  • there hasn't been a single case of adverse health or environmental impacts.

  • And this is really important to remember,

  • because any time we introduce a new plant variety,

  • whether it's genetically engineered or developed through conventional breeding,

  • there is always some risk of unintended consequences.

  • But, importantly, the method of introducing genes through genetic engineering

  • presents similar risk to the methods of introducing genes

  • by conventional approaches of breeding.

  • So, it's not the method of introducing genes that's critical, but it's the product.

  • What is the variety that's being developed?

  • And, who do those varieties benefit?

  • So, because of the importance of looking at the new variety that's developed,

  • all new crops must be considered on a case-by-case basis.

  • So, we cannot simply say that genetic engineering is all beneficial or all harmful.

  • We really need to look at the crops developed through this technique.

  • So, let me give you an example of one genetically engineered crop

  • that was developed over several years.

  • This is a papaya that's infected with papaya ringspot virus.

  • Plants get viral diseases, as humans get viral diseases.

  • And this was a particularly devastating disease.

  • In the 1950s, the entire papaya crop on the island of Oahu

  • was destroyed by papaya ringspot virus.

  • And this is devastating to those local farmers as well as to Californians

  • because we get most of our papaya from Hawaii.

  • So, growers there had no choice but to move their farms.

  • There was no conventional way to control this disease.

  • There was no organic method to control this disease.

  • So, they moved their farm to the island of Hawaii.

  • But, in 1992, the same virus was discovered in Hawaii,

  • and the papaya industry was facing the complete destruction of their industry.

  • By 1995, the production had plummeted, but at the same time, Dennis Gonsalves,

  • a local Hawaiian, had been interested in these new techniques of genetic engineering,

  • and he had been working for several years to try to develop a papaya

  • that was resistant to this particular disease.

  • So, what he did was he took a snippet of DNA from a mild strain of the virus

  • and inserted it into the papaya genome.

  • So, you can imagine this is similar to human vaccination against a terrible disease.

  • Although mechanistically it's different, conceptually it's the same concept,

  • where the plant or the human is inoculated with a mild strain of the virus.

  • So, this was very successful. The papaya plant was highly resistant to infection.

  • And, I wanted to show you some data from Dennis Gonsalves and his colleagues

  • some field experiments.

  • And this is a papaya farm in Hawaii.

  • In the center here, you can see the genetically engineered papaya,

  • and on the outside is the conventionally grown papaya.

  • This is a natural field infection. So, you can see what a dramatic difference there is

  • between the genetically engineered papaya and the conventionally grown papaya.

  • And there was a remarkable comeback of the industry.

  • You can see here, the first arrow, when the virus was first discovered on the island of Hawaii,

  • the production plummeted, and after introduction of the genetically engineered papaya,

  • you can see that production started to climb again.

  • So, today, virtually all the papaya that we eat here in California

  • is genetically engineered, and there's still no other efficient method to control this disease.

  • There's no organic method and there's no conventional means of control.

  • So, this is an example where genetic engineering was the most appropriate technology to

  • confront this particular disease.

  • I wanted to give you a second example.

  • This is the example of Bt cotton.

  • What I'm showing you here is the cotton bollworm,

  • which is an insect coming out of a cotton boll.

  • Now, this insect is a very serious pest of cotton in the United States and

  • all over the world.

  • It's estimated that in the United States, that 25% of all the insecticides we use

  • are used to control this insect.

  • Half of those pesticides that are used are considered to be carcinogenic

  • or potentially carcinogenic.

  • So, clearly a better method was needed to control this disease.

  • What geneticists did was they decided to take advantage of

  • a protein called Bt, which has been used by organic farmers

  • to control this disease by spraying it on their crops.

  • So, organic farmers generally take a bacteria that produces this protein,

  • and they can purchase vats of this bacteria that have been dried

  • and ground up, and they can spray it on their crops.

  • So, what geneticists did was to take the gene encoding this protein

  • and insert it directly into cotton.

  • And we've had several years now to look at the efficacy of this approach.

  • So, in Arizona, this is a farmer in his field, and recent studies have shown

  • that Bt cotton fields use half the insecticide, compared to their neighbors

  • growing conventional cotton, and importantly, they achieve the same yield,

  • and they see increased insect biodiversity.

  • So, these are non-pest insects, which are important because you want to maintain

  • those non-pest insects because they'll prey upon the pests.

  • And this insect biodiversity is measured by ant and beetle species abundance.

  • This genetically-engineered cotton has been grown in India as well,

  • and cotton farmers in India see approximately a 37% increase in yield.

  • And the reason for this dramatic increase in yield is that,

  • in many of these farms in India, farmers cannot afford insecticides,

  • and so they lose their crop to this pest.

  • And of course, they are seeing a massive reduction in insecticide.

  • And importantly, recent studies have shown that the profits that farmers are seeing

  • are benefitting entire villages.

  • In China, within a few years after introduction of Bt cotton,

  • total insecticide use fell by 156 million pounds.

  • And to give you an idea of this number... what it means...