20.8: Guest Lecturer

Guest Lecturer: Peggy G. Lemaux, PhD

Do We Need Genetically Modified Foods to Feed the World?

A Scientific Perspective

My focus and my area of expertise is that of a practicing scientist—one involved in the genetic engineering of cereal crops and in trying to improve the nutritional quality of sorghum. So my interests in the application of biotechnology are practical—can the technology be used to improve agriculture, and can it improve the lot of the world’s poor?

I’m not a governmental official; I’m not an economist; I’m a scientist. What can I do? Of course, the answer as to whether I can make a contribution to agricultural productivity in the developed and developing world depends only in part on the technology. The answer goes far beyond science.

Many forces limit the application of biotechnology in developed countries. We have invented techniques for inserting genes responsible for valuable traits in most crop plants. Major factors affecting the use of genetically engineered crops in developed countries include intellectual property issues, regulatory costs, economic incentives and, in my opinion, the limited ability of the public sector to directly contribute to the development of engineered crops that can be grown in fields by farmers.

The application of biotechnology in developing countries has some of the same limitations, but includes others, such as inadequate infrastructure, unique political and economic hurdles, and societal issues. And, as I can personally attest, lack of funding for scientists and economists to participate effectively. I don’t think it is possible to focus on scientific challenges alone without a consideration of the other issues, particularly in developing countries.

In 2001, the United Nations released a report called, Making New Technologies Work for Human Development. The report provided an analysis of the potential of biotech and information and communications technology for developing countries. Summarizing his thoughts on this topic, Peter Rosset of Food First said, “Complex problems of hunger and agricultural development will not be solved by technological silver bullets.” I couldn’t agree more!

And even if it could be done, biotechnology would not be that bullet. Our world and its increases in population and food shortages are too complex to be addressed adequately with simple solutions—whether they are the application of biotechnology or the use of organic methods to address agricultural problems. The question for me really is, can biotechnology ease problems of food insufficiency and environmental degradation, due in large part to population expansion?

First, as a practicing scientist in the field of biotechnology and genomics, I remind you that agricultural biotechnology is more than just genetically modified organisms. Based on what we have learned about manipulating plant tissues and DNA, alternative approaches have been developed that don’t involve genetic engineering, and some of these are important in developing countries.

A recent example is a new pearl millet hybrid to be released in India that is resistant to downy mildew. In years of severe attack, this organism can cause the loss of up to 30% of the crop.

Another example involves micropropagation methods to rid plants, like banana, potatoes and taro, of viruses and other pests by passing them through tissue culture. This has helped African and Philippino farmers. Although tissue-cultured plants cost more, disease-free plants give higher yields, resulting in more money for farmers.

The last example is Polymerase Chain Reaction (PCR) techniques, which are being used to detect and control pests and viruses in crops like banana and papaya.

But when biotechnology is discussed, most of the focus is on genetic engineering of crop plants —adding new or modified genes. Here I want to focus on the question of whether this technology holds any hope for developing countries.

I would first like to look at the impact of genetically engineered crops available commercially today. An example is transgenic Bt* plants like corn, potatoes, and cotton. The agricultural economist David Zilberman and his colleagues at UC Berkeley concluded that increases in yields of Bt cotton could be be significant in countries where there are a lot of pests, but minimal pesticide use—like some developing countries. They calculated that, although Bt cotton gains in the U.S. and China would range from 0-15%, gains in South Africa could be 20-40%, and in India 60-80%.

But won’t intellectual property issues interfere with deployment of such crops in developing countries, since U.S. companies created them? Zilberman and other agricultural economists claim that, since these crops are generated in developed countries, the companies generally do not patent these inventions in developing countries. They worry most about liability and transaction costs.

Use of genetically engineered crops in Africa, for example, has faced controversy. Some claim that the presently available crops, like Bt corn, do not address small farmers’ needs in developing countries and that they will be expensive—only agrochemical companies developing them will benefit. Also, these crops will make farmers dependent on the new varieties, and the biodiversity of the old varieties will be lost. In addition, genetically engineered crops might pose environmental risks by leading to insect resistance, gene flow into wild species, and disruption of non-target organisms.

Most farmers in Kenya use local varieties, and they select varieties based on yield, early maturity and tolerance to drought, field pests and storage pests. One approach is to involve these farmers in testing the new varieties of maize. Working within the Kenyan regulatory system, existing Bt technology has been found to be effective in the laboratory on leaf samples against all major stem borer species, except one.

The next step is to test the Bt varieties in biosafety greenhouses and in open quarantine facilities. Finally, local farmers will test these crops in the field.

No patents were filed in Kenya restricting the use of Bt genes in maize. Therefore, Bt maize is likely to be commercialized by local Kenyan companies. Since Bt genes are dominant, farmers don’t need to become dependent on the seed industry since they can recycle seed. In addition, farmers are free to incorporate the gene into local varieties, if they view it as a valuable trait.

Is this a “magic bullet” solution? No, it is only one approach. Biotechnology must be pursued as part of a portfolio of technologies used to enhance productivity and environmental sustainability of agriculture. Although agricultural technology, like any other technology, will never be “zero risk.” If it is carefully considered and introduced, shouldn’t farmers and consumers be able to try these products and help develop varieties suited to their local areas? 

Is this the only way to address these problems? Certainly not. In many cases the problem is not as simple as pest resistance in maize. Are the food and agricultural problems of poor countries like those of rich countries? No, for the poor in most developing countries, things are different—they live in different ecological zones, face different health conditions, and must overcome agronomic limitations very different from those of developed countries.

I believe that science, technology, economics and government policy must all be directed toward solving these problems. Technological gains in developed countries will only be minimally applicable to problems in poorer countries. Technologies directed to poorer countries are not likely to reap economic rewards. Therefore, the private sector is not likely to assume a major responsibility in this area.

This brings me to the last point. What about the role of public sector scientists, both in developed countries and in the developing countries? Finally we come to a topic where I have some personal experience. For years, my laboratory has worked on the genetic engineering of cereal crops. One application focused on reducing wheat allergenicity—a problem of little significance in developing countries. But another application of the same technology appears to improve protein and starch digestibility—a recognized problem with sorghum, a staple in parts of Africa.

For this reason colleague Bob Buchanan and I are attempting to improve the nutritional quality of sorghum. We are focusing on improving its digestibility and its amino acid profile, given that cereals are notoriously deficient in lysine.

We found a U.S. company with a modified barley gene that could improve lysine content, and we approached them for the project. We have worked out the intellectual property issues, and are currently introducing this gene into sorghum. Of course, before this is released to African farmers, liability and environmental and food safety issues have to be addressed, The project is moving forward.

There are potential problems in introducing these crops into developing countries, just as there are dangers in introducing other elements of our agricultural system. Care needs to be taken in releasing genetically engineered varieties in areas where there are wild relatives of the commercially grown crop. But this warning is tempered by the fact that you have to look at the actual genes that will be introduced to see if this might cause problems if they were to escape. In our sorghum project, we are working with a sorghum breeder in the Midwest to assess the possible consequences of the movement of our genes into wild species.

Genes have been flowing back and forth between sorghum and their wild relatives for millennia. The issue becomes what effect—negative or positive—might the particular genes we are using have? If our approaches are successful and we can address food and environmental safety issues, African breeders will move these genes into local sorghum varieties.

Why did we become involved in this project? For me personally, I believe it is part of my mandate as a public sector scientist to use the skills I have to make a contribution to improve the lot of farmers and consumers in developing countries. Is this the only answer? Is this the best answer? No, it is only part of an answer, but it is something I want to and can do.

It has been said that one-fifth of the world’s population is at the bottom of the economic ladder, and over 95% of their food supply is produced locally. Therefore, improving agricultural productivity in developing countries may more directly benefit “consumers,” since in many cases they are also “producers.” Increasing local food production will also contribute to lower food costs and food security. I hope that I can use my knowledge of science and cooperative extension to make a difference in the developing world.

^{*Bacillus thuringiensis, commonly known as Bt, is a bacterium that occurs naturally in soil. Some strains of Bt produce proteins that kill certain insects, but are not harmful to humans, other mammals, birds, or fish. Certain crop plants have been genetically engineered to produce their own Bt.}

^{Dr. Lemaux is a faculty member and Cooperative Extension Specialist, Dept. of Plant and Microbial Biology at the Univ. of Calif. Berkeley plantandmicrobiology.berkeley.edu Her work on sorghum is funded by the Bill & Melinda Gates Foundation. She’s also a popular speaker on agriculture and biotechnology ucbiotech.org This lecture is an excerpt from the Future of Food Symposium: Value vs. Risk in the Biotechnology Debate at Santa Clara University (4/15/05).}