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INTRODUCTION |
During the 20th century,
conventional breeding produced a vast number of varieties and hybrids
that contributed immensely to higher grain yield, stability of
harvests, and farm income. Despite the successes of the Green
Revolution, the battle to ensure food security for hundreds of
millions miserably poor people is far from won. Mushrooming
populations, changing demographics, and inadequate poverty intervention
programs have eroded many of the gains of the Green Revolution. This is
not to say that the Green Revolution is over. Increases in crop
management productivity can be made all along the line: in tillage,
water use, fertilization, weed and pest control, and harvesting.
However, for the genetic improvement of food crops to continue at a
pace sufficient to meet the needs of the 8.3 billion people projected
to be on this planet at the end of the quarter century, both
conventional technology and biotechnology are needed.
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WHAT CAN WE EXPECT FROM BIOTECHNOLOGY? |
The majority of agricultural scientists, including myself,
anticipate great benefits from biotechnology in the coming decades to
help meet our future needs for food and fiber. The commercial adoption
by farmers of transgenic crops has been one of the most rapid cases of
technology diffusion in the history of agriculture. Between 1996 and
1999, the area planted commercially with transgenic crops has increased
from 1.7 to 39.9 million ha (James, 1999
). In the last 20 years,
biotechnology has developed invaluable new scientific methodologies and
products, which need active financial and organizational support to
bring them to fruition. So far, biotechnology has had the greatest
impact in medicine and public health. However, there are a number of
fascinating developments that are approaching commercial applications
in agriculture.
Transgenic varieties and hybrids of cotton, maize, and potatoes,
containing genes from Bacillus thuringiensis that
effectively control a number of serious insect pests, are now being
successfully introduced commercially in the United States. The use of
such varieties will greatly reduce the need for insecticides.
Considerable progress also has been made in the development of
transgenic plants of cotton, maize, oilseed rape, soybeans, sugar beet,
and wheat, with tolerance to a number of herbicides. The development of
these plants could lead to a reduction in overall herbicide use through more specific interventions and dosages. Not only will this development lower production costs; it also has important environmental advantages.
Good progress has been made in developing cereal varieties with greater
tolerance for soil alkalinity, free aluminum, and iron toxicities.
These varieties will help to ameliorate the soil degradation problems
that have developed in many existing irrigation systems. These
varieties will also allow agriculture to succeed in acidic soil areas,
thus adding more arable land to the global production base. Greater
tolerance of abiotic extremes, such as drought, heat, and cold, will
benefit irrigated areas in several ways. We will be able to achieve
more crop per drop by designing plants with reduced water requirements
and adopting between-crop/water management systems. Recombinant DNA
techniques can speed up the development process.
There are also hopeful signs that we will be able to improve
fertilizer-use efficiency by genetically engineering wheat and other
crops to have high levels of Glu dehydrogenase. Transgenic wheats with
high Glu dehydrogenase, for example, yielded up to 29% more
crop with the same amount of fertilizer than did the normal crop
(Smil, 1999).
Transgenic plants that can control viral and fungal diseases are
not nearly as developed. Nevertheless, there are some promising examples of specific virus coat genes in transgenic varieties of
potatoes and rice that confer considerable protection. Other promising genes for disease resistance are being incorporated into other crop species through transgenic manipulations.
I would like to share one dream that I hope scientists will achieve in
the not-too-distant future. Rice is the only cereal that has immunity
to the Puccinia sp. of rust. Imagine the benefits if the
genes for rust immunity in rice could be transferred into wheat,
barley, oats, maize, millet, and sorghum. The world could finally be
free of the scourge of the rusts, which have led to so many famines
over human history.
The power of genetic engineering to improve the nutritional quality of
our food crop species is also immense. Scientists have long had an
interest in improving maize protein quality. More than 70 years ago,
researchers determined the importance of certain amino acids for
nutrition. More than 50 years ago, scientists began a search for a
maize kernel that had higher levels of Lys and Trp, two essential amino
acids that are normally deficient in maize. Thirty-six years ago,
scientists at Purdue University (West Lafayette, IN) discovered a
floury maize grain from the South American Andean highlands carrying
the opaque-2 gene that had much higher levels of Lys and Trp. But as is
all too often the case in plant breeding, a highly desirable trait
turned out to be closely associated with several undesirable ones. The
dull, chalky, soft opaque-2 maize kernels yielded 15% to
20% less grain weight than normal maize grain. However, scientists
from the International Maize and Wheat Improvement Center (Mexico City)
who were working with opaque-2 maize observed little
islands of translucent starch in some opaque-2 endosperms. Using
conventional breeding methodologies supported by rapid chemical
analysis of large numbers of samples, the scientists were able to
slowly accumulate modifier genes to convert the original soft
opaque-2 endosperm into vitreous, hard endosperm types.
This conversion took nearly 20 years. Had genetic engineering
techniques been available then, the genes that controlled high Lys and
Trp could have been inserted into high-yielding hard-endosperm phenotypes. Thus through the use of genetic engineering tools, instead
of a 35-year gestation period, quality protein maize could have been
available to improve human and animal nutrition 20 years earlier. This
is the power of the new science.
Scientists from the Swiss Federal Institute of Technology (Zurich) and
the International Rice Research Institute (Los Baños, The
Philippines) have recently succeeded in transferring genes into rice to
increase the quantities of vitamin A, iron, and other micronutrients.
This work could eventually have profound impact for millions of people
with deficiencies of vitamin A and iron, causes of blindness and
anemia, respectively.
Because most of the genetic engineering research is being done by
the private sector, which patents its inventions, agricultural policy
makers must face a potentially serious problem. How will these
resource-poor farmers of the world be able to gain access to the
products of biotechnology research? How long, and under what terms,
should patents be granted for bioengineered products? Furthermore, the
high cost of biotechnology research is leading to a rapid consolidation
in the ownership of agricultural life science companies. Is this
consolidation desirable? These issues are matters for serious
consideration by national, regional, and global governmental organizations.
National governments need to be prepared to work with and benefit from
the new breakthroughs in biotechnology. First and foremost, governments
must establish regulatory frameworks to guide the testing and use of
genetically modified crops. These rules and regulations should be
reasonable in terms of risk aversion and implementation costs. Science
must not be hobbled by excessively restrictive regulations. Since much
of the biotechnology research is under way in the private sector, the
issue of intellectual property rights must be addressed and accorded
adequate safeguards by national governments.
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STANDING UP TO THE ANTISCIENCE CROWD |
The world has or will soon have the agricultural technology
available to feed the 8.3 billion people anticipated in the next quarter of a century. The more pertinent question today is whether farmers and ranchers will be permitted to use that technology. Extremists in the environmental movement, largely from rich nations and/or the privileged strata of society in poor nations, seem to be
doing everything they can to stop scientific progress in its tracks. It
is sad that some scientists, many of whom should or do know better,
have also jumped on the extremist environmental bandwagon in search of
research funds. When scientists align themselves with antiscience
political movements or lend their name to unscientific propositions,
what are we to think? Is it any wonder that science is losing its
constituency? We must be on guard against politically opportunistic,
pseudo-scientists like the late Trofim D. Lysenko, whose bizarre
ideas and vicious persecution of his detractors contributed greatly to
the collapse of the former USSR.
We all owe a debt of gratitude to the environmental movement that has
taken place over the past 40 years. This movement has led to
legislation to improve air and water quality, protect wildlife, control
the disposal of toxic wastes, protect the soils, and reduce the loss of
biodiversity. It is ironic, therefore, that the platform of the
antibiotechnology extremists, if it were to be adopted, would have
grievous consequences for both the environment and humanity. I often
ask the critics of modern agricultural technology: What would the world
have been like without the technological advances that have occurred?
For those who profess a concern for protecting the environment,
consider the positive impact resulting from the application of
science-based technology. Had 1961 average world cereal yields (1,531 kg/ha) still prevailed, nearly 850 million ha of additional land of the
same quality would have been needed to equal the 1999 cereal harvest
(2.06 billion gross metric tons). It is obvious that such a surplus of
land was not available, and certainly not in populous Asia. Moreover,
even if it were available, think of the soil erosion and the loss of
forests, grasslands, and wildlife that would have resulted had we tried to produce these larger harvests with the older, low-input technology! Nevertheless, the antibiotechnology zealots continue to wage their campaigns of propaganda and vandalism.
One particularly egregious example of antibiotechnology propaganda came
to my attention during a recent field tour to Africa. An article in The
Independent (Walsh, 2000) newspaper from London, entitled
"America Finds Ready Market for Genetically Modified Food: the
Hungry," is accompanied by a ghastly photograph depicting a man near
death from starvation, lying next to food sacks. The caption below
reads "Sudanese man collapsing as he waits for food from the UN World
Food Program."
The article's author, Declan Walsh, writing from Nairobi, implies that
there is a conspiracy between the U.S. government and the World Food
Program (WFP) to dump unsafe, American, genetically modified
crops into the one remaining unquestioning market: emergency aid for
the world's starving and displaced. I, for one, take heartfelt umbrage
against this insult to the WFP, whose workers and collaborators helped
feed 86 million people in 82 countries in 1999. The employees of the
WFP are among the world's unsung heroes, who struggle against the
clock and under exceedingly difficult conditions to save people from
famine. Their achievements, dedication, and bravery deserve our highest
respect and praise.
In his article, Walsh quotes several critics of the use of genetically
modified food in Africa. Elfrieda Pschorn-Strauss, from the South
African organization Biowatch, says "The US does not need to
grow nor donate genetically modified crops. To donate untested food and
seed to Africa is not an act of kindness but an attempt to lure Africa
into further dependence on foreign aid." Dr. Tewolde Gebre
Egziabher of Ethiopia states that "Countries in the grip of a
crisis are unlikely to have leverage to say, `This crop is
contaminated; we're not taking it.' They should not be faced with a
dilemma between allowing a million people to starve to death and
allowing their genetic pool to be polluted." Neither of these
individuals offers any credible scientific evidence to back their false
assertions concerning the safety of genetically modified foods. The WFP
only accepts food donations that fully meet the safety standards in the
donor country. In the United States, genetically modified foods are
judged to be safe by the Department of Agriculture, the Food and Drug
Administration, and the Environmental Protection Agency and thus they
are acceptable to the WFP. That the European Union has placed a
2-year moratorium on genetically modified imports says little per se
about food safety, but rather it says more about consumer
concerns, largely the result of unsubstantiated scare mongering
done by opponents of genetic engineering.
Let's consider the underlying thrust of Walsh's article that
genetically modified food is unnatural and unsafe. Genetically modified
organisms and genetically modified foods are imprecise terms that refer
to the use of transgenic crops (i.e. those grown from seeds that
contain the genes of different species). The fact is that genetic
modification started long before humankind started altering crops by
artificial selection. Mother Nature did it, and often in a big way. For
example, the wheat groups we rely on for much of our food supply are
the result of unusual (but natural) crosses between different species
of grasses. Today's bread wheat is the result of the hybridization of
three different plant genomes, each containing a set of seven
chromosomes, and thus could easily be classified as transgenic. Maize
is another crop that is the product of transgenic hybridization
(probably of teosinte and Tripsacum). Neolithic humans
domesticated virtually all of our food and livestock species over a
relatively short period 10,000 to 15,000 years ago. Several hundred
generations of farmer descendents were subsequently responsible for
making enormous genetic modifications in all of our major crop and
animal species. To see how far the evolutionary changes have come, one only needs to look at the 5,000-year-old fossilized corn cobs found in
the caves of Tehuacan in Mexico, which are about one-tenth the size of
modern maize varieties. Thanks to the development of science over the
past 150 years, we now have the insights into plant genetics and
breeding to do purposefully what Mother Nature did herself in the past
by chance.
Genetic modification of crops is not some kind of witchcraft; rather,
it is the progressive harnessing of the forces of nature to the benefit
of feeding the human race. The genetic engineering of plants at the
molecular level is just another step in humankind's deepening
scientific journey into living genomes. Genetic engineering is not a
replacement of conventional breeding but rather a complementary research tool to identify desirable genes from remotely related taxonomic groups and transfer these genes more quickly and precisely into high-yield, high-quality crop varieties. To date, there has been
no credible scientific evidence to suggest that the ingestion of
transgenic products is injurious to human health or the environment. Scientists have debated the possible benefits of transgenic products versus the risks society is willing to take. Certainly, zero risk is
unrealistic and probably unattainable. Scientific advances always
involve some risk that unintended outcomes could occur. So far, the
most prestigious national academies of science, and now even the
Vatican, have come out in support of genetic engineering to improve the
quantity, quality, and availability of food supplies. The more
important matters of concern by civil societies should be equity issues
related to genetic ownership, control, and access to transgenic
agricultural products.
One of the great challenges facing society in the 21st century will be
a renewal and broadening of scientific education at all age levels that
keeps pace with the times. Nowhere is it more important for knowledge
to confront fear born of ignorance than in the production of food,
still the basic human activity. In particular, we need to close the
biological science knowledge gap in the affluent societies now
thoroughly urban and removed from any tangible relationship to the
land. The needless confrontation of consumers against the use of
transgenic crop technology in Europe and elsewhere might have been
avoided had more people received a better education about genetic
diversity and variation. Privileged societies have the luxury of
adopting a very low-risk position on the genetically modified crop
issue, even if this action later turns out to be unnecessary. But the
vast majority of humankind, including the hungry victims of wars,
natural disasters, and economic crises who are served by the WFP, does
not have such a luxury. I agree with Mr. Walsh when he speculates that
esoteric arguments about the genetic make-up of a bag of grain mean
little to those for whom food aid is a matter of life or death. He
should take this thought more deeply to heart.
We cannot turn back the clock on agriculture and only use methods that
were developed to feed a much smaller population. It took some 10,000 years to expand food production to the current level of about 5 billion
tons per year. By 2025, we will have to nearly double current
production again. This increase cannot be accomplished unless farmers
across the world have access to current high-yielding crop production
methods as well as new biotechnological breakthroughs that can increase
the yields, dependability, and nutritional quality of our basic food
crops. We need to bring common sense into the debate on agricultural
science and technology and the sooner the better!
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CONCLUSIONS |
Thirty years ago, in my acceptance speech for the Nobel Peace
Prize, I said that the Green Revolution had won a temporary success in
man's war against hunger, which if fully implemented, could provide
sufficient food for humankind through the end of the 20th century. But
I warned that unless the frightening power of human reproduction
was curbed, the success of the Green Revolution would only be ephemeral.
I now say that the world has the technology that is either available or
well advanced in the research pipeline to feed a population of 10 billion people. The more pertinent question today is: Will farmers and ranchers will be permitted to use this new technology?
Extreme environmental elitists seem to be doing everything they can to
derail scientific progress. Small, well-financed, vociferous, and
antiscience groups are threatening the development and application of
new technology, whether it is developed from biotechnology or more
conventional methods of agricultural science.
I agree fully with a petition written by Professor C.S. Prakash
of Tuskegee University, and now signed by several thousand scientists worldwide, in support of agricultural biotechnology, which
states that no food products, whether produced with recombinant DNA
techniques or more traditional methods, are totally without risk. The
risks posed by foods are a function of the biological characteristics
of those foods and the specific genes that have been used, not of the
processes employed in their development.
The affluent nations can afford to adopt elitist positions and pay more
for food produced by the so-called natural methods; the 1 billion
chronically poor and hungry people of this world cannot. New technology
will be their salvation, freeing them from obsolete, low-yielding, and
more costly production technology.
Most certainly, agricultural scientists and leaders have a moral
obligation to warn the political, educational, and religious leaders
about the magnitude and seriousness of the arable land, food, and
population problems that lie ahead, even with breakthroughs in
biotechnology. If we fail to do so, then we will be negligent in our
duty and inadvertently may be contributing to the pending chaos of
incalculable millions of deaths by starvation. But we must also speak
unequivocally and convincingly to policy makers that global food
insecurity will not disappear without new technology; to ignore this
reality will make future solutions all the more difficult to achieve.
TOP
INTRODUCTION
WHAT CAN WE EXPECT...
