Today in AgBioView from www.agbioworld.org: September 17, 2006
* Spinach Company Faces Unwelcome Scrutiny
* FDA Links Spinach E. Coli Risk to Calif. Company
* EU: Biotech rice illegal but likely safe
* A seedbed of revolution
* A Growth Industry
* The victory of GM technology
* Define 'Precautionary Principle' to avoid clashes over biotechnology
* New study shows nutrition has greater impact than biotech content on soil organisms
* The breeder's dilemma - yield or nutrition?
* World Health Org. clears DDT spraying for malaria
Spinach Company Faces Unwelcome Scrutiny
- Associated Press, By JORDAN ROBERTSON, Sep 16, 2006
SAN JUAN BAUTISTA, Calif. -- Earthbound Farm, the country's largest grower of organic produce, is facing unwelcome scrutiny after federal officials linked a nationwide E. coli outbreak to its bagged spinach.
The company, also known by its legal name Natural Selection Foods LLC, recalled and stopped shipping all its spinach products after E. coli outbreaks killed one person and sickened more than 100 others in 19 states.
Earthbound officials were working with state and federal health inspectors to pinpoint the source of the contamination, spokeswoman Samantha Cabaluna said Saturday.
"We're not even thinking about the cost right now," Cabaluna said. "We're trying to do the right thing, to protect public health and get to the bottom of this."
The U.S. Food and Drug Administration has warned consumers not to eat fresh spinach, and grocery stores nationwide have pulled nearly all spinach products from their shelves. As the investigation continues, other brands may be implicated, officials said.
All of Earthbound's spinach is grown in fields around the Salinas Valley, then washed and packaged at its plant in San Juan Bautista, about 90 miles south of San Francisco, Cabaluna said.
Privately held Earthbound is under contract with other food companies to produce and package spinach under about 30 different brand labels sold in supermarkets across North America.
The company packages both organic and conventionally grown spinach in separate areas at its San Juan Bautista plant, but it was still unclear which type of spinach made people ill, Cabaluna said.
Customers who bought bagged spinach produced by Earthbound should return the product to the grocery store where they bought it or contact the company for a refund, Cabaluna said.
"We're very, very upset about this because we're in the business of providing healthy foods," Cabaluna said.
Earthbound was started as a 2 1/2 acre farm by New York natives Myra and Drew Goodman in 1984.
The company began selling bags of pre-washed salads in 1986. Since then, the market for ready-to-eat bagged greens has grown to nearly $3 billion.
With about 1,100 employees, Earthbound now sells more than 100 types of fruits and vegetables grown on 29,000 acres in California, Arizona, Mexico and other locations in the U.S. and abroad.
Earthbound sells more than 70 percent of the country's bagged organic salad and processes about 30 million salad servings each week, according to the company. Its produce can be found in nearly three-quarters of U.S. supermarkets and in all 50 states and Canada.
Cabaluna did not know how much bagged spinach the company grows and processes each year.
About 74 percent of the fresh market spinach grown in the U.S. comes from California, according to the California Farm Bureau Federation.
The situation indicates a larger problem within the farming and distribution process, federation spokesman Dave Kranz said.
"First, we need to make sure everything is as tight as can be on everyone's individual operations," Kranz said, "and then we see if other changes to the process need to be made."
FDA Links Spinach E. Coli Risk to Calif. Company
- NPR's All Things Considered, September 15, 2006, by John McChesney
The FDA says it has linked the E. coli outbreak from bagged, pre-washed spinach to only one place so far: a large, organic foods supplier in California.
Late Friday, Earthbound Farms of California decided to voluntarily pull all of the company's spinach from store shelves. Its Natural Selection Foods brand was linked to the outbreak. Its products are sold under various names, including Selection Foods, Rave Spinach, Dole, Earthbound Farm, Trader Joe's and Ready Pac.
The tainted spinach has made nearly 100 people sick in 20 states. It is being blamed for at least one death.
But federal officials warn that the tainted spinach may be found in products other than those from Natural Selection, which is based in San Juan Bautista, Calif.
Robert Brackett is the director of the Federal Food and Drug Administration's Center for Food Safety. He says if you have packaged spinach that you purchased recently, you should dump it.
"Once the organism is on the tissue itself, it is extremely difficult to eliminate. Even when the consumer washes it in their own home, they're not going to get rid of the E. coli if it's there," Brackett says.
The FDA has issued a warning to all states, because it's unknown at this time how widely the product has been distributed.
So far the tainted spinach has turned up in nine states: Connecticut, Idaho, Indiana, Michigan, New Mexico, Oregon Utah, Kentucky and Wisconsin, where 20 people got sick and one died.
"E. coli grow in the intestines of cattle," says Carol Tucker Foreman of the Consumer Federation of America. "The fact that spinach has been infected with this organism means that the spinach somehow came into contact with cattle feces. That might happen in an open field if they were using unsterilized manure," Foreman says.
In 1993, four children died in an outbreak traced to Jack in the Box hamburgers. That led to major reforms in the way ground beef is inspected. But Foreman says similar inspections of packaged produce are not in place.
"They are not inspected on a regular basis; there is no regular testing to make sure that whatever efforts a company is making are effective," she says.
During this time of year the Salinas Valley in California is the nation's major source of fresh spinach. Much of it is grown organically, often fertilized with cow manure. Advocates of organic farming are worried that their industry may be tarnished by the outbreak.
The FDA's Robert Brackett says his agency is focusing on more than the organic produce industry:
"Well, we're looking at all of them. Anybody that would be using a raw animal manure, of course, would automatically rise to the top of our list to look at."
Brackett says the task ahead is to identify specific brands, and even specific case lots, that may be the source of the problem.
EU: Biotech rice illegal but likely safe
- AP, Sep 15, 2006
BRUSSELS, Belgium - Genetically modified rice illegally imported into Europe is unlikely to pose any safety concerns to humans or animals, but must still be recalled, the European Commission said Friday.
Philip Tod, consumer protection spokesman for the European Union , said a European food safety agency had conducted tests on the rice.
Liberty Link Rice 601 was developed by Aventis CropScience, which was taken over by Germany‘s Bayer AG in 2002 and renamed Bayer Crop Science. Bayer announced in July it had found the 601 strain in storage units in Arkansas and Missouri. Since then, the EU has tightened screening to stop the product from entering its market.
EU regulators are in contact with Greenpeace, Tod said.
A seedbed of revolution
Africa needs markets, as well as technology, for a green revolution to take root
- THE ECONOMIST, Sep 14th 2006
Norman Borlaug, who won the Nobel peace prize in 1970 for his role in the green revolution, remains as sturdy and "high-yielding" as the varieties of wheat he helped to invent. Last week, at the age of 92, he gave a stirring lecture in Washington, DC, calling for a renewed effort to bring his revolution to Africa, the one continent it bypassed first time around.
As if in answer to his plea, the Rockefeller Foundation, Mr Borlaug's former employer, and the Gates Foundation-run by Bill Gates, founder of Microsoft, and his wife Melinda-said this week they would devote $150m over five years to the cause. Some of this money ($63m) will be spent training more crop scientists and breeding new seed varieties suited to sub-Saharan Africa's parched climate, denuded soils and stubborn pests. But the two foundations, appreciating that technology is not the only obstacle, will spend almost as much ($61m) on the distribution of seeds as on their discovery. They will, for example, help village retailers and seed wholesalers set up in business, and push for financial reforms that would enable farmers and their suppliers to get credit.
The money is welcome, because crop science of the sort Mr Borlaug made famous has fallen out of fashion in recent decades. The International Rice Research Institute, for example, lost a quarter of its core funding between 2001 and 2003. These days biotechnology is mainly a profit-driven enterprise, creating seeds for big farms, often in rich countries. This skews its research, says Michael Lipton, of the University of Sussex. Herbicide-resistant crops, for example, allow weeds to be killed chemically, rather than plucked manually. This might reduce the demand for farm labour, which is scarce in rich countries, but in need of employment in poor ones.
But the sums announced this week, spread across as many as 20 countries, are not much in the scheme of things. The World Bank, for example, lent $537m to Africa for rural development in fiscal 2005 alone, without exciting much media interest. More importantly, the member governments of the African Union promised in Maputo in 2003 to devote at least a tenth of their budgets to agriculture by 2008, a scale of resources orders of magnitude greater than the Gates and Rockefeller millions.
This matters, because the green revolution's triumph in Asia owed as much to political commitment as it did to technical ingenuity. As Peter Timmer, a fellow at the Centre for Global Development, points out, Asian nations were too big to rely on food imports and too proud to depend indefinitely on the food aid America offered in return for loyalty in the cold war. New technologies were a necessary condition for the green revolution, but not a sufficient one. It succeeded because Asian governments made sure their farmers, big and small, were able and willing to avail themselves of fertiliser, irrigation and connections to markets. If Mr Borlaug was the father of the revolution, political necessity was its mother.
Why did Africa fail to emulate this success? Neither nature nor technology is the answer, according to a recent book on the subject*. Seed varieties suited to Africa's difficult conditions-where crops are watered by intermittent rains, not by a reliable system of irrigation-were invented. The first synthetic maize was released in Kenya in 1961 and even lowly cassava, a starchy root vegetable, benefited from genetic embellishments in the 1970s. But with some exceptions Africa's governments saw the new seeds and fertiliser as a way to secure political favour, not the food supply. In Nigeria credit and subsidies were hogged by "absentee farmers, retired civil servants and soldiers". Ethiopia's poor roads left the country's markets so fragmented that in 2001 smallholders in one part of the country were almost ruined by a glut, even as farmers elsewhere were ruined by drought.
Farmers in sub-Saharan Africa now use only about 9kg of fertiliser per hectare on average, compared with 142kg in South-East Asia. Their reluctance has been put down to ignorance (farmers do not appreciate the benefits of fertiliser until they have tried it), timidity (they are wary of upfront commitments of money and prefer farming that delivers a reliable, even if low, return) or illiquidity (farmers cannot get the credit they need to afford seeds and fertiliser).
Food, glorious food
Few countries have ever enjoyed an industrial revolution without first undergoing a revolution in agriculture, a point both Mr Gates and Mr Timmer are keen to stress. Besides, raising yields on smallholder farms would have happy distributional consequences. Food is doubly important to the poor, because growing it accounts for a big share of their employment and buying it accounts for a big share of their expenditure. Raising farm productivity should, in principle, raise the incomes the rural poor earn from the food they sell, even as it reduces the price the urban poor must pay for the food they buy.
But cultivating a resilient, bountiful crop may be easier than cultivating an equally thriving market, with access to credit and distribution channels. The foundations understand this task, but no charity, however large, can accomplish it. African governments say they also understand it and have been as good as their word, recently agreeing to drop tariffs on the cross-border sale of fertiliser, a particular boon to landlocked countries.
For his part, Mr Borlaug is undeterred. For a nonagenarian, he puts great faith in youthful optimism. He wants to recruit "young people, right out of school" to his banner, reaching them before they have become accustomed to failure. In this business, the revolutionaries, as well as their seeds, must be resistant to the common blight of defeatism and despair.
A Growth Industry
- Philadelphia Inquirer, By Harold Brubaker, Sep. 17, 2006
American farmers have adopted genetically modified crops with a vengeance since their introduction 10 years ago.
Biotech seeds - available since 1996 - already account for 61 percent of the corn, 83 percent of the cotton, and 89 percent of the soybeans planted in the United States.
"From a farmer's perspective, it was basically a pretty wonderful invention," said Abram Bakker, who farms 600 acres in Cumberland County, N.J., and uses herbicide-tolerant soybeans in crop rotations. "It's made it a lot simpler, more cost-effective, and you're putting less chemicals into the environment," he said.
Plants genetically engineered to resist insects and withstand herbicides dominate the market now, but DuPont Co.'s Pioneer subsidiary and other biotechnology companies have bigger plans: for plants that tolerate drought, soybeans that contain healthier oils, and plants that produce drugs and industrial chemicals more efficiently than factories.
In a laboratory called "The Bean Scene" at DuPont's Experimental Station in Wilmington, for example, researchers have engineered soybeans to produce high levels of oleic acid and are working on beans with enhanced omega-3 oil content. Both are considered healthy fats.
Yet, despite its momentum, agricultural biotechnology keeps stumbling in ways that raise doubts about how carefully government regulators and industry are handling the relatively new technology.
Consider last month's report from Bayer Cropscience that it had found traces of an unapproved genetically modified rice - which Bayer had stopped field-testing in 2001 - in American long-grain rice.
Such incidents "contribute to what is ultimately slowing down the industry, and that is a public concern about biotechnology that is translated into market restrictions," said Gregory Conko, a senior fellow at Competitive Enterprise Institute in Washington.
The United States Department of Agriculture said the rice - which contains a protein that allows it to tolerate a herbicide - poses no danger to humans and has put it on a fast track for approval.
"This isn't the tomato that ate Cleveland," said Norman C. Ellstrand, a professor of genetics at the University of California, Riverside.
"What matters to me largely is that it sets a bad precedent. There will be transgenic crops coming down the pike that we will want to have contained," said Ellstrand, who studies the movement of genes from cultivated to wild plants.
Cindy Smith, the USDA's deputy administrator for Biotechnology Regulatory Services, said the unit was modifying its regulations to keep pace with the "very complex, very rapidly evolving technology."
She said the agency's "focus is to ensure that the technology moves forward, but does so in a safe manner."
Critics of agricultural biotechnology worry about the USDA's dual role as promoter and regulator of biotechnology. "It's not a good combination," said Jane Rissler, a senior scientist with the Union of Concerned Scientists in Washington.
The public reaction to last month's rice incident has been muted, especially compared with the discovery six years ago that genetically engineered corn approved only for animal consumption slipped into the human food supply.
The concern in 2000 was that the corn could cause an allergic reaction in some people. In the rice case, the protein in question has been approved for human consumption in 12 other countries.
The rice discovery turned into a headache for U.S. rice exporters, who now have to certify their crop as nontransgenic before it can be shipped to the European Union and Japan. But other parts of the food industry remained unfazed.
"This is not a food-safety issue, but rather a question of regulatory permissibility in certain markets outside of North America," Kris Charles, a Kellogg Co. representative, said.
"Here in the U.S., most consumers are not concerned about biotechnology, and we receive very few contacts on the subject from either the public or our retail customers," Charles said.
Indeed, genetically modified crops are not a top-of-the-mind issue for most Americans, according to the Pew Initiative on Food and Biotechnology at the University of Richmond. Still, opponents of the technology have persisted in trying to block its spread.
"Until USDA gets its act together," in its efforts to keep genetically modified plants from mixing with natural plants, "we recommend a moratorium on all new permits for open-air field-testing of genetically engineered crops not permitted in the food supply," said Bill Freese, a science policy analyst at the Center for Food Safety in Washington.
Michael Fernandez, executive director the Pew biotech center, said it was not realistic to "expect 100 percent purity in any biological system growing out in the open... . In traditional agriculture there is no expectation that there will 100 percent purity in seed."
Some scientists said they were not worried by the escape of genes that provided herbicide tolerance and insect resistance but were troubled by the potential entry of genes that caused plants to produce drugs or chemicals into food plants.
Smith, head of Biotechnology Regulatory Services, said the government had instituted stricter regulations on the field-testing of such crops. Under the old regimen, each test field was inspected once. Now each is inspected seven times: five times during the growing season and twice in the year after, Smith said.
This year, 181 acres in eight states were planted with crops that produce pharmaceuticals or industrial chemicals, according to Rachel Iadicicco, a spokeswoman for the USDA's Animal and Plant Health Inspection Service.
While the U.S. food industry is generally supportive of agricultural biotechnology, it is wary of "biopharming." For example, Anheuser-Busch Cos. Inc. threatened last year to stop buying rice from Missouri if a California biotech company planted rice there enhanced with synthetic human genes.
Such concerns have slowed down the expansion of this area of biotechnology.
"I think people both within the industry... and neutral observers of the industry thought we would be in an entirely different place 10 years on," said Conko, the Competitive Enterprise Institute fellow.
Some of the science has turned out to be more difficult than initially expected, and market acceptance - especially overseas - has not been achieved for some crops.
For example, government regulators have cleared genetically engineered rice, potatoes and wheat, but they are not commercially available now because the industry made a decision that the market was not ready for them, said Michael Phillips, vice president of food and agriculture at the Biotechnology Industry Organization in Washington.
Genetically modified crops have been adopted at a phenomenal pace, but "if those areas had been opened up, it could be much bigger."
Letter: The victory of GM technology
- THE INDEPENDENT, By Jack Pridham, 15 September 2006
Sir: I would interpret the fact that GM crops are not being grown in England somewhat differently from the councillors from Norwich (Letters, 8 September) who believe it to be "a real victory" achieved by "the green movement and all sensible people who believe in the precautionary principle".
It is highly probable that history will show that most "sensible people" may reside in the more than 20 countries across the world (including at least three in Europe) which are cultivating GM crops on a billion acres of land. Furthermore, the "victory", if it occurs, will probably be classified as pyrrhic as the millions farmers and scientists in the Americas and Asia now growing and developing "GMs" will find themselves at the head of the queue in an innovative industry which will do much to solve the serious problems of population growth, climate change and the loss of fossil fuels. The most severe form of the precautionary principle, which if applied, would stop any developing industry in its tracks, has been adopted by the green movement to target biotechnology. All who read widely and understand the literature on GM technology must now conclude that the probability that with stringent safeguards in place, the possibility that GM foods will harm human beings is extremely remote. No significant environmental damage has so far occurred and it is unlikely that it will.
Jack Pridham, Professor Emeritus School of Biological Sciences Royal Holloway, University of London, Egham, Surrey
Define 'Precautionary Principle' to avoid clashes over biotechnology under World Trade Rules
Need for common approach to assessing risk of biotech-derived products, authors say
- UNITED NATIONS UNIVERSITY, September 15, 2006
Biotechnology-altered foods are the focus of a World Trade Organization ruling scheduled for release this month, a landmark event expected to have a major impact on trade in agricultural products, one of the largest sectors governed by the WTO.
The final report of the WTO Panel in European Communities - Measures Affecting the Approval and Marketing of Biotechnology Products - rules on a dispute founded on differing perceptions about what constitutes legitimate precaution when regulating biotechnology.
Should a country have the unfettered right to refuse trade in such products as genetically-modified grain or hormone-injected beef based on doubts about their safety? Or is such "precautionary" action trumped by World Trade Organization membership obligations?
In other words: when can a nation's interpretation and invocation of "the precautionary principle" be ruled trade protectionism in disguise? And which party should shoulder the burden of scientific proof when the safety of a product is disagreed?
These concerns are prompting a growing number of international trade clashes over the perceived safety of products derived from cutting edge biotechnology and other sciences. Most recently, Japan banned imports of US long-grain rice in August amid reports that traces of a genetically-modified variety had been found in American crops; European Union officials likewise imposed a temporary import ban pending more information. In earlier clashes, Zambia refused a US-AID offer of GM corn over concerns that acceptance would imperil the GM-free status of their exports to the EU. The collapse of the Doha Round means that more of these types of clashes are likely to end up in the WTO.
Averting such conflicts requires a better, common definition and understanding of the "precautionary principle," among other measures, according to the Japan-based Institute for Advanced Studies of the United Nations University. In a report, it calls for international agreement on common approaches to risk assessment and suggests the WTO dispute settlement system is not the "best way in which to resolve disputes in these important areas of policy making."
Prepared by Sabrina Shaw and Risa Schwartz, both professional alumnae of the WTO Secretariat in Geneva, the report warns that disputes over biotechnology products, founded in part on cultural differences, are creating a "trans-Atlantic divide." It highlights similarities and differences between agreements and organizations with respect to precaution - and the consequences of those differences.
According to Gary Sampson, Professor of International Economic Governance at UNU-IAS and author of the recent book, The WTO and Global Governance: "Precaution - not science - lies at the heart of much of the public concern about the regulation of biotechnology products. In the absence of scientific justification for trade restrictive measures, the WTO will increasingly find itself passing judgment on which regulations are 'legitimate' and which are 'unnecessary barriers to trade.' This will put the WTO increasingly between a rock and a hard place to say the least.
"The relative weight assigned to science and societal choice in the determination of standards - or how ''precautionary'' regulations should be - underpins much of the possible future disagreement over the legitimacy of standards relating to genetically modified products within the context of dispute settlement in the WTO," he adds.
"The seriousness of these disputes and the importance of the technology threaten great damage to international cooperation and law," says UNU-IAS Director A.H. Zakri. "More and more commentators are beginning to openly wonder whether the World Trade Organization will be able to survive the full effects of the European Commission -Biotechnology panel, for example."
"How a society chooses to manage the risks of biotechnology will be affected by such factors as confidence in the regulators, acceptance of new technologies, the need for the new benefits and general levels of awareness," says Dr. Zakri.
He notes that several international organizations, often pursuing different objectives, are rushing to regulate biotech, creating "a complex policy and regulatory environment."
The precautionary principle is a central element of several multilateral environmental agreements, a reflection of past instances of underestimated and unanticipated impacts of new technologies - perhaps most famously the industrial release of POPs, a family of organic pollutants subsequently shown to persist stubbornly in the environment - and the use for refrigeration of chemicals later found to destroy atmospheric ozone.
So far, however, the precautionary principle has not been adopted authoritatively beyond international environmental law.
The UNU-IAS report notes differences between Europe and North America are highly pronounced with respect to genetically modified organisms and labeling of GM products, with European concerns about the risks manifested in trade restrictions on biotech goods deemed "acceptable or even desirable in the United States."
Differing perceptions about appropriate levels of precaution for biotechnology was the underlying cause of the WTO dispute where the US and EU disagreed about the safety of beef produced from cattle injected with hormones to bolster their growth. This fundamental difference will drive the US and the EU to the WTO Dispute Settlement mechanism again. US industry has already started lobbying the US Government for a WTO challenge to the EU GM labeling and traceability requirements.
Other earlier disagreements have prevented foods such as unpasteurized European cheeses from entering US markets and past WTO decisions have established that the lack of "absolute certainly" with respect to science cannot be used to justify trade restrictions.
The UNU-IAS report says nations need to determine a common threshold of risk "or, at a minimum, a common practice of risk assessment".
"What is lacking is a uniform description of the precautionary principle in these agreements, leading some critics to argue that the principle is overused without a clear understanding of its meaning and consideration of its implementation," the paper says.
"The flexible definition of the precautionary principle may be its strength, but also one of its greatest weaknesses. Several WTO Members have noted in the Committee on Trade and Environment (CTE) that the difficulty of further integrating precaution in the WTO lies in the lack of an internationally-agreed definition of the precautionary principle."
Says Dr. Zakri: "A clearer understanding of the various uses of the precautionary principle or approach will contribute to a more cohesive and harmonious approach to the regulation of biotechnology at the international level and mitigate some of the damage that is threatened by the current state of affairs."
Says UN Under Secretary-General Hans van Ginkel, Rector of UNU: "There is an important need now to take stock, reassess basic positions, principles and areas of agreement about the precautionary approach before countries initiate a new wave of disputes about biotechnology and the precautionary approach.
"Such a discussion could not be more timely given the recent controversy about genetically-modified contamination of US rice exports, the suspension of the Doha round and the prospect of countries re-examining disputes and grievances in the wake of the upcoming WTO ruling."
The full UNU-IAS report is available online http://www.ias.unu.edu/binaries2/Precautionary Principle and WTO.pdf
New study shows nutrition has greater impact than biotech content on soil organisms
- FARM FUTURES, 15 Sep 2006
Iowa State University researchers find that soil-decomposing bugs are not impacted by the presence of Bt.
After 10 years in the field, biotech corn is still under debate from some quarters. A new study from Iowa State University, released today, offers evidence that the presence of Bt corn in a field has less impact on organisms present than the nutritional quality of the corn itself. The study looked at potential impact of the presence of Bt corn on pillbugs and sowbugs, which play a key role in breaking down corn residues after harvest.
Little work has been done on the potential impact of Bt on such organisms, but other work that has shown Bt can stay in soil for a few weeks after harvest, gave rise to a look at the issue. Researchers looked at Bt lines using the Cry1Ab strain of the insect-controlling bacterium - including Bt11 from Syngenta and Mon810 from Monsanto.
What they found is that pillbugs and sowbugs were not impacted by the presence of Bt in the foliage they consumed. They did discover, in their work, that these decomposers were more likely to be impacted by the nutritional quality of the foliage itself, independent of biotech content.
Previous research on the impact of Bt on soil organisms involved exposing the organisms to Bt directly, which is not what would happen in "the wild." This ISU study actually fed plant material to populations of decomposers and measured weight gain of the bugs. Little Bt was found in the bugs themselves during the test, and any variance in decomposer growth was more directly related to the corn plant, not the Bt.
The researchers say more work is needed on the impact of transgenic plants on the ecosystem, but note this current study shows that the presence of Bt does not affect the survival and growth of the pillbug and sowbug species studied. They advise that the only way to study this issue is to use transgenic plant material "rather than purified protein alone."
The breeder's dilemma-yield or nutrition?
- NATURE BIOTECHNOLOGY, vol. 24, pages 1078-1080 (2006), By Cindy E Morris1 & David C Sands2
1 Cindy E. Morris is at the Unité de Pathologie Végétale, INRA-Avignon, Montfavet 84140, France.
2 She and David C. Sands are at the Department of Plant Sciences and Plant Pathology, 119 Plant Biosciences Building, Montana State University, Bozeman, Montana 59717-3150, USA. firstname.lastname@example.org
The emphasis of traditional crop production on yield is counter-productive for human nutrition.
Plant breeders, challenged to create more nutritious crops, face seemingly radical choices that constitute a 'breeder's dilemma'. In the search for higher yields and lower farming costs, have breeders inadvertently selected for crops with reduced nutritional quality? To create foods that keep pace with our growing understanding of what constitutes healthy diets, plant breeders may need to make a significant shift away from traditional selection criteria. Subsidizing crop nutritional value rather than yield could be an important and economical driver for this shift in perspective.
How healthy is food?
The wide variety and availability of DNA and proteomic tests for human health and disease treatment are among the principal technological consequences of the Human Genome Project. This is leading to a growing understanding about the molecular basis of human health and of genetic predisposition to diseases, such as obesity, type 2 diabetes mellitus, cardiovascular disease and colorectal and other cancers. The pivotal role that diet plays in both the cause and the remediation of these and other health problems is also becoming increasingly clear. Our challenge is to narrow the growing gap between what we should eat to maintain optimal health and the nutritional quality of the staple foods in modern diets.
Plants are a fundamental constituent of the human diet, either as direct sources of nutrients or indirectly as feed for animals. Modern plant breeding has been historically oriented toward high agronomic yield, easy and consistent processing, and disease and pest resistance. This strategy may have unwittingly led to the proliferation of foods that are at the root of certain dietary problems.
The biochemical quality of certain staple plant foods-and not simply the quantities consumed-might be a predisposing factor for obesity and cardiovascular disease. Furthermore, some plants, although efficient as feeds for animal production, may adversely affect the nutritional qualities of animal-based foods. For example, they might not provide sources of certain types of polyunsaturated fatty acids. Creating staple foods that are more nutritious might require selecting crop cultivars that are lower yielding, more sensitive to pests, possess unusual flavors or other uncommon properties, or otherwise do not meet the traditional criteria of plant breeders. Creation of oil crops and animal feeds that enhance the health-promoting quality of animal-derived foods might involve some concerted genetic modification of our current crops or even replacement of traditional canola-, soy-, wheat- and corn-based products with new crops.
Problems with staples
Wheat breeding, for example, has been historically oriented toward increasing yield and the amounts of amylopectin, gluten and protein. Amylopectin and gluten contents ensure baking and processing qualities. After cooking, however, amylopectin (branched starch) is more readily digestible than amylose (straight starch). Results of feeding trials suggest that quickly digested starch, such as amylopectin, promotes the development of insulin resistance in rats. The relatively slow time course of this condition resembles the normal development of insulin resistance in humans1. Insulin resistance is the leading risk factor for type 2 diabetes mellitus and is aggravated by obesity2. In contrast, consumption of high-amylose foods normalizes the insulin response of hyperinsulinemic human subjects. This has potential benefit for diabetics3.
Gluten, the major storage protein in wheat (and similar proteins in barley and rye) causes an autoimmune response that damages the small intestine of certain genetically predisposed individuals. The damaged mucosal lining of the small intestine leads to chronic malnutrition whose symptoms are impaired physical health and emotional state. This genetic disorder is known as celiac disease. According to the US National Institutes of Health Consensus Development Conference Statement on Celiac Disease of June 2004 (ref. 4), this disease has been underdiagnosed by the medical community and may affect as many as 0.5-1% of people in the United States and Europe.
Our staple crops may also have inherent deficiencies that may contribute to emerging dietary problems. Corn is a case in point. About 60% of corn seed proteins consist of prolamins (or zeins) that are almost completely devoid of the essential amino acids lysine and tryptophan. Attempts to select corn lines with enhanced lysine and tryptophan have invariably led to reductions in zein content. The resulting corn lines had soft chalky endosperm and consequently also suffered increased mechanical damage during harvest. They also were more susceptible to diseases and were lower yielding and thus have never led to significant commercial interest5.
Corn-based diets (animal or human) require lysine and tryptophan supplementation for adequate protein synthesis. Tryptophan is also the precursor for the synthesis of some neurotransmitters and for niacin6. Historically, the nutritional deficiency pellagra developed where corn was an important dietary staple and where protein intake was low. It is caused by niacin deficiency due to the absence of its precursor, tryptophan, in the diet. Symptoms are severe dermatitis, diarrhea, dementia and eventually death7. Pellagra is rather uncommon today outside of all but the poorest regions of the world. But in those parts of the world where corn is still an important component of the diet, there may be other consequences of low tryptophan consumption that we are ignoring. The neurotransmitter serotonin, synthesized in the brain from tryptophan, is responsible for feelings of well-being, calmness, personal security, relaxation, confidence and concentration; it is a key player in overall mood and in aggressiveness8 and in the development of depression. Could consumption of tryptophan-rich foods play a role in reducing the prevalence of depression and aggression in society?
Lipids also play an important role in human health from both the standpoint of caloric intake and as a source of essential fatty acids. The ratio of omega-3 to omega-6 polyunsaturated fatty acids in our modern diet has escalated from an optimal ratio of 1:1 or 1:2 to a current ratio of 1:25 to 1:30. This nonoptimal ratio results from high consumption of red meats rather than cold-water fish, a lack of plant sources of long chain omega-3 fatty acids in our diets and the use of animal feeds rich in omega-6 versus omega-3 fatty acids. Development of cooking oils has led to widespread availability of mono- and polyunsaturated oils, such as canola and soy, that have largely replaced saturated fats. Unfortunately, these oils are relatively low in long chain omega-3 fatty acids and high in omega-6 fatty acids. This skewed ratio is a key factor in the prevalence of cardiovascular diseases and inflammatory/auto-immune diseases9, 10. Fish oils, high in long chain omega-3 fatty acids, cannot replace plant-derived oils for widespread use in cooking and feeds. There is a need for crops that can provide abundant quantities of these fatty acids.
It is axiomatic that one of the aims of plant production is the reduction of crop loss from predation and disease. But we wonder if in our efforts to boost yields to feed growing populations we haven't overlooked what pests could be telling us about the nutritional value of crops. Plants and bacteria are the only organisms that can synthesize the full complement of protein amino acids. Animals must consume certain preformed amino acids. The ten essential amino acids are the same for all animals (despite a few exceptions, such as aphids and termites, which harbor bacterial symbionts that can make essential amino acids and furnish them to their hosts11, 12). Nevertheless, plant-derived food that is nutritionally good for insects, rodents, deer and nematodes, for example, is fundamentally good food for humans.
Likewise, many of the compounds that plants produce to inhibit herbivory, such as alkaloids, cyanogenic glycosides, glucosinolates and terpenoids, have wide spectrum activities across the animal kingdom. Furthermore, most animals are equipped with taste receptors and internal feedback mechanisms that allow them to sort through stimuli to obtain necessary nutrients and avoid toxins. Thus, if crops are bred for undesirability to insects could this mean something with regard to the quality of these crops as food for humans? Corn and wheat are both deficient in lysine and methionine and there is some effort to increase the content of these amino acids in these crops. Could this lead to increased desirability to pests? We are not proposing that plant breeding ignore or enhance the susceptibility of crops to pests. Rather, we are pointing out that this is part of the breeder's dilemma in selecting more nutritious crops.
Breeding for yield, fruit size and shelf life has also inadvertently led to changes in the flavor qualities of fruits and vegetables. Tomatoes13 and strawberries14 are well-studied examples. Many of the plant volatiles that contribute to flavor are derived from essential long-chain polyunsaturated fatty acids or essential amino acids. In tomato, virtually all of the major volatiles are linked to compounds that are essential nutrients13. With the exception of volatiles that originate from lycopene (which remain high in tomatoes because of selection for red-colored fruits), flavor components related to essential nutrient have been diminished through breeding13.
Shifting goals for breeders?
What are the technological routes to developing highly nutritious foods, particularly from staple crops? Clearly, genetic and metabolic engineering are likely to be very effective (and in some cases the only possible) routes to modify our current staple crops by insertions of specific genes, gene silencing and immunomodulation. Gene insertion has been used to create rice high in provitamin A15 and gene silencing has led to slight increases in lysine and tryptophan contents of wheat5. Recently, heavy-chain antibodies from llamas have been used to immunomodulate starch branching enzyme A in potatoes, leading to higher amylose content of tubers16.
We also need to seriously consider alternative plant species as candidates for major staple crops. To create gluten-free grain crops or enhance omega-3 production in plants, should breeders focus on genetic modifications of wheat, canola or soy, or could alternative plant species more efficiently and effectively lead to solutions for the associated dietary problems?
To avoid damage of more nutritious crops by pests, breeders might need to design multi-line or composite crops. Each component of these crops might lack a specific nutrient, but the composite would have all of the essential amino acids, for example, in optimal quantities. This might avoid enhancing their desirability to pests.
The route to more nutritious crops might also involve consideration of the full gamut of enlightenment arising from genomics, proteomics and metabolomics as applied to humans, nematodes, insects, plants and other organisms and what these approaches are telling us about the biochemical differences between health and disease. Furthermore, to create widespread acceptance of nutritious crops, breeders may need to bravely address the biology of food addiction and satiation, two very real drivers of food preferences.
Breeders have always confronted dilemmas; it is their stock in trade. The breeder's dilemma we describe arises from the confrontation between the emerging data-driven insights into the physiology of human health and traditional agricultural practices and economics of food production. Wholesale creation of highly nutritious crops may threaten current commodity crops. Solving the breeder's dilemma requires a radical shift in perspective.
Improving our diet is an investment in human capital. It will have important positive spillovers for education and behavior; ultimately, it could improve the quality of life. Can we eventually consider that gains in work time and higher learning performance, for example, are part of the economic results of plant breeding programs? Can an economic system that subsidizes yield be converted to one that, by subsidizing crops with high nutritional quality, concomitantly reduces other costs to society related to human health?
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World Health Org. clears DDT spraying for malaria
- Reuters, Sep 15, 2006
WASHINGTON (Reuters) - DDT, the long-banned insecticide blamed for killing birds and other wildlife, is now approved for use indoors to fight malaria, the World Health Organization announced on Friday.
"One of the best tools we have against malaria is indoor residual house spraying," said Dr. Arata Kochi, director of the World Health Organization (WHO) malaria department. "Of the dozen pesticides WHO has approved as safe for house spraying, the most effective is DDT."
For about $5 per house, indoor spraying with DDT is a cost-effective response to malaria, which kills about a million people annually, most of them children under five.
In parts of Africa and Asia where malaria-carrying mosquitoes spread the disease, 85 percent of home dwellers approached by health workers allow their houses to be sprayed, global health officials said at a news conference.
DDT came into common use in the 1930s as an agricultural insecticide. It became notorious after biologist and ecologist Rachel Carson's 1962 book "Silent Spring" exposed how DDT entered the food chain, killing wildlife and threatening humans.
In 1969, the National Cancer Institute announced findings that DDT could cause cancer, and a U.S. federal ban was imposed in 1972.
Richard Tren, director of the group Africa Fighting Malaria, stressed the difference between agricultural DDT sprayed outdoors and the residual spraying meant to act like a giant mosquito net over individual houses.
"The environmental impact associated with spraying insecticides -- whether it's DDT or other insecticides -- indoors is minimal, it's negligible ... This is as unrelated to 'Silent Spring' as anything," Tren said. "The science is very clear that there are no harmful human effects."
Tren said environmental groups in Africa support its use.
In Washington, the director of the Sierra Club's environmental quality program gave muted backing to the plan.
"Reluctantly, we do support it," said the group's Ed Hopkins. "Malaria kills millions of people and when there are no other alternatives to indoor use of DDT, and where that use will be well-monitored and controlled, we support it."
Hopkins stressed the need for safer alternatives to DDT, "because DDT is not a silver bullet to solve this problem."