Deteriorating conditions in the world's crop gene banks pose “a major threat to U.S. agriculture,” which is already losing $20 billion to $33 billion each year to plant pests and diseases.
A new study, published by the University of California Genetic Resources Conservation Program, notes that nearly every major U.S. crop “is battling a plethora of new or re-emerging pests” to which there is little or no resistance.
All major U.S. crops, including soybeans, corn, wheat, rice, potatoes, oranges, and apples, are facing potential threats from pathogens, the report noted, and failure to adequately maintain crop gene bank collections “could constrain agriculture's ability to avert billions of dollars in crop damage.”
These crops, it was noted, depend upon collections of plant diversity in the U.S. and worldwide “to stay one step ahead of pests.”
Collections of crop diversity are also the source of genetic traits needed to improve quality, nutritional value, and yield for crops grown everywhere. But lack of funding has left many of the collections in a state of decay, and “unless addressed, these losses will ultimately threaten agriculture in the U.S. and abroad.”
Just prior to issuance of the report, “Securing the Future of U.S. Agriculture: The Need to Conserve Collections of Crop Diversity Worldwide,” Nobel Peace Prize laureate Norman Borlaug was cautioning that world agriculture is skating on thin ice in terms of a rust epidemic.
“For 52 years, there has been no epidemic of stem rust anywhere in the world,” he said in his keynote address at the USDA's annual Agricultural Outlook Forum 2005 at Arlington, Va.
“Now, we've got a strain in East Africa that, if it gets loose into Asia, North America, South America, or Australia, chances are half of all our grain varieties would be susceptible, and the stage would be set for a disaster of major proportion.
“Just like Asian soybean rust, we've got these new strains that we have to contend with, and that calls for ongoing research. But when you haven't had a major epidemic in 52 years, complacency becomes a problem.
“Soybean rust is here. We don't know a lot about it, but we have to contend with it — and unless we move rapidly, we're likely to learn some bad lessons,” Borlaug said.
Underlying the almost $200 billion value of U.S. agriculture's production at the farm level, is “a little-known resource” — collections of seeds and other living plant material stored in crop gene banks around the world.
The crop diversity report, released at a congressional briefing in Washington Feb. 28, noted that these collections “represent the historic and current diversity of agriculture, without which farming in the U.S. and around the world would stagnate and flounder.”
As pests and diseases threaten to damage or even wipe out entire crop types, and with the markets forever demand new and improved crop varieties, these collections take on added importance to agriculture, said the presenters of the report, Calvin Qualset, University of California Genetic Resources Conservation Program and the University of California, Davis Agricultural Sustainability Institute; Geoffrey Hawtin, Global Crop Diversity Trust; Stephen Smith, Pioneer Hi-Bred International; and Peter Raven, Missouri Botanical Garden and National Medal of Science recipient.
Qualset and Henry L. Shands, director of the USDA/Agricultural Research Service's National Center for Genetic Resources Preservation, were co-authors of the report.
Bombshell for soybeans
The arrival of Asian soybean rust in American fields late last fall “was a bombshell to growers and the soybean industry,” the report noted. “No commercial varieties are resistant to the disease, which can reduce yield up to 80 percent.
“Moreover, a screening of 16,000 soybean varieties from U.S. gene banks has failed to identify a single variety that could be used to quickly breed plants immune to the disease. Thus, the $18 billion U.S. soybean crop faces a formidable foe, with no homegrown source of protection, although resistant varieties may well reside in overseas collections of soybeans.”
Potato blight, of the type that caused the Irish potato famine, has reemerged to threaten the American industry; it is already destroying $400 million worth of potatoes annually.
U.S. corn production, worth $30 billion annually, faces multiple assaults from several diseases, including some that are capable of easily crossing borders and have emerged here.
The $1.8 billion U.S. apple industry is vulnerable to destructive bacteria that cause fire blight disease; they are becoming resistant to pesticides that once controlled them.
The $2 billion U.S. citrus industry is vulnerable to citrus canker and also citrus blight.
Gene banks are also important to the economic health of U.S. agriculture, the report points out, “because they provide American farmers with access to new crop varieties to meet changing consumer needs.” Higher consumer incomes are spurring demand for higher quality foods; an aging population wants healthier foods; and a growing ethnic population is seeking produce once rarely grown on American farms.
“In each case, staying abreast of the market requires access to genetic diversity.”
These same gene banks are essential to improving agriculture and aiding economic development in poor countries, and to jump-starting farming after natural disasters or wars, the Qualset-Shands report notes. “Today, gene bank resources are helping to rebuild agriculture in Iraq and Afghanistan, as well as in countries devastated by the Asian tsunami.”
Another recent study illustrates how central gene banks have become in the ongoing effort to breed improved crop varieties, noting that of 600,000 requests for 20 key crops distributed by the U.S. National Plant Germplasm System in the 1990s, two-thirds sought specific traits — including 37 percent seeking pathogen resistance or tolerance.
“Agriculture requires the broadest possible access to crop diversity,” Shands said. “This diversity is being lost at an alarming rate — in farmers' fields, in the world, and now in the very institutions meant to protect them.”
The report notes that the world's crop gene banks “face mounting stress,” and that only 35 of the 1,470 gene banks around the world meet international standards for managing long term conservation. More than 1 million of the 6 million samples in the collections are degenerating.
A potential solution, Qualset and Shands say, lies in the newly-created Crop Diversity Trust, an independent, international organization established in 2004 to support long term crop diversity conservation.
Initiated by the U.N. Food and Agriculture Organization and the Consultative Group on International Agricultural Research, the trust is building a $260 million endowment through donations from national governments, philanthropic foundations, and private corporations.
“The first priority is to rescue collections that are at risk today,” said Peter Raven. “We need to be collecting, conserving and growing out seeds from around the world. In many cases, the only places plant breeders will be able to find particular genes or combinations of genes will be in gene bank collections.
“Today's farmers rely on such a narrow range of crop varieties that many valuable ones just aren't being cultivated any more. If they're not saved in a gene bank, they may be lost forever, to the great detriment of agriculture and food security.”
The entire report may be accessed and downloaded at http://www.grcp.ucdavis.edu/publications/SafeAgdex.htm 
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