What happens when natural diversity disappears is etched into history by the Irish Potato Famine of the 1840s. Nearly 2 million people starved to death because not a single potato variety could survive an attack of Mexican potato blight.
U.S. crop disasters have been less tragic, but they serve up a reminder that hardly a food or fiber plant grown today is native to this country. That makes seed banks that stand between farmers and pest-related catastrophe more important than ever as the guardians of modern-day agriculture.
"Our mission is to preserve and provide inherent genetic variation that can be mined later," says Candice Gardner, research leader of USDA’s North Central Regional Plant Introduction Station in Ames, Iowa.
"Whether germplasm is old or recently created, including materials with expired patents, it is of limited value without genetic and phenotypic information to inform us on its properties and traits of value. Phenotyping is hard work and expensive, but it is important to provide information to researchers," Gardner says. The nation’s corn germplasm is banked and studied in Ames, along with several other crops.
A big component of the current mission is to make germplasm available to scientists searching to find traits now deemed valuable.
Randy Nelson, curator of the USDA Soybean Germplasm Collection in Urbana, Ill., keeps a collection of public and privately released varieties, which is useful for research.
Seed banks also get involved in the effort to head off pending agronomic problems. One example is the current effort to find genetic wheat resistance to the potentially devastating Ug99 stem rust discovered in Africa in 1999, says Mike Bonman, research leader for the National Small Grains Collection in Aberdeen, Idaho.
"We are screening our collection of 20,000 spring wheats in Kenya for resistance," he says. "The wheat population doesn’t have a lot of resistance. That’s why we’re involved.
"Half of the 20,000 spring wheats are landraces developed by farmers and collected during the past 100 years. We are finding that some are showing resistance to Ug99. The next step is to incorporate the resistance from these materials into modern varieties. We can only do one main season a year of these, but we’re trying to use modern molecular techniques to speed things up," Bonman says.
Safe and secure. These three seed banks are part of a network of 27 repositories in USDA’s national plant germplasm system. Each focuses on certain plants.
The National Center for Genetic Resources Preservation in Fort Collins, Colo., serves as a backup site. The center stores plant seeds and animal semen in a facility designed to be secure from nuclear and terrorist attacks.
In Fort Collins, researchers also investigate what untapped genes might be usable, sample them, keep the history of where they were collected and investigate genetic bottlenecks that might inhibit research. The center currently has about 475,000 seed accessions stored in a liquid
nitrogen condition designed to keep them viable for the next 1,000 years.
The U.S. is not alone in its concern about protecting and evaluating seed. About 1,400 seed banks operate worldwide, according to USDA. In recent years, the Global Crop Diversity Trust and the government of Norway developed the Svalbard Global Seed Vault, located on a cold mountainside.
Touted as the ultimate backup facility, the vault houses 500,000 entries from around the world.