Why build an ark for seeds?

4 November 2011

Last month, the National Science Foundation awarded a group of plant evolutionary biologists $1.2 million to spend the next 4 years collecting and banking seeds that won’t be used until 5, 10, or even 50 years from now. Proponents of the new effort are betting that the next generations of evolutionary biologists will be eager to break into this time capsule.  Comparing plants grown from the stored seeds with plants collected decades from now will allow researchers to look more objectively at how a species reacts to global warming, species invasions, new land-use patterns, or other changes in their surroundings.

Seed banks, libraries of botanic genetic blueprints if you will, have existed since at least 6750 B.C. with the first recorded seed banks occurring in Mesopotamian mountains which are present-day Iraq.  The first banks were little more than temple granaries.  But over the last five years the effort has gone ‘hi tech.’  There are currently about 1,400 seed banks around the world, but the most famous is the Svalbard Global Seed Vault,  located on a remote Norwegian island in the Arctic Svalbard archipelago opened in February 2008.

The oldest is the Vavilov Institute of Plant Industry which was established in 1894 in St. Petersburg.  Nikolai Vavilov, for whom the institute is named, was a Russian biologist and plant breeder. Vavilov was one of the first scientists to understand the importance of crop diversity and played a major role in raising awareness of the importance of genetic conservation. The institute is the only facility of its kind in Russia with a global collection containing hundreds of thousands of specimens

Also known as the Doomsday Vault, it functions as a global repository and backup for all other seed banks.  Built to protect the world’s food supply in the event of a global crisis, it was constructed high enough to avoid rising sea levels, is kept at a constant zero degrees with refrigeration powered by local coal, it was dug in deep enough into the mountain to be able to withstand a nuclear explosion, and if the power runs out, it will be weeks before the internal temperature of the vault will reach anything near to menace it’s contents.

Out of the 7,000 species of plants currently used for agriculture around the planet, only 30 crops make up the world’s diet. Wheat, corn and rice alone account for more than half of the world’s food consumption.  Right now, for example, our wheat supply is dwindling. The world’s stockpiles are at their lowest numbers in thirty years. Consumption is exceeding production, and farmers are having a tough time keeping up. Experts predict this trend is temporary.

But what if it’s not? Or, what if a natural disaster wipes out the majority of wheat and other important crops?

Seed banks are like a savings account. Seeds are “deposited” into secure storage with the intention of “withdrawing” them in the future when they are needed.  When stored correctly, seeds can remain viable for decades or even centuries.

Difficult-to-store seeds may respond better to cryopreservation, or in-vitro storage. For example, the banana plant doesn’t produce seeds, so alternative storage methods are necessary. In-vitro storage means that living plant tissues are stored, rather than seeds. Scientists then place these living tissues in liquid nitrogen — around minus 320 degrees Fahrenheit (minus 196 degrees Celsius) — to ensure better long-term storage [source: Bioversity International].

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Although shelf life varies from crop to crop, most seeds can survive in cold storage for decades and some even longer. Eventually, though, all seeds will die. Before this happens, scientists remove seeds from storage and plant them to harvest and re-bank fresh seeds.

With all these seeds in storage, who gets ownership of the seeds? Usually the owners of the seed banks control their own seeds. But in the case of the Svalbard Vault in Norway, depositors retain possession rights of the seeds they place in the bank.  Of course, these ownership rights don’t preclude one country lending seeds to another country in need.

Back then, seed banks protected seeds from animals and extreme weather. Today, we store seeds for different reasons. The most essential reason is crop diversity. Just as humans have specific genetic traits, so do plants. And just as humans have evolved and adapted to specific conditions over time, so have plants. Different varieties of plants are suited for different things.  This sort of diversity must be preserved — not because we need 50 varieties of popcorn, but because we don’t want to lose any plants that may prove valuable in the future. For example, in the 1970s a widespread fungus cut United States corn yields in half. The blight was alleviated by use of genetic materials from a wild corn relative that was fungus-resistant.  Aside from crop diversity, other reasons include climate change, natural disaster, disease, man-made disaster and research.

Aside from assuring a future genetic patrimony, research may be the most important.  One in every six wild plants is used for medicinal purposes. Who knows what diseases the right plant or herb could eradicate?

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