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In the late 1990s, the Australian chickpea industry fell victim to a fungal disease called ascochyta blight. Field after field of chickpea crops were devastated.
Plant breeders went to work, scouring the world for seeds with a natural resistance to the blight. It took years to develop a chickpea variety that could withstand the disease, but the crop eventually recovered.
"This is an absolute classic example of where a food crop was wiped out," says Tony Gregson, the chairman of Bioversity International (formerly the International Plant Genetic Resources Institute) based in Rome, and also an Australian farmer who witnessed it firsthand. "Imagine what would happen if [a crop as important as] wheat is wiped out," he said.
Also based in Rome is the Global Crop Diversity Trust. Its job is to prepare for even more frightening scenarios, and it is protecting food security by conserving crop diversity. With crops under serious threat from human development, ever-evolving diseases and climate change, the stakes are high.
Cary Fowler, the trust's executive director, knows the challenges. He travels the world to protect our crops – an often thankless job, but one of utmost importance. He is helping collect seeds to store in the Svalbard Global Seed Vault in Norway (see, Doomsday vault opens for business).
Nicknamed the "doomsday vault", the facility is built 130 m down inside an Arctic mountain. With its remote location and constant cold temperatures, the vault is designed to outlast anything from a nuclear blast to severe climate change.
Even under the most disturbing possible scenarios for global warming, the seeds will remain naturally frozen for up to 200 years. This seed sanctuary is crucial in the battle to conserve crop diversity, says Fowler, pointing to the example of the chickpea blight.
The Australian farmers planted what they believed to be the highest quality crops, and they were at the time, says Fowler. No one saw the ascochyta blight coming. "The world changes… pests and diseases slowly evolve, and today's best is tomorrow's lunch."
The lesson? Plant breeders must be prepared for anything. "No one has a perfect crystal ball, so we don't know what's coming next," Fowler says. "We just know that something is coming."
For plant breeders to successfully combat this uncertainty, they need to have a wide range of crop varieties at their disposal. Within each crop type, there is incredible diversity. Wheat alone has 200,000 distinct varieties, corn and chickpeas have 30,000 each, and even peanuts have 15,000.
Each variety has a different combination of genes, and some of the corresponding traits – including heat-, drought- and disease resistance – could be highly useful in the future. It's impossible to know which ones will be required, however, and any variety could end up being important.
(One notable exception is the banana, most of which worldwide are asexual clones of the same variety, the Cavendish. This is a worrying problem for experts, as there is no reservoir of genes to dip into to help it fight new diseases – or for farmers to easily breed new varieties.)
Some of these many varieties of crops are vanishing, due to a combination of natural and man-made dangers – and also, sometimes, because they go out of fashion. The rate of loss will only increase, Fowler says, as climate change continues to take its toll on the world's plants.
"We think the effects are going to be fairly dramatic in short order," he says. By 2030, climate change could cause serious problems for agriculture production – and that is only two breeding cycles away.
To best prepare agriculture for climate change, and all of the other threats, conserving crop diversity is critical. And that's where the Svalbard Global Seed Vault comes in.
Conserving diversity requires safeguarding all the seeds from different crop varieties. About 1,400 seed banks, also called genebanks, currently house around 6.5 million seed samples across the world. However, their security is by no means guaranteed.
Seeds must be stored at cold temperatures, preferably -18°C, to preserve their viability. A simple equipment malfunction could render seeds useless. For example, a weekend power outage in Cameroon destroyed an important tuber collection.
In addition, seed banks are vulnerable to both human and natural disasters. Seed banks in Iraq and Afghanistan were destroyed during warfare. A bank in the Philippines was seriously damaged during a typhoon. "You can never quite anticipate where the next disastrous situation or catastrophe will be," Fowler says.
The trust therefore saw the need for a backup facility. "Insurance policy" is the term Fowler likes to use. In 2003, they began to develop plans for a more impenetrable type of seed bank. In February 2008, Svalbard opened its doors.
Other genebanks can send backup copies of their seeds to Svalbard for safekeeping. The idea is to protect the word's food sources by providing a refuge for genetic diversity. "It's an absolute treasure trove of character traits that will be important, perhaps even critically important, to agriculture in the future," he says.
The vault has a capacity of 4.5 million samples, or 2.25 billion individual seeds. At its one-year anniversary, Svalbard held 400,000 unique seed samples. Fowler and others like him are still travelling the world on a rescue mission: save the seeds of as many crop varieties as possible.
The task has taken Fowler all over. His favourite place has been Ethiopia, where many of the crops have special drought-resistance and high nutritional qualities. "It's one of the most interesting countries in the world from a crop perspective," he says.
He estimates the rescue project will take another two years to complete. One of the biggest issues is picking places to search for new varieties. The trust is developing models that help pinpoint areas where useful wild varieties are most likely to grow. The models take into account current conditions, as well as climate change expectations.
They also want to make it easier for plant breeders to locate the traits they require. "There's no such thing as a Google or Amazon for a plant breeder," Fowler says. "They have to go genebank by genebank."
Plant breeders are few in number. For example, there are only six banana breeders in the world. The Trust would like to create a database to allow this small group to quickly search for desired seeds: "one-stop shopping," says Fowler.
"We won't get a lot of kudos or press coverage for that," he continues, "but the plant breeder knows how important it is and farmers will know the difference."
The same problem applies to the trust as a whole: it's easy to overlook a body devoted to collecting and cataloguing seeds. But Fowler knows how important their task is. "It's essential that [the seeds] exist if we want anything resembling food security in this world," he says.
Lisa Merolla is a science writer based in Boston, USA.
