A crop genebank is a facility for conserving, managing and reproducing the diversity of crop varieties and their wild relatives. Like the crops they conserve, genebanks come in may varieties, from massive collections stored in elaborate buildings to a simple field of a few labelled plants. All have as their primary purpose the safe maintenance of plant diversity. That may be the diversity of a single species and its wild relatives, for example the 80 000 or more samples of rice and its relatives, gathered from around the world and maintained by the International Rice Research Institute in the Philippines. Or it could be a small collection of a few locally important fruit trees, like those being assembled by schoolchildren in Sarawak.

One reason to conserve crop diversity in genebanks is that it is under threat elsewhere. Habitats continue to be destroyed by unsustainable human activity, and with the habitats go the plants. One of the threats to diversity is advanced agriculture. As new varieties become available, and are taken up by farmers because they offer genuine benefits, they may displace the diversity that was there before. This is especially ironic because all advanced breeding is built on existing diversity, which makes it imperative that this diversity be conserved and remain available somewhere.

Meeting the needs of breeders is thus another important function of genebanks. But increasingly genebanks are fulfilling additional roles. In the aftermath of disaster, natural and man-made, they are a repository not only of the seeds farmers need, but also of essential skills and knowledge. As the genebanks of the Future Harvest Centres in particular gain more experience of responding to wars, hurricanes, drought and disaster, so their response becomes more effective, helping to put agriculture back on its feet as quickly as possible.

Support for long-term caretaker activities can be precarious and difficult to justify, especially from a narrow-minded and short-term economic standpoint. Yet when it comes to rebuilding a shattered country’s economic base, or when a single sample among 50,000 contains exactly the traits that farmers need, the value of genebanks is almost literally impossible to calculate.

Some people may choose not to insure their possessions, which is fine if they are easily replaced and their children have no expectations. Crop diversity, once lost, is impossible to replace. That is why we must pay the premiums needed to ensure that humanity continues to have access to a well-managed global system of genebanks.