Gene banks and agriculture

You've probably heard of heirloom tomatoes. They're becoming increasingly popular because they offer interesting alternatives to the typical beefsteak tomato.¹ Heirloom varieties are just one example of the interest gardeners increasingly show in conserving some of the great variety of fruits and vegetables that have been grown. But gardeners' efforts are only a small part of the story.

Congress established a system of repositories after World War II to maintain and distribute plant genetic resources. This resource has now grown into the National Plant Germplasm System (NPGS; http://www.csrees.usda.gov/nea/plants/in_focus/pbgg_if_npgs.html) and consists of 26 repositories with approximately half a million individual collections. The NPGS functions to maintain agricultural biodiversity and ensure the preservation of the genetic resources needed for food security and environmental restoration.
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There is little doubt that plant genetic resources are needed to address today's problems. Yet the erosion of plant biodiversity continues a decline that had already begun even as Frank Meyer traveled the globe in search of botanical resources to benefit society. Seed bank collections serve as insurance against unanticipated future threats to food security, the degradation of our environment, and the loss of plant biodiversity. The WRPIS, as part of the US network of plant gene banks, provides a vital link in an emerging world system aimed at maintaining, conserving, and utilizing these precious plant genetic resources, the seeds of our future. (R.C. Johnson, PloS Biology)