In Vitro Active vs. Field Genebank Maintenance of Sweet Potato Germplasm: Major Costs and Considerations

Abstract

Increased public concern for the preservation of plant genetic diversity has resulted from a growing awareness that agricultural productivity and stability ultimately depend on plant resources that are native to a relatively few countries and that many of these plant genetic resources are threatened with extinction (Fitzgerald, 1988). Many plant genetic resources are not renewable. Conservation efforts are driven by pragmatic, concerns for the need to conserve and use plant genetic diversity to help alleviate global hunger and by an increasing recognition of our obligation to conserve these resources for future generations (Christensen, 1987). The continuing loss of the world’s biological diversity has prompted several international organizations, most notably the International Board for Plant Genetic Resources (IBPGR), to organize national and international programs aimed at assembling and maintaining collections of crop germplasm. Success in this area has been impressive (Plucknett et al., 1987). However, as collections continue to increase in size and number, so do problems associated with the logistics of efficiently preserving these plant materials in a manner such that they are both secure from loss and yet available for use in crop improvement programs. To ensure both the security and the availability of crop germplasm, a two-tier system of management has been adopted. Ideally, there exists for each crop a “base” and an “active” collection (Williams, 1984). The base collection is the vehicle for long-term conservation. Accessions in base collections are not intended for distribution. Major emphasis is placed on providing maximum security against loss, with little regard for availability. Active collections are the ve-