An establishment in which both somatic and hereditary genetic material (see germ plasm) are conserved. It stores, in a viable form, material from plants that are in danger of extinction in the wild and cultivars that are not currently in popular use. The stored genetic information can be called upon when required. For example, a crop may be needed that possesses a quality (e.g. tolerance to adverse climatic conditions) which cannot be found in currently exploited cultivars but was present in more antiquated varieties. The normal method of storage is to reduce the water content of seed material to around 4 per cent and keep it at 0°C. (Pollen material may also be used but its longevity is considerably less.) Stored this way, the material often remains viable for 10–20 years. When the desiccating process proves fatal, as is the case with tropi-cal genera producing recalcitrant seeds, where possible the material is maintained by growth. This may require considerable space, but in some cases the problem can be resolved using tissue-culture methods. All stored stock is periodically checked by germination.
Subjects: Plant Sciences and Forestry — Ecology and Conservation.