Methods of Seed Storage

Seed storage methods range from simple traditional structures to highly controlled modern facilities. Conventional storage uses bamboo structures, mud or earthen structures, wooden structures and underground structures; at the village level, seed is also stored in bulk in concrete or cement silos, and in metal or plastic drums, while improved rural storage structures include the coal-tar drum, the Udaipur bin, the bamboo bin, the Pusa bin and various metal bins. Modern methods offer far greater control and longevity. Cryopreservation stores cells, tissue, embryos or seed at ultra-low temperature in liquid nitrogen at -196 degrees Celsius; it is not practical for routine commercial seed storage, but it is invaluable for preserving valuable germplasm for future use in ways that conventional storage cannot match. Gene banks preserve seed under carefully controlled temperature, relative humidity and seed-moisture conditions, with containers and arrangements varying by seed type, to extend viability over long periods. The Svalbard Global Seed Vault (Figure 9.17) represents the most extreme version of this approach: seeds are sealed in four-ply envelopes, placed in plastic tote containers on metal shelving, and kept in underground storage rooms at about -18 degrees Celsius, where the low temperature and restricted access to oxygen keep metabolic activity low and delay seed ageing, while the surrounding permafrost helps maintain that low temperature even if the electricity supply fa …