Ex-situ conservation involves the conservation of genetic resources of species away from their area of origin or development. The various ways in which it can be achieved, and their advantages include:
(i) The best method of maximizing a species chance of survival is by relocating part of the population to a less threatened location. Collecting wild and domesticated organisms in botanical gardens, nurseries, aquaria and zoos, etc., are examples of off-site collection.
(ii) Organism are completely protected from predation and poached. They can be monitored and given medical assistance as required.
(iii) Field gene banks are used to conserve genes of perennials, recalcitrant species, vegetatively propagated species, etc., by planting them in an artificial ecosystem requiring more land, adequate soil, suitable weather conditions, etc. For example, orchards, plantations and botanical gardens
(iv) In laboratories (in vitro preservation), tissue culture is used to propagate plants by developing callus, embryoids, pollen grains, shoot tips, etc. Rapid multiplication of endangered plants is possible with this method.
(v) Shoot tip culture maintains virus free plants.
(vi) The gametes, embryos, cells, etc., are preserved at very low temperatures, generally −196°C by cryopreservation, thawed and reused whenever needed.
