Cryobionomics: Evaluating the Concept in Plant Cryopreservation

Cryopreservation at ultra-low temperatures is used for the long-term conservation of nonorthodox seeds and the germplasm of vegetatively propagated species. Advances in biomolecular or ‘omics’ technologies are creating a new knowledge base that provides insights into how to solve some of the more difficult cryobiological and conservation challenges. Before routinely implementing cryostorage, it is important to verify that it does not have any genotypic and/or phenotypic destabilising effects and that plants produced from cryopreserved germplasm are true-to-type. The evolving concept of ‘cryobionomics’ considers two practical aspects: (1) the linkage between cryoinjury and stability in vitro and (2) the behaviour and functionality of plants recovered from cryopreserved germplasm once they are reintroduced into natural environments. Cryobionomics is a working hypothesis that explores the emerging research evidence that connects causal factors related to cryoinjury and loss of viability to the risks of genetic instability. This paper presents the principles of cryopreservation and reviews contemporary omics research literature within the conceptual framework of cryobionomics. The aim is to explore the connections between stability and cryogenic/non-cryogenic stress factors with a view to aiding protocol improvement, optimisation and validation for plant genetic resources conservation.

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