Submitted to: Acta Horticulturae
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/15/2013
Publication Date: 6/22/2014
Citation: Volk, G.M., Shepherd, A., Bonnart, R.M. 2014. Strategies for improved efficiency when implementing plant vitrification techniques. Acta Horticulturae. 1039:85-89.
Interpretive Summary: Plant collections that are maintained in field, greenhouse, or screenhouse conditions are vulnerable to environmental disasters or disease infestations. The security of these collections is dependent upon having them backed up in a secure secondary location. Since many horticultural collections are valued for their genetic combinations, they cannot be stored as seeds. For some crops, cryopreservation methods are available so that clonally propagated plant collections can be conserved in liquid nitrogen for extended lengths of time. The process of putting clonal collections into long-term storage is expensive and time-consuming. We describe how long it takes to prepare plant materials, perform the cryopreservation procedure, and then recover propagules from liquid nitrogen storage. We compare the effort required to process propagules collected from tissue cultured plants to those that are collected from the field, greenhouse, or screenhouse. We also compare the time required to assess viability of propagules after liquid nitrogen exposure using two different recovery strategies. This information is useful for gene bank managers who would like to evaluate the labor and time required for implementing cryopreservation techniques to conserve their clonally propagated collections.
Technical Abstract: Cryopreservation technologies allow vegetatively propagated genetic resources to be preserved for extended lengths of time. Once successful methods have been established, there is a significant time investment to cryopreserve gene bank collections. Our research seeks to identify methods that could improve the efficiency of the cryopreservation process. We estimate the labor and time required to cryopreserve shoot tips that are excised directly from field, greenhouse, or screenhouse conditions. We also provide estimates of the time and labor required to introduce propagules into tissue culture, proliferate them, and then excise shoot tips for cryopreservation. Additionally, we provide some estimates for the time it takes to perform a representative cryopreservation procedure. Finally, we demonstrate that micrografting can be used to assess viability after liquid nitrogen exposure when shoot tips cannot be successfully regenerated when placed directly on a culture medium. Although the micrografting procedure is more labor and time intensive, it can also be highly effective.