Submitted to: Acta Horticulturae
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/13/2021
Publication Date: N/A
Interpretive Summary: Plant cryopreservation methods are implemented in genebanks to conserve plant genetic resources for extended lengths of time. There are many examples in the literature describing methods for successful cryopreservation of shoot tips from fruit crops. This paper describes the testing and use of mint, strawberry, and kiwifuit shoot tip vitrification and droplet-vitrification methods within the USDA National Plant Germplasm System at the National Laboratory for Genetic Resources Preservation in Fort Collins, Colorado. Information is also provided about a new website (https://grin-u.org/) that has educational resources demonstrating cryopreservation procedures with text, images, and videos. The eBook titled "Training in Plant Genetic Resources: Cryopreservation of Clonal Propagules" is freely available online.
Technical Abstract: Genebanks conserve vast collections of plant genetic resources that are maintained as seeds, plant tissue cultures, and actively growing plants in the field and greenhouse. These collections must be securely backed-up at secondary locations. Cryopreservation technologies have been developed to place dormant buds and shoot tips into liquid nitrogen, which minimizes the long-term costs of safety duplication. Although there are many published methods in the literature, it can be challenging to directly use those methods for routine processing of genebank materials. This may be because of the variation in lab-to-lab operations or the source and genotypes of the specific taxa that are processed. We have recently tested previously established shoot tip cryopreservation methods for Fragaria (strawberry), Mentha (mint), and Actinidia (kiwifruit) to determine if they could be used with no or minimal modification in our program at the National Laboratory for Genetic Resources Preservation in Fort Collins, Colorado. We found that the Fragaria and Mentha methods could be easily adopted and that the Actinidia method was suitable with minor modifications. We have developed online educational resources at a new website (https://grin-u.org/) in the form of chapters in a freely available eBook titled “Training in Plant Genetic Resources: Cryopreservation of Clonal Propagules” (https://colostate.pressbooks.pub/clonalcryopreservation/), to demonstrate the shoot tip cryopreservation process for Fragaria, Mentha, and other horticultural crops. The advantage of this educational platform is that text, images, videos, and downloadable protocols are packaged in an online resource that can be viewed by students, technical staff, as well as researchers.