E.R.J. Keller, A. Senula, C. Zanke, M. Grübe , A. Kaczmarczyk
Cryopreservation, storage of genetic material in or above liquid nitrogen, is the safest and most cost-effective method to maintain vegetatively propagated plant germplasm and such species, which possess recalcitrant seeds. Experience has been accumulated in many species. Along the main line consisting in explant trimming, dehydration, cryoprotection and temperature reduction several parameters can be variegated. Active reactions of the tissue prior to cryopreservation treatments may be used, such as cold adaptation. Dehydration conditions and cooling speed are other important factors. Finally repair of cryo-injury and regeneration must be investi-gated. Using these basic components several methods were developed, such as dormant bud method, two-step freezing, vitrification, encapsulation and various droplet methods, also in combination. Although being suitable for most targeted species, considerable differences were found in success rates depending on genotype and presence of endophytes. In vitro storage uses slow growth methods for medium-term preservation. These methodical surroundings to cryopreservation can also be used in parallel to it, especially when material is more often requested. Genebanks need to maintain highly diverse collections and cannot focus on well-investigated model organisms. Therefore, logistic questions are important and considerations concerning regeneration probability, storage safety and economy. Various scenarios can be followed depending on given situations like highly safe storage of important material or emergency rescue in case of acute danger of loss. It is also necessary to assess relations of storage and request frequency. Finally, cryopreservation and in vitro culture methods can also be potential contributions to store seed-producing populations in case of limitations in true-seed reproduction. Criterion for success is safe maintenance of healthy and genetically unchanged germplasm. At present, the genebank of IPK Gatersleben maintains 1307 accessions in cryopreservation, mainly of potato, garlic and mint. The characteristics of in vitro storage and cryopreservation are exemplified using the experience with these crops.
Keller, E.R.J., Senula, A., Zanke, C., Grübe , M. and Kaczmarczyk, A. (2011). CRYOPRESERVATION AND IN VITRO CULTURE - STATE OF THE ART AS CONSERVATION STRATEGY FOR GENEBANKS. Acta Hortic. 918, 99-111
DOI: 10.17660/ActaHortic.2011.918.11
germplasm preservation, long term storage, storage methods, endophytes, genetic stability, storage safety, storage economy

Acta Horticulturae