Cryopreservation of azalea by encapsulation-dehydration

There is an azalea collection, with more than 600 accessions, at the Department of Plant Genetics and Breeding. In order to maintain this collection in an efficient and economical way, new preservation strategies are required, and this is the subject of this paper. Preliminary results show the usefulness of an encapsulation-dehydration technique to cryopreserve azaleas. Shoot tips of in vitro micropropagated plants were precultured on culture medium with high sucrose concentration, subsequently encapsulated (beads contain sucrose and glycerol), dried and frozen by direct immersion in liquid nitrogen. 41.7% of the cryopreserved shoot tips regenerated into fully-grown plants in vitro and in vivo. Further research is needed to evaluate the genetic and epigenetic stability of the regenerated plants. In particular the sporting of cryopreserved material needs further investigation