VITRIFICATION/ONE-STEP FREEZING PROCEDURE FOR CRYOPRESERVATION OF PERSIMMON DORMANT BUD

The cryogenic technology can be regarded as an important biotechnological approach, offering unrivalled opportunities for cost-effective long-term germplasm preservation of plants. New cryopreservation techniques are now available, aiming at the direct immersion in liquid nitrogen (“one-step freezing”) of explants, with a considerable simplification of procedures. This technology is based on the induction of cell vitrification during a very fast decrease of their temperature and in this report it has been applied on shoot tips, excised from dormant buds of Diospyros kaki. Shoot tips of cvs. ‘Hirathanenashi’ and ‘Triumph’, showed a survival of 86% and 80%, respectively, after they were incubated at 25°C in the Plant Vitrification Solution (PVS2) and plunged in liquid nitrogen. Afterwards, in order to validate the procedure for the preservation of this germplasm, the RAPDs analysis was carried out to ascertain the genetic stability of the cryopreserved shoots.