A Study on the Use of Vitrification–Dehydration Method as a New Protocol for In-vitro Cryopreservation of Date Palm Shoot Tip Cultivars

Over the past 40 years, scientists have developed and tested a range of cryopreservation techniques for preserving plant cells and tissues, but the routine storage of plant germplasm other than seeds in liquid nitrogen (LN) is a relatively new practice. The main objective of this study was to collect and preserve the germplasm of the date palm cultivars in vitro. This study evaluated the in vitro preservation and genetic stability of date palm shoot tip explants using dimethyl sulfoxide (DMSO) in the medium for long-term storage. This study was conducted using two data palm cultivars ‘Khalass and Sukari’. Shoot tip explants of about 2-3 cm in length were excised from in vitro cultures and were transferred to preservation media. The genetic similarity was calculated using the average linkage between groups. The results showed that the highest rates of survival (80%) and recovery (75%) were observed with 1.2 M sucrose. To determine the effect of vitrification on freezing tolerances, cultures were exposed to a solution that dissolved the glaze for 60-80 minutes. The maximum survival rate obtained with exposed cultures was 85%. RAPD (randomly amplified polymorphic DNA) was used to explain the differences in the genetic characteristics of cryogenic tissue cultures and non-cryogenic tissues of date palm. Both were similar to the germinated date palm in the open field. Finally, the cryopreserved plants were able to adapt to free-living conditions after acclimatization. All aspects will contribute to the improvement of the currently available techniques for the in vitro germplasm conservation of date palms. RAPD (randomly amplified polymorphic DNA) was used to explain the differences in the genetic characteristics of cryogenic tissue cultures and non-cryogenic tissues of date palm. Both were similar to the germinated date palm in the open field.