Optimization conditions for cryopreservation of Nelumbo nucifera Gaertn., aquatic plant

This study was conducted to find the optimal cryopreservation conditions for efficiently preserving the genetic resources of the aquatic plant lotus (Nelumbo nucifera Gaertn). The seed viability differed depending on the type of vitrification treatment agent, and the longer the PVS2 treatment time, the lower the viability. Among the treatments, T1 (2M glycerol) and T7 (Loading solution + PVS2) were the treatments that showed viability rates similar to those of the control (92.1 +/- 5.95%). When the seeds were stored for 12 weeks, the viability rate of the control dropped to 0%, but the treatments T1 and T7 were maintained unchanged. The change in the germination rate of seeds according to the storage period, the control was 0% after 4 weeks. In the case of the treatments, T1 showed a high germination rate in the 1 day (86.67 +/- 6.67%), but after 12 weeks, a lower germination rate (54.67 +/- 5.58%). On the other hand, T7 had a slightly lower initial germination rate of 73.33%, but it was maintained even after a prolonged storage period. The shoot growth of the cryopreserved sprouted seedlings was lower than that of the control, and there was no morphological difference, as T7 was the best among the treatments. As a result of RAPD analysis using seedling primers, no genetic variation was found. The above results are expected to be widely used not only for treatment but also for the conservation of genetic resources of other aquatic plants.