RESUMEN
The source of germplasm as well as the technique used for storage of mosses can enhance survival after cryopreservation. Samples of gametophores, protonemata and protonemal brood cells from in vitro cultures of Splachnum ampullaceum were cryopreserved following exposure to a plant vitrification solution (PVS2) for two different times (5 and 10 min) at 0 degree C. Half of the samples were pretreated with a loading solution containing 2 M glycerol and 0.4 M sucrose before exposure to PVS2. After one week storage in liquid nitrogen, S. ampullaceum samples were regenerated on Gamborg's B5 mineral medium with B5 vitamins. Exposure to a loading solution was a prerequisite for high survival in all samples. Four weeks after cryopreservation, 92.3 percent brood cells, 60.0 percent gametophores and 46.0 percent protonemata pretreated with a loading solution had regenerated, displaying normal growth and development, thus demonstrating that vitrification is a useful method for moss cryopreservation.