This study was conducted to improve and supplement the system of cryopreservation for adventitious bulbs induced by tissue cultured bulb-scales of lily (Lilium spp.) cvs. ‘Milky way’. The explants, bulblets and bulb-scale-bulblets, were treated to low temperature (4℃) for 7 days prior to the pre-culture. The adventitious bulbs were pre-cultured in Murashige and Skoog (MS) liquid medium supplemented with sucrose (0.3 and 0.7M). The pre-cultured adventitious bulbs were treated to loading solution (LS1 or LS2, C4 or C6) containing 35% of PVS3 (LS1, C4) or 40% of PVS3 (LS2, C6) for 40 min and exposed to dehydration solution (PVS3, B1) containing 50% glycerol and 50% sucrose for 60 min at 25℃. The adventitious bulbs were moved onto droplets containing 3 μl PVS3 on sterilized aluminum foils, and then soaked into liquid nitrogen (LN) for 60 min. The result of highest regrowth rate as 65.7% was obtained in cold treatment (4℃), osmoprotected with LS1 solution, and cultured in PCM3 medium by using bulb-scale-bulblet for cryopreservation. This result shows that droplet-vitrification could be used as a promising method for long-term storage of lily genetic resource.

Abstract
Introduction
Materials and Methods
    Plant material
    Cold hardening based on different tissues and preculture
    Loading and dehydration procedure for cryopreservation
    Unloading procedure and plant regrowth
    Evaluation of survival and regrowth rates
Results and Discussion
    Differences in cold-hardening according to tissues
    Effects of loading solutions on survival and regrowth ratesfrom cryopreserved bulblets
    Effect of post-culture media on survival and regrowthrates from cryopreserved bulblets
References

• Jae-young Song(National Agrobiodiversity Center, NAS, RDA)
• Young-yi Lee(National Agrobiodiversity Center, NAS, RDA) Corresponding author
• Jung-yoon Yi(National Agrobiodiversity Center, NAS, RDA)
• Jung-ro Lee(National Agrobiodiversity Center, NAS, RDA)
• Mun-sup Yoon(National Agrobiodiversity Center, NAS, RDA)