Study on Ultra-dried Seed Storage and Cryopreservation of Cunninghamia lanceolata I.Storage Effects on Seed Qualities

The influence of different desiccation temperature on the qualities of Cunninghamia lanceolata seeds was studied by thermal constant temperature desiccation method.The seed quality was tested by germination and vitality experiments for Cunninghamia lanceolata seeds after ultra-dried storage for 1 year and then treated by cryopreservation or by cryopreservation after being pretreated by cryoprotectants with different water contents.It was concluded that the rational desiccation temperature was 50℃, the treated seeds had the highest germination rate and vitality index.3%~5% moisture contents of Cunninghamia lanceolata seeds were the most suitable for ultra-dried storage, and there was no significant difference in tested indexes within this scale of moisture contents after having been stored for 1 year by cryopreservation or by ordinary low-temperature storage.It was showed that the storage effects by cryopreservation was better than ultra-dried storage when the water content was 9%, which might be a good way for long term germplasm storage for Cunninghamia lanceolata.The types and concentrations of cryoprotectants, especially DMSO concentration, would significantly influence on the storage effect by cryopreservation. It was showed that the effects of freezing and thawing method were weakened by cryoprotectants.