Li Yang, Shi Lei
Key Laboratory of Plant Resources, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, PR China.
Cryobiology. 2014 Jun;68(3):446-50. doi: 10.1016/j.cryobiol.2014.03.002. Epub 2014 Mar 19.
In order to effectively preserve green spores, which have relatively higher water content and lose viability more quickly than non-green spores, we studied the effect of desiccation level and storage temperature on Osmunda japonica spores. The water content of fresh spores was 11.20%. After 12h desiccation by silica gel, the water content decreased to 6% but spore viability did not change significantly. As the desiccation continued, the decrease in water content slowed, but spore viability dropped. For almost all storage periods, the effects of storage temperature, desiccation level, and temperature×desiccation level were significantly different. After seven days of storage, spores at any desiccation level stored at 4°C obtained high germination rates. After more than seven days storage, liquid nitrogen (LN) storage obtained the best results. Storage at -18°C led to the lowest germination rates. Spores stored at room temperature and -18°C all died within three months. For storage at 4°C and in LN, spores desiccated 12 and 36 h obtained better results. Spores without desiccation had the highest germination rates after being stored at room temperature, but suffered the greatest loss after storage at -18°C. These results suggest that LN storage is the best method of long-term storage of O. japonica spores. The critical water content of O. japonica spores is about 6% and reduction of the water content to this level improves outcome after LN storage greatly. The reason for various responses of O. japonica spores to desiccation and storage temperatures are discussed.
为了有效保存含水量相对较高且比非绿色孢子更快丧失活力的绿色孢子，我们研究了干燥程度和储存温度对日本紫萁孢子的影响。新鲜孢子的含水量为11.20%。经硅胶干燥12小时后，含水量降至6%，但孢子活力没有显著变化。随着干燥持续进行，含水量下降减缓，但孢子活力下降。在几乎所有储存期内，储存温度、干燥程度以及温度×干燥程度的影响均存在显著差异。储存7天后，在4°C下储存的任何干燥程度的孢子都获得了较高的萌发率。储存超过7天后，液氮（LN）储存效果最佳。在-18°C下储存导致萌发率最低。在室温及-18°C下储存的孢子在三个月内全部死亡。对于在4°C和液氮中储存的情况，干燥12小时和36小时的孢子效果更好。未干燥的孢子在室温储存后萌发率最高，但在-18°C储存后损失最大。这些结果表明，液氮储存是日本紫萁孢子长期储存的最佳方法。日本紫萁孢子的临界含水量约为6%，将含水量降至该水平可大大改善液氮储存后的结果。文中讨论了日本紫萁孢子对干燥和储存温度产生不同反应的原因。
