Background Seagrass meadows are recognized as critical and among the most vulnerable habitats on the planet. The alarming rates of decline in seagrass meadows have attracted the attention globally. There is an urgent need to develop techniques to restore and preserve these vital coastal ecosystems. So far little work has been done to develop effective long-term storage method for seagrass seeds. The seagrass Zostera japonica Asch. & Graebn is an endangered species in its native range. Here we utilized combinations of different storage times, salinities, and temperature to determine the most appropriate conditions for optimal seed storage. Results Zostera japonica seeds were strongly desiccation sensitive, with a complete loss of viability after 24 h of desiccation. Therefore, long periods of exposure to air should be avoided to minimize seed mortality. In addition, Z. japonica seeds could not endure freezing conditions such as - 5 °C. However, our results indicated that reduced storage temperature to 0 °C could effectively prolong the duration of dormancy of Z. japonica seeds. Seeds stored at 0 °C under a salinity of 40-60 psu showed relatively low seed loss, high seed vigor and fast seed germination, suggesting these to be optimal seed storage conditions. For example, after storage for 540 days (ca. 600 days since the seed collection from reproductive shoots in early October, 2016) at 0 °C under a salinity of 50 psu, seeds still had a considerable vigor, i.e. 57.8 ± 16.8%. Conclusion Our experiments demonstrated that seeds stored at 0 °C under a salinity of 40-60 psu could effectively prolong the duration of dormancy of Z. japonica seeds. The proposed technique is a simple and effective long-term storage method for Z. japonica seeds, which can then be used to aid future conservation, restoration and management of these sensitive and ecologically important habitat formers. The findings may also serve as useful reference for seed storage of other threatened seagrass species and facilitate their ex situ conservation and habitat restoration.

中文翻译：

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濒临灭绝的海草 Zostera japonica 的最佳长期种子储存条件：对栖息地保护和恢复的影响。

背景 海草草地被认为是地球上最重要的栖息地，也是最脆弱的栖息地之一。海草草地以惊人的速度下降，引起了全球的关注。迫切需要开发技术来恢复和保护这些重要的沿海生态系统。到目前为止，在开发有效的海草种子长期储存方法方面几乎没有做任何工作。海草 Zostera japonica Asch。& Graebn 是其原生范围内的濒危物种。在这里，我们利用不同储存时间、盐度和温度的组合来确定最佳种子储存的最合适条件。结果粳稻种子对干燥非常敏感，干燥24小时后完全丧失活力。所以，应避免长时间暴露在空气中，以尽量减少种子死亡率。此外，粳稻种子不能忍受冰冻条件，例如 - 5°C。然而，我们的研究结果表明，将储存温度降低至 0°C 可以有效延长粳稻种子的休眠持续时间。在 0°C 盐度 40-60 psu 下储存的种子表现出相对较低的种子损失、高种子活力和快速的种子发芽，表明这些是最佳的种子储存条件。例如，在 0°C、50 psu 的盐度下储存 540 天（自 2016 年 10 月上旬从生殖枝收集种子起约 600 天）后，种子仍具有相当大的活​​力，即 57.8 ± 16.8%。结论 我们的实验表明，种子在 0℃、40-60 psu 盐度下贮藏可以有效延长粳稻种子的休眠期。所提出的技术是一种简单而有效的长效粳稻种子长期储存方法，可用于帮助未来保护、恢复和管理这些敏感且具有重要生态意义的栖息地形成物。该研究结果还可作为其他受威胁海草物种种子储存的有用参考，并促进其迁地保护和栖息地恢复。