异地种子库对于全球植物保护至关重要,特别是像夏威夷这样的热带生态系统中的濒危植物区系。种子库管理者必须最大限度地延长寿命,物种管理者必须在种子失去生存能力之前计划恢复。先前的观察表明,一些夏威夷本地种子在冷冻储存(-18°C)中失去了生存能力。我们调查了夏威夷植物区系中的种子储存行为,以优化储存条件,并建议重新收集间隔(RCI)以最大程度地提高储存种子的生存力。
使用20多年的实时种子储存活力数据,我们测试了197个物种的冷冻敏感性,并计算了295个物种的RCI。使用在5°C和-18°C下储存>2年的种质的配对测试,我们开发了一个相对性能指标来确定冻结敏感性。我们计算了最高发芽率(P70)的70%的RCI。
我们确定了四个科(Campanulaceae,莎草科,茜草科,和荨麻科)和具有种子冷冻敏感性的四个属和具有可能的冷冻敏感性的另外六个属。储存寿命是可变的,但195个物种在最近的测试中(1到20+年)的生存力>70%,123种RCI>10年,45种RCI<5年。
在夏威夷比任何其他区域植物区系更广泛地观察到冻结敏感的储存行为,也许是由于其他地方的测试不足。我们提出了一种测试种子冷冻敏感性的新方案,这通常是不明显的,直到2-5年的存储。重新收集间隔将指导夏威夷的恢复实践,结果为全球的种子保护工作提供信息,尤其是热带和亚热带地区。
Ex situ seed banking is critical for plant conservation globally, especially for threatened floras in tropical ecosystems like Hawai\'i. Seed bank managers must maximize longevity, and species managers must plan restoration before seeds lose viability. Previous observations suggested some native Hawaiian seeds lost viability in frozen storage (-18°C). We investigated seed storage behavior in the Hawaiian flora to optimize storage conditions and recommend re-collection intervals (RCI) to maximize viability of stored seeds.
Using 20+ years of real-time seed storage viability data, we tested freeze sensitivity for 197 species and calculated RCIs for 295 species. Using paired tests of accessions stored >2 yr at 5°C and -18°C, we developed an index of relative performance to determine freeze sensitivity. We calculated RCIs at 70% of highest germination (P70).
We identified four families (Campanulaceae, Cyperaceae, Rubiaceae, and Urticaceae) and four genera with seed freeze sensitivity and six additional genera with likely freeze sensitivity. Storage longevity was variable, but 195 species had viability >70% at the most recent tests (1 to 20+ yr), 123 species had RCIs >10 yr, and 45 species had RCIs <5 yr.
Freeze sensitive storage behavior is more widely observed in Hawai\'i than any other regional flora, perhaps due to insufficient testing elsewhere. We present a new protocol to test seed freeze sensitivity, which is often not evident until 2-5 years of storage. Re-collection intervals will guide restoration practices in Hawai\'i, and results inform seed conservation efforts globally, especially tropical and subtropical regions.