Desiccation-tolerant (DT) organisms can lose nearly all their water without dying. Desiccation tolerance allows organisms to survive in a nearly completely dehydrated, dormant state. At the cellular level, sugars and proteins stabilize cellular components and protect them from oxidative damage. However, there are few studies of the dynamics and drivers of whole-plant recovery in vascular DT plants. In vascular DT plants, whole-plant desiccation recovery (resurrection) depends not only on cellular rehydration, but also on the recovery of organs with unequal access to water. In this study, in situ natural and artificial irrigation experiments revealed the dynamics of desiccation recovery in two DT fern species. Organ-specific irrigation experiments revealed that the entire plant resurrected when water was supplied to roots, but leaf hydration alone (foliar water uptake) was insufficient to rehydrate the stele and roots. In both species, pressure applied to petioles of excised desiccated fronds resurrected distal leaf tissue, while capillarity alone was insufficient to resurrect distal pinnules. Upon rehydration, sucrose levels in the rhizome and stele dropped dramatically as starch levels rose, consistent with the role of accumulated sucrose as a desiccation protectant. These findings provide insight into traits that facilitate desiccation recovery in dryland ferns associated with chaparral vegetation of southern California.

中文翻译：

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正根压对于两种陆地复活蕨类植物的全植物脱水恢复至关重要。

耐干燥性（DT）的生物几乎可以失去所有水分而不会死亡。耐干燥性使生物能够以几乎完全脱水的休眠状态生存。在细胞水平上，糖和蛋白质可稳定细胞成分并保护其免受氧化损伤。但是，关于维管束DT植物中整个植物恢复的动力学和驱动因素的研究很少。在维管束DT植物中，整株植物的干燥恢复（复活）不仅取决于细胞的补液作用，还取决于获得不平等水分的器官的恢复。在这项研究中，原位自然灌溉和人工灌溉实验揭示了两种DT蕨类植物的脱水恢复动态。特定器官的灌溉实验表明，当向根部供水时，整个植物都将复活，但是仅叶片的水合作用（叶面水分的吸收）不足以使碑林和根重新水分化。在这两个物种中，施加于切下的干燥叶状体的叶柄的压力使远端叶片组织复活，而仅毛细作用不足以使远端针状体复活。补液后，随着淀粉含量的增加，根茎和石碑中的蔗糖水平急剧下降，这与积累的蔗糖作为干燥保护剂的作用一致。这些发现提供了有助于促进与南加州丛林植被相关的旱地蕨类植物干燥恢复的性状的见解。而仅毛细血管不足以复活远端针尖。补液后，随着淀粉含量的增加，根茎和石碑中的蔗糖水平急剧下降，这与积累的蔗糖作为干燥保护剂的作用一致。这些发现提供了有助于促进与南加州丛林植被相关的旱地蕨类植物干燥恢复的性状的见解。而仅毛细血管不足以复活远端针尖。补液后，随着淀粉含量的增加，根茎和石碑中的蔗糖水平急剧下降，这与积累的蔗糖作为干燥保护剂的作用一致。这些发现提供了有助于促进与南加州丛林植被相关的旱地蕨类植物干燥恢复的性状的见解。