On the path from xylem hydraulic failure to downstream cell death

编号 040037605

推送时间 20230102

研究领域 森林培育 

年份 2022 

类型 期刊 

语种 英语

标题 On the path from xylem hydraulic failure to downstream cell death

来源期刊 The New phytologist

期 第376期

发表时间 20221028

关键词 Drought;  cavitation;  cell dehydration;  membrane leakage;  relative water content; 

摘要 Xylem hydraulic failure has been identified as a ubiquitous factor in triggering drought-induced tree mortality through the damages induced by the progressive dehydration of the plant living cells. However, fundamental evidence of the mechanistic link connecting xylem hydraulic failure to cell death has not been identified yet. The main aim of this study was to evaluate, at the leaf level, the relationship between loss of hydraulic function due to cavitation and cell death under drought conditions and discern how this relationship varied across species with contrasting resistances to cavitation. Drought was induced by withholding water from potted seedlings, and their leaves sampled to measure their relative water content (RWC) and cell mortality. Vulnerability curves to cavitation at the leaf level were constructed for each species. An increment in cavitation events occurrence precedes the onset of cell mortality. A variation in cells tolerance to dehydration was observed along the resistance to cavitation. Overall, our results indicate that the onset of cellular mortality occurs at lower RWC than the one for cavitation indicating the role of cavitation in triggering cellular death. They also evidenced a critical RWC for cellular death varying across species with different cavitation resistance.

服务人员 孙小满

服务院士 尹伟伦

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