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bioRxiv · 10.1101/531632

A new mechanism for tree mortality due to drought and heatwaves

Cochard, H.
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Abstract

AO_SCPLOWBSTRACTC_SCPLOWPlants tend to die earlier in hot and drought conditions, but the underlying mechanisms are not yet understood. I propose here a new mechanism by which excessive residual water losses caused by high cuticular permeabilities and a high leaf-to-air vapor pressure deficits would trigger uncontrolled and sudden cavitation events. The combination of heat and drought stresses may therefore lead to an unsuspected risk of hydraulic failure. I explored this hypothesis with a new mechanistic model. The simulations support this hypothesis and highlight the critical role played by the cuticle phase transition temperature. Experiments are now awaited to confirm these predictions.

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Cochard, H.. 2019-02-03. A new mechanism for tree mortality due to drought and heatwaves. https://doi.org/10.1101/531632

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